Wednesday, December 19, 2012

The Fungal Meningitis Outbreak: Who's to Blame?

Whose fault was it that several batches of compounded drugs produced by a compounding pharmacy in Massachusetts led to hundreds of cases of fungal meningitis and 32 deaths in 19 states? Predictably, we’re now at the “blame-game” stage.  According to The Examiner, fingers are being pointed at the compounding pharmacy (for bad manufacturing practices); the Massachusetts state pharmacy board (responsible for oversight of the compounding pharmacy); poor communication between states; the FDA (for not fulfilling its mandate from Congress to “protect the public health”); even Congress itself (for enacting the laws under which the FDA operates).

Hopefully the various players will get beyond the blame game and come up with concrete solutions. This tragedy should be a wake-up call for regulators at all levels. We’ll be watching to see what (if anything) changes in the future.

Monday, December 10, 2012

Should Healthy People be Screened for HIV Infection?

According to the Centers for Disease Control (CDC), 25% of people who are infected with HIV do not know they are infected. Apparently these people are causing 80% of all new HIV infections. The available research suggests that if they knew they were infected they would make healthier choices in order to maintain their own health and protect the health of those they love. In the long run, that would reduce the rate of new HIV infections and ultimately lower our national health care costs.

At least that’s the logic behind the idea that all adults should routinely be tested for HIV infection. The American College of Physicians and Surgeons currently recommends that all persons older than 13 years should be tested. The CDC largely agrees, but adds that testing is not warranted in persons older than 64 or in populations with an HIV prevalence of less than 0.1%. However, the U.S. Preventive Services Task Force (USPSTF) does not yet recommend routine HIV screening of all persons; it recommends screening only patients “at increased risk”. As a result, routine screening for HIV infection is not yet commonplace.   It boils down to money; without a recommendation by the USPSTF, insurance companies are unlikely to pay for HIV tests in healthy people. 

Physicians groups and the CDC argue that patients don’t necessarily tell their physicians if they are at increased risk of HIV infection, so it’s nearly impossible to tell who is at increased risk. In addition, it’s hard for a physician to know the actual percentage of HIV in the patient’s population.

But now it appears that the USPSTF is considering changing its recommendation. The Task Force issued a draft document on Nov. 20 that, if approved, will recommend that all persons aged 15-65 be routinely screened for HIV infection. The draft document is available for public comment until Dec. 17.

Would routine screening for HIV infection be a good idea? You decide. You can comment on the USPSTF’s draft recommendation if you wish by going to to the USPSTF’s web page on the subject.

Thursday, December 6, 2012

Repetitive Mild Brain Injury and CTE

The evidence that there is a link between repetitive mild traumatic brain injury and a degenerative brain disease called chronic traumatic encephalopathy (CTE) continues to build. In the most recent study, published in the journal Brain, evidence of CTE was found in the brains of 68 of 85 subjects with a history of mild traumatic brain injury, including 34 of 35 NFL players and four out of five hockey players. In contrast, there was no evidence of CTE in the brains of 18 normal control subjects.

These new data should not be taken to mean that nearly all NFL players and hockey players are destined to develop CTE. It’s important to recognize that the subjects who were chosen for inclusion in the study were chosen specifically because they had been exposed to repetitive mild brain injury during their careers. Nevertheless, the numbers are pretty shocking. No one is suggesting that we give up sports such as football and hockey. But as the dangers of repetitive brain injury become more and more apparent, sports federations and professional sports leagues will need to look closely at how to protect athletes from these kinds of injuries.

Saturday, December 1, 2012

Oral Contraceptives Over-The-Counter?

A committee of the prestigious American College of Obstetrics and Gynecology (ACOG) issued a recommendation recently that oral contraceptives be made available over-the-counter (OTC). Currently, oral contraceptives are available only by prescription.

Some obstetricians and gynecologists benefit financially from the current prescription-only policy. Nevertheless, ACOG is advocating for OTC availability because it believes that the increased availability of oral contraceptives would go a long way toward reducing the high incidence of unwanted pregnancies in this country. The economic and social costs of unwanted pregnancies include costs for health care; costs associated with social welfare support for poor women and their infants; even the social costs of higher levels of domestic violence in families with unwanted children. According to ACOG, the added risks if oral contraceptives were available OTC would be minimal.

ACOG can only recommend, however. The FDA would have to approve the OTC sales of oral contraceptives, and so far, oral contraceptive manufacturers have not even applied for such approval. Perhaps with this recommendation they’ll be temped to do so.

Even if OTC sales of oral contraceptives are eventually approved, an age restriction could still apply, as it does for the “morning-after” pill (You must be 17 or older to purchase the morning-after pill over-the-counter.)

Friday, November 16, 2012

A Call for FDA Regulation of Compounding Pharmacies

As I predicted on this blog on Oct. 9, a recent outbreak of fungal meningitis has led to a renewed call for FDA regulatory authority over the burgeoning drug compounding industry. As you may recall, the outbreak was traced to bad batches of a steroid that had been packaged by a drug compounding company in Massachusetts. So far 461 people have been infected and 32 persons have died, according to the CDC.

Drug compounding used to be done by neighborhood pharmacies on a limited basis, primarily for local doctors and patients. Traditionally, pharmacies are regulated by the individual states. But with the rise of the Internet and of large health care systems and hospital chains, compounding pharmacies have become highly specialized, high-volume facilities that sell their products nationwide. And yet like all pharmacies, compounding facilities are still regulated primarily by the pharmacy boards of individual states.

This week the commissioner of the FDA appeared before a congressional committee to ask for increased authority to monitor and regulate compounding pharmacies. According to the commissioner, compounding pharmacies are not even required to give the FDA access to their books, for example. Surprisingly (or perhaps not so surprisingly!) the congressional committee seems to be split along party lines, with republicans arguing that the FDA already has enough authority to regulate compounding pharmacies and democrats arguing that the FDA should be given more regulatory authority. We’ll be watching this one.

Thursday, November 15, 2012

A Home Test for HIV

The first in-home HIV test kit became available last month in retail stores nationwide. The test kit, called OraQuick, was approved by the FDA in July, but it took until October to ramp up production and launch a nationwide sales effort.

The kit is designed to test a sample of oral fluid for antibodies to HIV in under 45 minutes. The kit has a reported false positive rate (identifying a person as HIV-infected when in fact he/she is not) of only 0.02%, or 1 in 5,000 persons. However, it has a false negative rate (failure to identify an HIV-infected person as infected) of 8%, meaning that HIV infection will be missed in 1 in 12 infected persons. The reason for the higher false negative rate is because the test detects the human antibodies that develop in response to HIV infection, not the HIV virus itself, and it takes several months after initial infection for these antibodies to develop.

A similar test has been available in doctors’ offices for some time. Nevertheless, health officials are hailing the home test as an important step forward in the fight against HIV-AIDS. The hope is that the availability of an inexpensive home test will encourage more people to test themselves for HIV infection, and then to seek treatment if they test positive.

Tuesday, November 13, 2012

Curing Mitochondrial-Based Genetic Diseases

As you may know, 37 of our roughly 22,000 genes are located within mitochondria, rather than in the nucleus. Consequently these 37 genes are inherited entirely from the mother, since the female provides the egg (with its haploid number of chromosomes) and all of the egg’s organelles including the mitochondria. The male provides a haploid number of nuclear chromosomes.

A few inherited diseases are due to defects in those 37 mitochondrial genes. In fact the chance is about 1 in 4,000 that a child will develop a mitochondrial-based disease. Researchers think that these diseases could be among the first heritable diseases that could be permanently cured, according to a news report in Nature. How? The potential mother (with the mitochondrial-based genetic disease) and a healthy female donor would each provide an egg. The nucleus of the potential mother’s egg would be removed and inserted into the healthy mother’s enucleated egg. The egg would be fertilized by the potential father’s sperm, allowed to develop into a zygote (an early stage of development), and then inserted into the potential mother for development.

The child would have genes from two women, of course, but not very many from the donor woman - only 37 out of 22,000. And the child and all of its future descendants would be forever free of the disease.

So far, this has not yet been attempted beyond the zygote development stage. For one, genetically engineering a child is currently illegal. For another, the researchers who carried out the experiment to the zygote stage found a disturbing number of abnormalities in the zygotes they created. The researchers believe, however, that with further experimentation these problems could be overcome. The fact that we’re so close to curing a whole class of heritable diseases is likely to stimulate debate over whether such experiments should ever be conducted.

Sunday, November 4, 2012

Austalopithecus afarensis Definitely Climbed Trees

Analysis of the partial skeleton of “Lucy”, the best-known skeleton of Australopithecus afarensis discovered in 1974, revealed that the species was capable of standing and walking upright.  Many scientists presumed, based on the probable shape of her shoulder bones (some bones were missing) that she also still climbed trees, like her ancestors.  Others disagreed, arguing that the shape of her shoulder was just a vestigial retention from her ancestry, no longer of any real functional value.

To resolve this issue, researchers compared the anatomy of the scapula bone of a partial skeleton of a recently-discovered juvenile A. afarensis to the growth patterns of scapula bones of humans and modern apes.  They concluded that A. afarensis, like modern apes, used its upper limbs to climb and move through trees, at least part of the time.  Perhaps they slept in trees as a protective strategy, or climbed trees to harvest food.

The unique shoulder anatomy that permits overhead use of the upper limbs to climb and swing from trees disappeared in Homo erectus, a later transitional species in the human lineage.

Friday, November 2, 2012

Pregnancy Complications Among Women Born Pre-term

Women who were born pre-term are more likely to have pregnancy-related complications during their own pregnancies, according to Canadian researchers.

The authors compared pregnancy complications in over 7,000 women who were born pre-term, to nearly 17,000 women born at full term.  Women who were born before 36 weeks of gestation were 14% more likely to suffer gestational diabetes, gestational hypertension, or preeclampsia during their own pregnancies than women who were born full-term.   Women born before 32 weeks almost twice as likely to suffer these complications.

Fortunately, none of these pregnancy-related complications is terribly common.  In addition, all are tested for during normal prenatal care, and all can generally be managed when detected.  Women who were born pre-term should not be overly concerned, though they may wish to alert their pre-natal caregiver to ensure that follow-up is adequate.

Monday, October 29, 2012

The Benefits of Quitting Smoking

Are you a smoker? Are you one of those who believe that smoking may not be as dangerous as “they” say it is?

Well, thirty years ago you’d have had a point.  It’s actually taken a long time to collect sufficient data to prove that smoking is as harmful as it is.  That’s because smoking-related diseases can take decades to develop.  Only after an entire generation of smokers reaches old age can we truly know the health-and-survival differences between smokers and non-smokers.  But the data are now becoming available, and its pretty convincing.  A 12-year-long British study of 1.2 million women born between 1938 and 1945 shows that women who smoked throughout their lives shortened their lives on average by more than ten years.  Ten years!  (The study was conducted in women born between 1938 and 1945 because smoking only became popular among women in the 1950s, when these women were entering their teens.)

Now for the good news.  Smokers who quit markedly reduced their risk of smoking-related diseases and a shortened lifespan.  How much their risk was reduced depended on the age at which they quit. For example, women who quit by age 40 lowered their smoking-related risk of death by 90%. Women who quit by age 30 lowered their risk by a whopping 97%.

What this means is that if you quit while you are still young, you can still live a long and normal life. Is that enough incentive for you to quit?

Saturday, October 27, 2012

Health Concerns Over Energy Drinks

The death of five teenagers since 2009 following the consumption of high-energy drinks has renewed calls for the FDA to do something about regulating these products. At the moment, the makers of energy drinks are not required to disclose how much caffeine their products contain, because they are marketed as beverages or dietary supplements, not drugs. But as the sales of such products have soared (doubling since 2006), so too have emergency room visits linked to energy drinks –over 13,000 in 2009 (the last year for which data are available), according to the federal Substance Abuse and Mental Health Services Administration.

Canada is ahead of the game when it comes to regulation of energy drinks, compared to the U.S. Under new Canadian rules, energy drinks will be limited to 180 mg of caffeine per can. That’s less than is in some of the most popular energy drinks, such as the 24-oz. can of Monster Energy and the 20-oz Red Bull. The American Beverage Association, which represents some of the energy drink companies in the U.S., has said it will resist the establishment of caffeine limits in the U.S.

How much caffeine can be packed into commercially-available caffeine products? A 3-tablespoon squeeze bottle of MiO liquid “water enhancer”, sold by Kraft Foods, contains over 1,000 mg of caffeine – roughly equivalent to 8-10 cups of coffee.

For more on this subject, go to a previous blog post titled "Alcohol and Caffeine - A Potent Mix."

Sunday, October 21, 2012

The HPV Vaccine and Sexual Activity

The vaccine against the HPV virus responsible for most cases of cervical cancer has been somewhat controversial ever since it first came out in 2006. The vaccine, called Gardasil, needs to be given before the onset of sexual activity to be completely effective because the HPV virus is sexually transmitted.  Generally the recommendation has been that it be given to girls at about age 11 or 12.

And that’s what has fueled the controversy; some parents have objected to the virus being given to girls that young because they believe it may encourage sexual activity at an age when it really isn’t appropriate.  As a result, many girls have not been vaccinated against the virus when they should be.  Are the parental concerns justified?

Shortly after the vaccine became available, several studies reported that administration of the vaccine did not seem to encourage sexual activity.  However, the early studies were based solely on sexual activity surveys, admittedly not the best way to collect accurate data.  Now a new study published in the journal Pediatrics confirms the earlier studies with data that are independent of self-reports.  The authors of the study examined the medical records of nearly 1,400 girls aged 11 through 12 for up to three years, looking for indirect evidence of sexual activity such as pregnancy, sexually transmitted infection, or contraceptive counseling.  The authors found no evidence of increases in any of these measures in girls given the vaccine at age 11 or 12, versus girls of the same age not given the vaccine.  So at least by these measures, there is no evidence that girls given Gardasil are more likely to engage in sexual activity at an early age.

Hopefully this will relieve some parents and encourage them to have their girls vaccinated.  Currently only about half of all 13- to 17-year-old girls have been vaccinated against HPV; far less than have been vaccinated against non-sexually transmitted diseases such as tetanus and diphtheria, and whooping cough.

Sunday, October 14, 2012

Journalistic Bias in Science Reporting

How good are newspapers at reporting on follow-up scientific studies on a particular subject, as opposed to focusing only on the initial high-profile hypothesis?

To find out, a team of scientists from France and the U.S. identified the top ten most cited scientific articles published in the 1990s on Attention Deficit Hyperactivity Disorder (ADHD). Then they examined the follow-up scientific articles related to each of the ten articles to try to ascertain whether the initial hypotheses in those ten articles had actually stood up to subsequent scientific evaluation. Lastly, they looked at newspaper coverage of both the top ten articles and the follow-up articles. According to the team of scientists, only two of the top ten most cited articles on ADHD were subsequently fully confirmed by other scientific articles. The other eight were either refuted, “strongly attenuated”, or considered unlikely by subsequent scientific articles. This is exactly how good science works; through a continuous process of tests, hypothesis modification, and retests, we come ever closer to the truth, and its not always what it seems at the beginning.

Newspaper coverage of ADHD, however, showed a distinct bias toward the sensational new hypothesis or initial findings, regardless of whether the hypothesis or the findings later proved to be true or not. There were 223 newspaper articles covering the hypotheses and initial findings of the top 10 scientific studies on ADHD in the 1990s. In contrast, there were only 57 newspaper articles covering all 67 scientific follow-up studies, and only one of those newspaper articles reported that a “top 10” paper was being “attenuated” by the newer scientific study’s findings.

No wonder the public is confused. They learn something from the public media one day, and never learn later that our knowledge about the subject has changed through good scientific investigation. Or as the study’s authors put it, “Because newspapers failed to inform the lay public that most initial scientific claims were later refuted or strongly attenuated, they did not reflect the evolution of scientific knowledge."

Saturday, October 13, 2012

Arctic Sea Ice Continues to Melt

2012 was another record year for the lowest amount of sea ice in the arctic during the summer, according to the National Snow and Ice Data Center (NSIDC). At its lowest point in September, sea ice covered only 3.61 million square kilometers of the Arctic Ocean. The arctic ice has been declining steadily for several decades now; coverage is currently less than half of what it was in the 1980s. If this keeps up, within several decades the arctic ice could come close to disappearing every summer. That can’t be good for polar bears…

Climatologists believe that the decline is a due global warming. Warmer air melts more ice, of course. But scientists postulate that the rapid melting is also due to warmer waters from the North Atlantic that are entering the region. In addition, warm air picks up more moisture, leading to clouds that trap even more warm air below them.

Interestingly, the ice cover over Antarctica (at the south pole) has actually increased slightly since the 1980s, according to the NSIDC. Climatologists explain this, too, as due to global warming. Specifically, as the Pacific Ocean warms up it delivers more moisture to the strong winds that blow in a circular pattern around the perennially cold Antarctic, and this leads to a greater snowfall over the Antarctic.

We’re just beginning to see the many and varied effects of global warming.

Tuesday, October 9, 2012

Drug Compounding Pharmacies

In the past few weeks, 119 people have come down with a rare condition called fungal meningitis (a fungal infection of the meninges of the central nervous system), according to the CDC. Eleven people have died. An investigation into the rapidly rising number of cases of the condition (which, by the way, is not contagious) quickly focused on a batch of steroid drugs that had been prepared at a Massachusetts-based drug compounding pharmacy.

Drug compounding pharmacies provide an important service to the health care industry. Drug compounding pharmacies don’t actually make drugs; they buy FDA-regulated drugs in bulk from the drug’s manufacturer and then repackage or reformulate them according to the needs of their customers. Perhaps the customer (such as a major hospital or a chain of medical clinics) requests a specific dose of a drug in a specific-sized vial, or wants several different drugs combined in a single vial or pill. Drug compounding pharmacies prepare the vials or pills accordingly.  In the current case, the compounding pharmacy was preparing vials of steroids in a liquid form for injection into patients’ spinal cords, for the control of pain.  Apparently some of the vials of steroid became infected with an unknown fungus.

Because drug compounding pharmacies don’t actually make the drugs, they are not subject to the same oversight by the FDA as are the drugs’ manufacturers. Instead, like all pharmacies, they are regulated by state laws. Perhaps this recent outbreak of meningitis will lead to a review of how the industry is regulated and inspected by the various states, because here’s a case where a mistake at a compounding pharmacy in one state has apparently lead to cases of fungal meningitis in 10 states at last count, and deaths in four. We need to have confidence that our drugs (and their various formulations) are safe when they cross state lines.

Tuesday, October 2, 2012

Knee and Hip Replacement Surgeries are on the Rise

The surgical techniques required for successful replacement of knee and hip joints (knee and hip arthroplasties) were first developed in the 1950s and ‘60s. The mechanical devices used to replace damaged knees and hips became commercially available in the 1970s. Today, over a million total hip and knee replacements are performed in the United States every year, according to the National Hospital Discharge Survey of the CDC. There’s even a specialist group of surgeons who focus primarily on these two surgeries (the American Association of Knee and Hip Surgeons).

Why are these two surgeries becoming so commonplace? For one, the surgeries are highly successful at eliminating the pain associated with hip and knee osteoarthritis. They’re also fairly low-risk. People are living longer and want to maintain their mobility as long as possible. And last but probably not least, the rate of obesity continues to rise in this country. Obesity places an extra burden on knee and hip joints, increasing the risk of the development of knee and hip osteoarthritis.

The number of knee and hip arthroplasties is expected to top 4 million per year by 2030. The American Association of Knee and Hip Surgeons is going to need a lot of new members by then….

Friday, September 28, 2012

A Water Desalination Plant for San Diego

Only 1% of Earth’s water is fresh water; 97% is saltwater and the remaining 2% is frozen in glaciers. Worse yet, water is not evenly distributed around the world. Growing cities frequently have problems getting enough fresh water to supply their needs.

The city of San Diego, after years of dealing with water shortages and expensive water sources, has decided to take matters into its own hands. The city signed a deal this week to purchase all of the output of what will be the largest desalination plant in the Western hemisphere, if/when it is completed in 2016. The new plant, to be located in Carlsbad, California, is expected to produce 50 million gallons of freshwater a day

Desalination of seawater may seem like a good idea, but it has yet to catch on in a big way. For one, desalination uses a lot of electricity, and thus is still fairly expensive compared to most natural sources of water. In addition, by removing the salt from seawater and returning it to the sea, desalination plants can raise the local seawater salinity, affecting sea life if the salt is not sufficiently disbursed.

The Carlsbad desalination plant is likely to be watched with interest by officials from other coastal cities with water shortages. Either it will prove to be a one-of-a-kind project that didn’t go quite as well as planned, or it will lead the way to the development of other desalination plants for supplying water to other thirsty coastal cities.

Wednesday, September 26, 2012

BPA and Childhood Obesity

Last week a scientific article in the Journal of the American Medical Association indicated that there is an association between childhood obesity and bisphenol A (BPA), a plastic used to coat the inside of food cans. The authors of the report measured the concentrations of BPA in urine (a rough measure of BPA exposure) in over 2,800 children. They found that the most obese quartile of the children also had the highest levels of urinary BPA. The authors were quick to point out (correctly) that the observed association between obesity and high concentrations of BPA does not prove that BPA causes obesity. Although the findings are certainly intriguing, there are other possible explanations. For example, perhaps the obese children were obese because they ate more food (ingested more calories) from containers lined with BPA, so that their high BPA levels are just a consequence of where they got their calories. Or perhaps obese children store more BPA in their fat. Incidentally, the authors based their findings on data obtained from questionnaires, a notoriously poor way to obtain accurate information about dietary intake.

In science, words matter.  The headlines of most popular press news coverage of the JAMA article correctly used phrases like “an association” or “a link” to describe the relationship between obesity and BPA. Others were not so careful; the headline in the International Business Times was “BPA Causes Obesity in Children, New Study Shows”.

Unfortunately, such sloppy (or agenda-driven) reporting of science news only scares and confuses consumers. The American Chemistry Society, admittedly a group that itself might have an agenda, felt obligated to issue a press release on BPA this week, pointing out that the study’s authors themselves stated “…causation cannot be inferred from a cross-sectional association…”.

I’m not trying to defend BPA; frankly I think the jury is still out concerning its risk to human health. In the face of uncertainty, though, there’s nothing wrong with deciding to err on the side of caution and cutting down on the use of BPA in food containers, especially if suitable substitutes can be found. For example, BPA has already been removed from babies’ bottles. But the American Chemisty Society is right; the evidence presented in the most recent study does not prove that BPA causes or even contributes to childhood obesity. This time, the International Business Times just plain got it wrong.

Tuesday, September 18, 2012

Ultrasound Enhances Transdermal Drug Delivery

Most medical drugs are administered as an injection or are taken orally as pills or liquids.  Both drug delivery methods have their drawbacks; injection requires at least some technical expertise and the availability of sterile syringes and needles and also involves some pain.   Oral ingestion is not very effective for proteins and other macromolecules that are easily degraded by the digestive system.

The idea that ultrasound could be used to enhance the delivery of drugs directly across the skin (transdermal delivery) has been around for many years.  Progress was slow until about two decades ago, when it was discovered that low-frequency sound waves (20-100 kHz) were more effective than the higher frequencies (700 kHz and above) being used at the time.  If you’re interested, see the review on this subject published in 2010.

A potential breakthrough in the field came this month when the same authors who wrote the 2010 review published new data showing that using both low- and high-frequency ultrasound together caused better drug absorption across the skin than using either frequency alone.   A proposed mechanism for the enhancement is described in the paper, reviewed this week by ScienceDaily.

A lot of work still needs to be done (including safety and effectiveness studies and finally FDA approval) before ultrasound-enhanced drug delivery becomes commonplace.  But its likely that in your lifetime, you’ll be prescribed a therapeutic drug in a cream or ointment form and given a small hand-held ultrasound device to enhance its absorption through the skin.

Sunday, September 9, 2012

First Drug Approved for HIV Prevention

For the first time, the U.S. Food and Drug Administration (FDA) has approved a drug specifically for the prevention of sexually-acquired HIV infection. The drug, called Truvada, is currently being used in combination with other drugs in the treatment of existing HIV infections.

Not everyone is happy about the FDA’s decision. The main concern is that using the drug in a large number of uninfected individuals could increase the risk of the HIV virus becoming resistant to the drug. To reduce that possibility, the FDA is asking health professionals to prescribe the drug only to high at-risk individuals (such as partners of HIV-infected persons) who have been tested for HIV and are currently negative. In addition, individuals who are taking the drug should be retested every three months to ensure that they remain negative, because Truvada alone is not recommended for HIV-infected individuals. But retesting for HIV status every three months is asking a lot in terms of compliance by health professionals and patients.

Health officials will be watching closely for any signs of the development of resistance of the HIV virus to Truvada. Whether or not patients on Truvada actually comply with the HIV re-testing recommendation will be of interest, too.

Thursday, September 6, 2012

Organic Foods Are Not More Nutritious

If you’ve watched a newscast this week you can hardly have missed it.  News flash!  Organic foods are no more nutritious than conventional foods.  There seemed to be a self-righteous tone to some of these reports, as if the “discovery” proved something important (or gave the reporter a justification for NOT choosing organic foods him/herself :).

In the study highlighted in the news this week, researchers at Stanford University reviewed and summarized virtually all the data available from 223 previous studies in which the nutritional value of organic and conventional foods were compared.  Taken together, the studies showed no significant difference in nutritional value between organic and conventional foods.  And in the very few studies in which the health effects of eating organic foods were assessed, there were no obvious health benefits, either.  In essence, this is not "new" news, but a rehash of old news.

And so what?  People who choose organic foods don’t necessarily choose them because they think they are more nutritious.  The primary concern of most organic food buyers is a belief that the ingestion of pesticides and herbicides is harmful, especially to pregnant women and young children.  And yes, the researchers DID find that organic foods had fewer (and lower) pesticide residues than conventional foods.   (Most news reports were quick to point out that the levels of pesticides in conventional foods were within acceptable limits according to current regulations).  By the way, where organic foods get their pesticide residues is not clear; contamination of equipment used to harvest or transport organic foods, blow-by of spray from nearby non-organic farms, even cheating by organic farmers are all possibilities.

Some people choose organic foods out of concern for the environmental impact of excessive use of pesticides and other chemicals, such as antibiotics.   Others think they may taste better; still others wish to support smaller local organic farmers.  These are certainly valid reasons. So choose organic foods if you wish and if you can afford them – just don’t do it because you believe they are more nutritious.

Monday, September 3, 2012

Caloric Restriction and Longevity, Revisited

Does severe caloric restriction really lead to longer life? Back in 2009, a research study from the University of Wisconsin (performed with primates) suggested that it does. But now a second study, also in primates, seems to contradict that finding. The latest study, from the respected National Institute on Aging, began 25 years ago and is still ongoing. But the data so far show no positive effect of caloric restriction on longevity. These findings are corroborated by experiments in 41 different strains of mice that showed that caloric restriction has little or no effect on life span overall – it increased length of life in some strains, had no effect in others, and actually reduced lifespan in some strains.

Why the contradictions? No one is sure, but certainly there were differences in how the two primate studies were done. The initial study omitted some primates from inclusion in the final statistics, arguing that they did not die from “age-related” causes. There were differences in diets used as well.

It’s still possible that caloric restriction does lead to some health benefits other than simply length of life. Indeed, in the most recent primate study, caloric restriction did seem to lower cholesterol and sugar levels in some of the monkeys. But the current data are not particularly encouraging when it comes to the efficacy of caloric restriction in extending life span.

For more on this subject, go to a previous blog post titled "Caloric Restriction and Longevity."

Wednesday, August 29, 2012

Bone Density Scans are Over-Recommended in Younger Patients

The American Academy of Family Physicians currently recommends that its members not do bone density scans (dual-emission X-ray absorptiometry - DEXA) to test for bone loss in healthy women who are under the age of 65; for men the age is 70. And yet, many family practice physicians and internists are doing the scans on their younger patients anyway.

The reasons for the disconnect are complex. Many physicians own the X-ray machines used to do bone density scans and therefore they have a financial incentive to recommend a scan. Others simply may not know of the latest recommendations or are taking a defensive medicine approach – the more tests, the better. But it’s not always the physician’s fault; sometimes the patient is aware of the dangers of osteoporosis and asks to be tested, without knowing whether the test is really appropriate for his/her situation.

Knowing when to use medical tests (and when not to) is not always easy. At the very least, it requires a knowledgeable physician and good communication between doctor and patient.

On the flip side, there are indications that bone density scans are being under-utilized in older patients; the ones who actually need them. In recent years there has been a decline in bone density scans under Medicare due to cuts in Medicare Part B reimbursements.

Monday, August 27, 2012

Older Fathers Pass On More Mutations

A recent study shows that men pass on more random mutations to their offspring than do women – about four times more, in fact. In addition, the number of mutations rises with the man’s age, approximately doubling from age 20 to age 40. In contrast, the number of mutations women pass on to their offspring is essentially unaffected by maternal age.

Actually, this makes sense. Women typically are born with all the eggs they’ll ever have, so there’s essentially no chance for the eggs to undergo genetic change throughout her life. In men, the cells that eventually lead to sperm continue to divide throughout a man’s life. As these cells divide they may accumulate mutations that are passed on.

The observation fits with a previous observation, published in April in Nature, that older men are more likely to have a mutation in a specific gene linked to autism and to father children with autism.

Wednesday, August 22, 2012

Human Genes ARE Patentable (At Least for Now)

In yet another installment of the long-standing battle, over whether human genes are patentable, the U.S Court of Appeals for the Federal Circuit has affirmed its earlier ruling that human genes ARE patentable once they are isolated and sequenced. But first they had to get past a Supreme Court ruling that “products of nature” cannot be patented.

A company called Myriad Genetics believed that it held valid patents on two important gene variants; the BRCA1 and BRCA2 genes that confer an especially high risk of breast cancer in women. Myriad Genetics argued successfully this time around that once a gene has been isolated and sequenced, it is in a form that never appears in nature! Technically, they are right; in nature a gene is always associated with histone proteins and is always part of a much larger DNA sequence that constitutes a chromosome. An isolated and fully sequenced gene, according to Myriad Genetics, is a chemically altered structure produced by man, and hence is patentable. The Court of Appeals agreed. An analogy would be that a baseball bat (a form invented by man) is patentable, but a tree trunk (a “product of nature”) is not.

Not everyone likes the ruling, for it appears to stand on a technicality; that “in nature” genes are associated with histone proteins. Everyone knows that it’s knowing and controlling the nucleotide sequence of genes that’s going to be important commercially – not the presence or absence the histones. But for now the ruling stands, and Myriad Genetics can continue to control the market for BRCA1 and BRCA2 gene test kits. And that’s the point of patents, isn’t it? Patents provide the incentive for companies to spend money developing important new technologies, such as tests for a high-risk genes.

Thursday, August 16, 2012

Semenya Takes the Silver Medal

After a slow start that had her running dead last at the 200-meter mark, Caster Semenya turned on the afterburners and blew past six other runners, placing second and earning the silver medal in the 800-meter event at the summer Olympic Games in London this month.

Ms. Semenya, as you may recall, was the young woman whose gender was questioned after winning the 800-meter event at the world championships in 2009. After her win she was hustled out of the stadium before she could even finish her victory lap. She was out of competition for nearly a year while the International Association of Athletics Federations (IAAF), international track and field’s governing body, “decided” whether she could compete as a woman. Ultimately the IAAF decided that she could compete, but the incident caused enormous embarrassment to the 18-year-old Semenya; embarrassment that could have been avoided if the IAAF had had a gender decision policy in place and made its gender determination before the event, not after.

Following her second-place finish at the Olympic Games, there have been rumors that Ms. Semenya might have deliberately held back, taking second place to avoid re-igniting a controversy had she won the gold. Really? If you had survived an embarrassment like Ms. Semenya’s and then trained hard for two years for the Olympic Games, would you be able to deliberately not go for the gold? Somehow I doubt it.

Ms. Semenya’s gender didn’t become an issue at these past Olympic Games. The Olympic Committee planned to rely on a test of testosterone levels, but said they would only test female athletes if the athlete’s performance was questioned. Neither the IAAF nor the Olympic Committee has a policy of screening all female athletes equally beforehand, in order to avoid publicly embarrassing athletes who ultimately are not allowed to compete as women.

Monday, August 13, 2012

Obesity and Kidney Donation

Over 90,000 patients with advanced renal failure are waiting for a suitable kidney for a transplant. There are simply too few cadaveric kidneys available, and not enough suitable living donors, either.

Live donor kidney donation is considered safe for persons who are in good health. Long-term follow-up studies of persons who donated kidneys as long as 50 years ago have shown past donors live just as long as one would expect. To ensure that donors are not put at risk, potential kidney donors are screened for good health before they are allowed to donate.

Persons who are obese may be rejected as potential kidney donors even though they are otherwise in good health. That’s because obesity is a known risk factor for kidney disease later in life. There are no hard-and-fast weight limits to be allowed to donate a kidney because no one knows whether donating a kidney would actually increase an obese person’s chances of kidney disease later in life. Nevertheless, many kidney transplant centers aren’t willing to take the risk. More than half of all kidney transplant centers set a Body Mass Index (BMI) of 35 as an upper limit for an acceptable donor; 10% set the limit even lower, at a BMI of 30.

According to a presentation at a recent clinical meeting of the National Kidney Foundation, one transplant center found that 37% of its potential living kidney donors were obese (BMI>30) and another 22% were morbidly obese (BMI>35). Although the morbidly obese potential donors received nutritional counseling and follow-up, fewer than 15% lost enough weight and eventually were allowed to donate a kidney.

Obesity is on the rise in this country. It’s a shame that the potential pool of living kidney donors, never large enough to begin with, may shrink even further with the rise in obesity.

Sunday, August 5, 2012

Texting While Driving –“Don’t Do It”

While driving home from college last January, Texas student Chance Bothe texted a friend, “I need to quit texting because I could die in a car accident and then how would you feel… ”.   His last text was “b right there”, according to KHOU11 News in Houston.  Moments later he drove off a bridge and into a ravine.  He suffered brain injuries, a broken neck, broken facial bones, a punctured lung, and too many bones to count.

Young Mr. Bothe was released from the hospital last week after six months of reconstructive surgery and all kinds of therapy, including speech therapy to learn to talk and physical therapy to regain his ability to walk.   He still has a long road of recovery in front of him, but he’s recovered enough to want to send a message to others.   He says about texting while driving, “Don’t do it. It’s not worth losing your life.”

Mr. Bothe’s tragic story is just one of a litany of such stories since texting became common.  Laws restricting texting while driving are either on the books or are being considered in most of the 50 states. And for good reason.

Wednesday, August 1, 2012

Cancer Treatment Can Sometimes Cause Cancer

The two primary treatment methodologies for cancers – radiation and chemotherapy – are about as subtle as a sledgehammer. The goal of both treatments is to damage and thus to wipe out the rapidly-dividing cancer cells, but in the process they may also damage or kill normal cells undergoing growth and division. That’s why cancer patients lose their hair and feel nauseous after treatment; the treatments have damaged the cells of hair follicles and the cells that line the digestive tract.

It’s now known that sometimes chemotherapy and radiation can lead to additional cancers that are caused by the treatments themselves. That’s apparently what happened to Robin Roberts, the anchor of the “Good Morning America” show. Ms. Roberts received radiation and chemotherapy treatment in 2007 as part of her treatment for breast cancer. Now she’s been diagnosed with myelodysplastic syndrome (MDS), a potentially fatal blood and bone marrow disease that used to be called proleukemia.

Ms. Roberts’ MDS is called a secondary cancer – either a new, different primary cancer that comes after a diagnosis of primary cancer, or (more commonly) a cancer that has spread from its primary site to other parts of the body. Ms. Roberts’ MDS is of the first type. Although it could have been just an unlucky unrelated event, statistically its much more likely to have been caused by her prior cancer treatment.

No doubt about it, chemotherapy and radiation therapy are hard on the body. But they’re getting better every year. Researchers are finding better ways to target cancer cells specifically, thereby sparing normal cells the damage that comes with traditional cancer therapy. Hopefully, that will reduce the number of secondary cancers caused by cancer therapy itself, like Ms’ Roberts’ MDS.

Ms. Roberts plans to have a bone marrow transplant sometime within the next two months. Her sister is likely to be the bone marrow donor, according to news reports.

Saturday, July 28, 2012

HCG Diet Products Are Still Available

In March of last year I blogged about a diet fad in which dieters are urged to restrict themselves to 500 calories per day and take shots of human chorionic gonadotropin (HCG), a hormone.

The Food and Drug Administration (FDA) takes a firm stand against HCG diet products, calling them unapproved, illegal and potentially dangerous. The agency has even sent warning letters to manufacturers and distributors of HCG products, warning them that they are selling illegal homeopathic drugs.

Nevertheless, on an interstate highway near where I live there’s a billboard promoting a local clinic that provides these products for weight loss! Technically, it’s legal. HCG is approved for at least one medical condition (female infertility), so physicians can order it and prescribe it. The drug laws in the U.S. allow a doctor to decide what is best for his/her patient regardless of whether or not a drug is actually approved for a particular use. So the FDA can’t stop the clinics from using HCG products as diet drugs; it can only try to strong-arm manufacturers and distributors.

The bottom line is that HCG is widely available for dieters, even though it is not approved for dieting for the FDA. Google “HCG diet” and you’ll find clinics willing to sell this snake oil, right along with news and medical sites saying it doesn’t work.

Tuesday, July 24, 2012

Bisphenol-A Banned From Plastic Babies’ Bottles

The Food and Drug Administration (FDA) has finally banned bisphenol-A (BPA) as an ingredient in plastic babies’ bottles and sippy cups, according to an Associated Press report of July 17, 2012.

Well, good for them. But in fact the FDA took action only after the agency was asked to do so by the American Chemistry Council, a chemical industry trade group. It turns out that plastics manufacturers had already voluntarily removed BPA from babies’s bottles and sippy cups. The American Chemistry Council had asked the FDA to ban BPA from these products largely to improve the public image of the industry and these products.

The FDA has argued for some time now that that the currently available scientific evidence does not support the conclusion that the amounts of BPA ingested by adults are unsafe. Nevertheless, the agency continues to review the evidence regarding to the safety of BPA in food packaging, and is likely to take action if and when it is warranted.

Saturday, July 7, 2012

New Pop Warner Safety Rules for Football Practice

Recent evidence suggests that repetitive sub-concussive blows to the head may contribute to the development of permanent brain damage later in life. In response to this evidence, Pop Warner announced last month that it is instituting new rules governing football practice sessions. Pop Warner is the oldest and largest youth football, cheer, and dance organization association in the world, with over 400,00 participants between the ages of 5 and 16.

Under the new rules, only a third of practice time can be devoted to contact drills, nor can contact drills exceed 40 minutes per practice session. Full-speed head-on tackling drills are banned. Head-on tackling drills are only allowed if the players line up less than three yards apart. Full-speed contact during drills is still allowed, but it must be at an angle, not straight on. There should be no intentional head-to-head contact, ever.

The organization is clearly taking the lead on safety. No other football organization at any level has such strict rules governing practice. The organization knows that the aggressive culture of football may make acceptance of the new rules a hard sell among some coaches, but believes that the new rules are important for the safety of the players and even the very survival of the game. The new rules will be in effect during the 2012 season.

It’ll be interesting to see how high school, college, and even pro football organizations respond to the current concerns about head injuries in football. Can we make the sport safe enough, if not completely safe?

Thursday, July 5, 2012

Global Warming Self-Perpetuating Events

One of the concerns about global warming is that there may be a “tipping point” temperature at which global warming could become more rapid and potentially unstoppable by human intervention. To date, a tipping point for global warming as a whole has not been identified. But at least two events linked to global warming do seem to have the potential to be self-perpetuating, triggering even further global warming.

One such self-perpetuating event is the thawing of glaciers, most notably in Greenland. Melting glaciers leave behind are newly exposed areas of land, sea, or dark melt-water pools, all three of which absorb more light energy than snow or ice. This causes more local warming, which in turn causes more melting, which then causes more warming, more melting, and so on. It’s like a positive feedback event, with no obvious end in sight.

Another potential self-sustaining warming event is thawing of the permafrost (land that is generally frozen all the time) at northernmost latitudes. The concern is that thawed permafrost will release large amounts of carbon dioxide and methane currently trapped in the frozen earth. Since both carbon dioxide and methane are greenhouse gases, this will further exacerbate global warming, leading to more thawing of permafrost, then more carbon dioxide and methane released…..

Will global warming as a whole become self-perpetuating? Right now, no one knows. Perhaps the best policy would be to try to control global carbon dioxide emissions soon so that if there is a tipping point temperature, we don’t exceed it.

Sunday, July 1, 2012

Gender Determination at the 2012 Olympic Games

With the 2012 summer Olympic games less than four weeks away, it’s worth asking: How will the International Olympics Committee (IOC) determine the gender of an athlete, if his/her gender is called into question?   You may recall the embarrassing incident suffered by Caster Semenya back in 2009 when she won the 800-meter event at an international track and field event (this blog Sept. 7, 2009).  It took another 10 months for a committee to decide she could compete as a woman (this blog July 7, 2010).  The delay and uncertainty were embarrassments for Ms. Semenya and for the international track and field governing body.

Here’s the IOC has tried in the past and what they’ll be doing this year in London:

1) The “nude parade”.  In the 1960 and 1964 games, female athletes were required to walk nude in front of a physician.   Aside from the obvious invasion of privacy issue, some people are born with both male and female genitalia, making the policy essentially ineffective.

2) Chromosome analysis.  By 1968 the IOC was using chromosome analysis to establish sex – XX for female and XY for male.  But some males have an extra X chromosome, and some females are missing the X. Should they be allowed to compete?

3) Hormone tests.  This year the IOC proposes to use testosterone levels to determine gender.  Males generally have much higher testosterone levels, of course, but in there can be a fairly wide range of testosterone levels in both genders.   Can the IOC be absolutely certain that there is no natural overlap, ever, in testosterone levels between males and females?

It’ll be interesting to see if any gender controversies arise in London this year.

Saturday, June 30, 2012

Antibiotic-Resistant Gonorrhea On the Rise

Last year I reported on this blog that there were signs that gonorrhea was becoming resistant to all known classes of antibiotics (this blog, July 14, 2011). This month the World Health Organization (WHO) reported that cases of the antibiotic-resistant gonorrhea have shown up in six countries – Norway, Sweden, Britain, France, Japan, and Australia.

The WHO is calling for more research into new treatment options. It also plans to monitor the use of antibiotics in an effort to encourage their correct use.

Gonorrhea used to be treatable with all known classes of antibiotics. It’s on its way to becoming virtually untreatable, or at least very difficult to treat. And that would be a problem for the more than 100 million people who become infected with the gonorrhea each year.

Monday, June 25, 2012

Mother Challenges Law Prohibiting Organ Sales

Thirteen years ago Doreen Flynn gave birth to a daughter with Fanconi anemia, a rare inherited blood disorder in which the bone marrow does not make enough red blood cells. Six years later Ms. Flynn underwent an in vitro fertilization (IVF) procedure and had two more daughters in the hope that one of them would be a suitable donor for her older daughter. But in an ironic twist of fate, embryonic screening failed to detect that they, too, would suffer from the disease. Now she has three daughters with the disease, instead of just one.

All three children will need bone marrow stem cells from an unrelated donor in order to survive. They could wait for a match to potential donors currently registered with the National Bone Marrow Donor Program, but there’s a problem; almost half of all potential donors fail to complete the donation procedure when they are matched to a recipient, leaving the recipient without the treatment he/she so desperately needs.

The National Organ Transplant Act of 1984 made it illegal to buy or sell "organs or organ parts".  Under the old rules that included bone marrow. Ms. Flynn wanted to see that change, so she became the lead plaintiff in a lawsuit that challenged the prohibition against selling bone marrow stem cells. The main argument in the lawsuit was that bone marrow, unlike a kidney or a lung, regenerates in a matter of weeks. Further strengthening the argument is the fact that the technology for collecting stem cells from bone marrow has changed since the National Organ Transplant Act was written. Instead of collecting the donor’s bone marrow by a needle inserted into the hip bone, donors now receive a drug to stimulate the production of the precursor cells. A machine then separates the precursor cells from whole blood by a technique called peripheral apheresis. In effect, Ms. Flynn's lawsuit argued that bone marrow stem cells should now considered more like body fluids such as blood plasma or sperm (which you can sell) than an organ such as a kidney or heart (which you cannot).

In December of 2011 the U.S. Court of Appeals for the 9th Circuit  ruled in favor of Ms. Flynn.  Bone marrow stem cells can now be sold, but only if they are collected from the bloodstream by apheresis, not from bone.  The court also stipulated that any payment would need to be in the form of scholarship vouchers or donations to charity.

It appears the new ruling will stand, because the U.S. Attorney General has decided not to ask the U.S. Supreme Court to review the case.

Friday, June 22, 2012

Bird Flu Papers Finally Published

After months of delay, two controversial papers about the bird flu virus have finally been published. The papers appear in May 2 issue of Nature and in the June 22 issue of Science.

Publication of both papers was held up because of the potentially dangerous nature of the information they contained; both papers documented methods that increased the airborne transmissibility of the bird flu virus in species other than birds. Although the current virus is highly contagious and deadly in birds and deadly to humans in the rare cases when humans have become infected, so far the virus has not shown the ability to be transmitted easily from birds to humans. And there is no documented case (yet) of transmission between humans; all infected humans have gotten the virus from birds.

Both papers contain basic information about genetic modifications of the virus that lead to increased transmissibility of the virus between mammals (ferrets). Government officials were worried that the information might be used by bioterrorists to create a strain of the virus that would be highly contagious between humans. When news of the papers’ potential publication first appeared back in December, the National Science Advisory Board for Biosecurity asked that publication be delayed so that the issue could be studied. However, after much discussion it has been decided that publication should be allowed after all.

Interestingly, both papers reported that modification of the virus to make it more transmissible also reduced its virulence. In fact, none of the ferrets infected with the modified viruses died. Whether the modified virus would also be less virulent in humans isn’t known. But if so, that would certainly reduce the value of the current papers to potential terrorists.

Wednesday, June 13, 2012

Finding New Uses for Old Drug Candidates

Testing potential drug candidates for safety and effectiveness is a long and expensive process.  Sometimes candidate drugs make it through the first part of the testing process (for safety) and then, either because they weren’t effective for their original purpose or for a business reason the drug company gives up on them.

A lot of money and time has already been invested in some of these drugs just to prove they are safe.  The National Institutes of Health thinks that some of these abandoned drugs could still be useful - the question is, for what?  To find out, NIH has launched a pilot project in which they’ll provide 20 million dollars in grant money in 2013 so that researchers can study these compounds, with the understanding that drug companies will make the drug candidates available to researchers.  The drug companies will retain ownership of the compounds, but the researchers will have the right to publish their findings.

It looks like a win-win situation for all.   Researchers will get access to novel compounds and the right to publish their findings.  The drug companies get free help from academic researchers in determining new uses for compounds that they otherwise would have abandoned.  And for a mere 20 million dollars in government seed money, perhaps some of these abandoned compounds will turn out to be useful after all.

Monday, June 4, 2012

Head Trauma and Brain Injuries in Soldiers

It’s becoming clear that that repeated head trauma in athletes may lead to a form of permanent brain damage called chronic traumatic encephalopathy (CTE). What about military veterans who have been exposed to blasts from roadside bombs- are they at risk for CTE, too? The answer may be “yes”, because apparently even a single strong blast can cause acute traumatic brain injury, the probable precursor to CTE. The problem of CTE actually may become much more common among veterans than in athletes – there are over 200,000 veterans who have been diagnosed with acute traumatic brain injury. No one knows how many of these veterans might develop CTE later in life.

The military is very interested in understanding how CTE could be prevented, of course. Some interesting clues were found in a recent report on brain injury in an animal model. First, researchers exposed mice to modestly traumatic blasts and documented that the mice later suffered from learning and memory deficits and the physical signs of acute traumatic brain injury. Interestingly, they then found that if they immobilized the mice’s heads during the blast, the injuries did not occur. In other words, it may not be the blast’s shock wave itself that causes the injury. Instead, the secondary high-speed blast wind apparently causes a rapid “bobble-head” movement of the head, and it is this rapid movement that may cause the injury.

I’m not sure how these new findings will lead to better prevention of CTE - perhaps helmets that reduce head movement during a blast?

Friday, June 1, 2012

Biodiesel Fuel Production Facility Planned

Two years ago a startup alternative energy company called Joule Unlimited received a patent for a process that uses genetically engineered bacteria to make biodiesel fuel from nothing more than sunlight, water, and CO2 (this blog, Sept. 20, 2010). This year the company raised $70 million in private equity to fund the construction of its first biodiesel production facility, to be built in New Mexico where harvesting solar energy is feasible.

Joule Unlimited’s biodiesel patented process is not all that different from what plants do. Plants use the same basic ingredients (sunlight, water, and CO2) to make sugars and starches. Humans can make biofuels from the sugars and starches in plants (think ethanol production from corn), but it’s expensive and requires prime agricultural land that could be put to other uses, such as growing food. Joule Unlimited’s genetically engineered bacteria make biodiesel directly. The company estimates that the process could generate up to 15,000 gallons of biodiesel per year on land that is unsuitable for agriculture, using non-potable water.

This technology could solve several problems at once if it works. One is what to do with all the excess CO2 currently being released into the atmosphere by the burning of fossil fuels. Joule Unlimited’s process turns it back into fuel, simultaneously helping to solve the second problem – a shortage of non-polluting fuel!

Disclosure: I do not have any financial interest in Joule Unlimited. I just think the company has an idea worth watching.

Sunday, May 27, 2012

Screening for Prostate Cancer Not Recommended

In a draft statement issued last fall, the Unites States Preventive Services Task Force recommended that men over the age of 75 not be screened for prostate cancer with the PSA blood test. Their argument was that prostate cancer is so slow-growing that the test was likely to do more harm than good in older men. But for men under 75 (and that’s most of us), the evidence regarding the usefulness of the PSA test was considered inconclusive.

This month, however, the task force took a much firmer stance against routine screening for prostate cancer. Its recommendation is now unequivocal; healthy men need not be screened for prostate cancer with the PSA test, regardless of age. According to the task force there is “a moderate or high certainty that the service has no net benefit or that the harms outweigh the benefits”. The task force also suggests that physicians should “discourage the use of this practice” (routine screening with the PSA test.)

The task force makes no recommendation regarding the use of the PSA test for surveillance of prostate cancer once it has been diagnosed. But healthy men, at least, can now skip the test and not feel guilty.

Wednesday, May 23, 2012

Another Way to Increase Organ Donations

As I’ve pointed out numerous times, there’s a critical shortage of cadaveric organs for transplantation into patients whose own organs have failed them. That’s why the news this month that Facebook would allow its members to list their organ donation status on their Facebook page was such welcome news. The hope is that social pressure, or at least the knowledge that their friends were doing it, would convince more people to become potential organ donors.

Researchers interested in organ donations are looking into other ways to increase organ donations as well. In one recent experiment, about half of all drivers arriving at a driver’s license renewal office to renew their license were shown a five-minute iPod video addressing common concerns about organ donation. The other half of the drivers did not see the video. Then in an exit poll, all drivers were asked to show the organ donor status written on their new licenses. 84% of the drivers who saw the video consented to be organ donors, compared to 72% of the group that did not see the video.

Apparently just a little effort to address people’s concerns about organ donation goes a long way toward convincing people to donate. Although the increase in willingness to donate after seeing the video was just 12 percentage points overall, that 12% is the equivalent of more than 40% of the 28% of drivers in the control group who chose not to donate after not seeing the video.

Monday, May 21, 2012

Is "Good" Cholesterol All That Good?

When it comes to cholesterol in your blood, all cholesterol is not the same. Statistically, people whose blood level of HDL cholesterol - the “good” cholesterol - is in the upper-normal range have reduced risks of developing heart disease. (And conversely, people whose LDL “bad”cholesterol is high have an increased risk of heart disease.) So it only makes sense that you should try to raise your HDL (and lower your LDL), right? This logic is so ingrained in us and in the medical profession that doctors routinely encourage patients with low HDL to change their diet, get more exercise, and take niacin (which is supposed to help raise HDL.) Drug companies have been trying to develop HDL-raising drugs for years - without success, I might add.

But now a new study casts serious doubt on the “good” cholesterol hypothesis. In the study, researchers reviewed the medical records of subjects with gene variations that cause the subjects to have high HDL levels. They hypothesized that subjects with high HDL because of genetic variations would have a reduced risk of heart disease. To their surprise, a high HDL due to an especially “good” genetic makeup had no effect on risk of heart disease.

So what’s going on? No one is arguing against the evidence that a high HDL is associated with a reduced risk of heart disease in normal persons, because it clearly is. But maybe the high HDL is not directly causing the reduced risk. (Remember, an association does not prove cause/effect.) And if a high HDL isn’t directly protective, then raising LDL through drugs or other means would be unlikely to be beneficial.

Incidentally, the same may not be true for the risk associated with high LDL, the “bad” cholesterol. Gene variations that caused high LDL levels were associated with increased risk of heart disease, as expected.

I’m guessing that this latest paper will lead to more research and a better understanding of the role lipoproteins play in the risk of heart disease. We need to find out, now, what’s actually lowering the risk of heart disease when we observe a high HDL, if in fact it’s not HDL itself.

Thursday, May 17, 2012

Does Repetitive Head Trauma Cause Brain Injury?

On May 2, 2012, NFL linebacker and 12-time Pro-Bowl selection Junior Seau committed suicide. He had retired in 2010 after 20 years in the NFL. His death brings up once again the very real possibility that repetitive head trauma in high-impact sports such as football may lead to a permanent degenerative brain condition called chronic traumatic encephalopathy (CTE.)

CTE can lead to depression, loss of memory, dementia, a loss of impulse control, and in the case of at least three ex-football players, perhaps even suicide. Former players are aware that there may be a looming problem with their future health, but no one knows how big the problem could be. One former player, Dave Duerson, allegedly committed suicide specifically so that his brain could be left to science for the study of CTE.

A possible association between repetitive head trauma and CTE was first proposed in 2002, when the neurofibrillary tangles that are indicative of CTE were found in the brain of deceased Pittsburgh Steeler center Mike Webster. The National Football League initially downplayed concerns, but when CTE was found in the brains of more than 50 deceased athletes who had participated in high-impact sports, the league changed its tune and has launched a comprehensive study to determine the extent of the problem.

Clearly, the NFL is between a rock and a hard place. A good, comprehensive study is sorely needed, but what if it shows that repetitive head trauma does lead to CTE? Many former players are already claiming that the dangers of repetitive head injury were ignored for too long. Over a thousand lawsuits are already pending against the NFL.

I’ll keep you posted as evidence for (or against) a causal relationship between head trauma and CTE becomes available. For now, we’re stuck with anecdotal reports, speculation, and of course, lawsuits.

Sunday, May 13, 2012

How Long Should You Breast-feed?

There’s been a lot of talk lately about a philosophy of parenting called attachment parenting. Promulgated largely by a popular child-rearing book called The Baby Book by Dr. William Sears, it’s three main tenets are: 1) breast-feeding, even for several years if mother and child wish 2) co-sleeping (baby sleeps with the parents) and 3) baby-wearing (babies are carried around in slings). The idea is that attachment parenting creates a strong bond between mother and child, so that ultimately the child grows up happier and better-adjusted.

Breast-feeding makes sense from a strictly biological perspective, whereas co-sleeping and baby-wearing confer largely psychological benefits. Breast-feeding provides partial immunity to the child against infectious diseases at a time when its immune system is not yet mature, and of course the nutritional value of breast-milk is essentially ideal. The bulk of the benefit of breast-feeding is in the first year, however. The American Academy of Pediatrics recommends that mothers breast-feed exclusively for six months, and then begin to supplement breast-feeding with solid foods until the end of the first year. Breast-feeding beyond the first year is thought to have more social and psychological benefit than biological benefit.

How do most mothers measure up? It’s complicated, because not all mothers have either the time or the inclination for attachment parenting or even for breast-feeding, especially if they work. According to the Centers for Disease Control, only 14% of babies are breast-fed exclusively until they are six months old, and only 33% are breast-fed exclusively for even the first three months. But before we get too worked up about these statistics, it’s worth remembering that although most children apparently are not breast-fed according to current recommendations, and there’s no convincing evidence that they are somehow disadvantaged as a result. So my suggestion would be that you follow the American Academy of Pediatrics guidelines if you can, but don’t feel too guilty if you can’t.

Monday, May 7, 2012

Facebook Encourages Organ Donations

Every year, nearly seven thousand of the people who are waiting for an organ transplant in the U.S. die before they ever receive an organ. The sad truth is that the number of organs available for transplant is falling farther and farther behind the growing demand for organs. Most states permit or even encourage persons to make their wishes regarding organ donation known on their driver’s licenses. And yet, fewer than half of all adults have indicated that they would be willing to be an organ donor in the event of their untimely death.

In what some people see as a move from social networking into social engineering, Facebook announced last week that it would encourage its members to list their donor status on their Facebook pages. Experts in the field of organ donation are pleased. It’s one thing to decide in private to be an organ donor – its quite another to make a public statement by announcing it to all of your friends. The hope is that peer pressure will cause some of the 160 million Facebook members in the United States (and 900 million worldwide) to join the organ donation bandwagon, adding millions of persons to the potential organ donor pool.

I’d like to see that happen. Though I’m not a Facebooker, I am proud to be a a potential organ donor. How about you?

Thursday, May 3, 2012

Testing Young Athletes for Heart Disease

Sudden death from heart disease is rare in young persons. However, the risk of sudden death is almost three times greater among athletes in high-risk sports such as basketball, football, and soccer, just because of the very physical nature of these sports. Approximately 90 young competitive athletes die suddenly each year from undiagnosed underlying heart disease. Is this enough deaths to warrant mandatory screening of all young athletes for underlying heart disease?

Sudden death from cardiac disease in young persons usually is due to either a problem with the electrical activity of the heart or to a condition called hypertrophic cardiomyopathy, a long way of saying that the heart muscle is abnormally thickened. Both conditions could be detected by an ECG (electrocardiogram). But an ECG is fairly expensive – more than $1,000 without insurance – which might prohibit some young athletes from participating in sports if it were required.

The American Heart Association does not yet recommend mandatory screening of all young athletes for heart disease, in part because of the high cost versus the small number of people who would benefit. However, a fairly recent paper in the Annals of Internal Medicine indicates that screening for heart disease might actually be cost-effective. The study’s authors estimate the long-term costs to society of treatment of cardiac disease in athletes found to test positive, as well as estimates of how many life years would be saved. The study finds that ECG screening would save an additional two life years for every 1,000 athletes tested, at a net cost of under $90 per athlete, compared to the current standard of just a history and physical.

Ultimately, someone will have to decide whether ECG testing of student athletes would be worth it. For now, it’s not required.

Friday, April 20, 2012

Can Genes be Patented?

After several years of court battles and reversals of previous court decisions, there’s still no final decision on whether or not a human gene variant can be patented (see "Patenting Human Genes - An Update.") A company called Myriad Genetics believes that it holds a valid patent on the two gene variants known to confer a high risk of breast cancer, called BRCA1 and BRCA2. The company makes over 80% of its total revenue (over $350 million a year) from its BRACAnalysisR test for the presence of the gene.

To bring you up to date since my last post on this issue, two lower courts ruled that the patent was invalid. Then in 2011 the U.S. Court of Appeals for the Federal Circuit reversed the decision of the lower courts, ruling that the Myriad Genetics patents on the BRCA1 and BRCA2 genes were valid. But that was not the end of it. Last month the U.S. Supreme court issued a statement that it would “vacate”, or dismiss the Court of Appeals’ decision. In effect, the Supreme Court kicked the case back to the Court of Appeals “for further consideration”. It’s a gentle way of asking the lower court to reconsider their decision, without the Supreme Court itself having to issue a ruling.

In a previous decision in an unrelated case, the Supreme Court made it clear that structures or processes governed by “the laws of nature” cannot be patented. By kicking the Myriad Genetics case back down to the Court of Appeals, the Supreme Court seems to be asking the Court of Appeals to consider carefully whether the sequence of a gene is governed by the laws of nature, and hence not patent-eligible.

As long as the issue remains undecided, Myriad Genetics continues to have exclusive control over the BRCA gene test and will continue to profit from it. Given the way the Supreme Court seems to be leaning on this issue, it may be in Myriad Genetic’s best interest to drag the court battle out as long as possible. We can expect the company to defend its putative patent vigorously once the Court of Appeals takes up the case again.

Sunday, April 15, 2012

The High Cost of Specialty Drugs

Generally speaking, the smaller the market for a drug, the more expensive the drug is. That’s because it costs a lot to develop, test, and market a new drug – on the order of $500 million or more. The pharmaceutical company must eventually recover those costs through drug sales or they couldn’t stay in business. As a result, some drugs, called “specialty drugs” because so few patients need them, can cost upwards of $100,000 per year.

Who should pay for the high cost of specialty drugs? Insurance companies argue that these drugs are costing them too much, and they’d like to shift some of the cost to the patients in the form of co-pays on the order of 30% or more. But some patients worry that even at $30,000, they still won’t be able to pay for their drugs. Responding to public pressure from patient’s advocacy groups, at least 20 states have passed or are at least considering laws that would limit the out-of-pocket drug expenses to patients. And they have surprising allies – the very pharmaceutical companies that manufacture and sell these expensive drugs. That’s because the drug companies know that high co-payments discourage patients from taking their medications, thereby lowering drug sales. In some cases pharmaceutical company representatives have even helped state legislators draft the legislation!

The impending federal health care law (now called Obamacare by many politicians) would also set limits how much patients have to pay for drugs. But the law doesn't take full effect until 2014, and right now no one knows whether or not the law will still be in effect by that time. In the meantime, the issue of who pays for really expensive drugs is being resolved state by state.

Thursday, April 12, 2012

Limiting Antibiotic Use in Farm Animals

On Jan. 7, 2012 on this blog, I suggested that the FDA would probably not try to limit the indiscriminate use of antibiotics in farm animals until the problem of antibiotic resistance got much worse. I’m happy to say I may have been wrong. This week the FDA announced that it is issuing “guidance” to farmers, veterinarians, and drug companies in an attempt to get them to voluntarily use fewer antibiotics solely to increase meat or milk yield in healthy animals. The animal agriculture industry uses nearly 30 million pounds of antibiotics per year, mostly in animal feed, even when the animals are healthy.

Compliance with the FDA’s new guidance will be voluntary for now. That leaves one wondering whether it’ll have any real effect. But apparently the FDA is serious about this. The FDA has promised to monitor the usage of antibiotics over the next three years. If antibiotic use does not decline as the FDA hopes, the FDA will “…consider further action as warranted….”. The message to the animal agriculture industry is clear; reduce the use of antibiotics voluntarily, or we’ll reduce it for you. 

It’s the right approach. The FDA is well aware that the meat production industry relies heavily on antibiotics to increase yield. The agency has no desire to disrupt a major U.S. industry unnecessarily. Yes, it’s important that we do something to try to do something about the current rapid rate of development of antibiotic resistance, but that has to be balanced against the potential negative consequences of taking too severe an action too quickly. The FDA’s attempt at a little arm-twisting might just work. And if it doesn’t, action can always be taken later.

Monday, April 9, 2012

FDA Not Ready to Ban BPA

In response to a petition from the Natural Resources Defense Council (NRDC) that bisphenol A (BPA) be banned from food packaging, the Food and Drug Administration (FDA) says that there is not enough scientific evidence that BPA is harmful to humans to warrant banning the chemical at this time. It’s a predictable and defensible statement from a government agency charged with safeguarding the public health. How else should they act without evidence?

BPA is used as a softening agent in hard plastics such as reusable water bottles and baby bottles, and in the plastic lining of food cans. It belongs to a class of chemicals called “endocrine disruptors” that mimic the effects of the hormone estrogen. In animal studies, toxic doses of BPA may disrupt growth and development or cause endocrine or nervous system disorders. No one knows for sure if it’s harmful at the much lower doses to which humans are exposed, but many consumers continue to be concerned.

The FDA continues to study the health effects of BPA. The agency is likely to act quickly if evidence of harm ever emerges. In the meantime, for people who remain concerned the agency offers advice on how to limit one’s exposure to the chemical.

Companies that make consumer products, on the other hand, don’t feel obligated to wait for scientifically defensible evidence – the court of public opinion is enough for them. Baby-bottle makers and some canned food companies are already searching for alternatives and phasing out their use of the chemical wherever possible.

Tuesday, April 3, 2012

Abstinence Doesn’t Resonate with Teens

Teen pregnancy and birth rates vary widely by state, according to the Centers for Disease Control and Prevention (CDC). The highest rates were in five southern states; Arkansas, Mississippi, New Mexico, Oklahoma, and Texas. Mississippi topped the list, with 65.7 births per 1,000 teens aged 15-19 in 2008. The lowest rates were in four northeastern states; Connecticut, New Hampshire, Massachusetts and Vermont. New Hampshire had the lowest teen pregnancy rate, with only 19.8 births per 1,000 teens.

The Guttmacher Institute, a non-profit organization focused on sexual and reproductive health and education, was quick to point out that the five states with the highest teen birth rates all require that abstinence be stressed in their education programs on sex or HIV, whereas none of four states with the lowest rates specifically require that abstinence be stressed. The implication is that teen birth rates are lower when students are provided with comprehensive, evidence-based sex education than when they are just told that abstinence is a goal.

Critics of the findings say that there are many other differences between the states with the highest and the lowest teen pregnancy rates, including racial and cultural differences. However, the disparities remain even when race is factored out.

Of course a correlation does not prove causation. But it’s still an interesting hypothesis, that stressing abstinence is not an effective way to reduce teen pregnancies.

Saturday, March 31, 2012

Aspirin and Cancer

The evidence continues to accumulate that daily doses of aspirin reduce the risks of developing certain cancers. The most recent report is a summary of 34 previous studies (with a combined total of nearly 70,000 participants) in which aspirin was recommended for the prevention of deaths from vascular disease. When the authors of the report re-examined the data from the previous studies for cancer deaths, they found that a daily dose of aspirin for just three years reduced risk of dying of cancer by 24%, compared to study participants not taking aspirin. And by five years the reduction in cancer deaths was 37%. The greatest reductions in deaths were from esophageal and colorectal cancers.

The results were so striking that it’s tempting to argue that everyone should be taking aspirin for the prevention of cancer. The problem for doctors and their patients is that aspirin has some negative side effects, including gastrointestinal bleeding and an increased risk of hemorrhagic strokes. Doctors are still reluctant to recommend that everyone should be taking low-dose aspirin specifically for cancer prevention. However the new findings may cause a shift in thinking about the usefulness of aspirin in persons with a past history of certain cancers or with a family history of cancer.

Monday, March 26, 2012

First Federal Anti-Smoking Ad Campaign

Perhaps you’ve seen the hard-hitting anti-smoking ad featuring “Terri”, who offers her tips for getting ready to go out in the morning. It might surprise you that the sponsor of the ad is neither a state government nor an anti-cancer organization such as the American Cancer Society. It’s the U.S. government. The ads are part of a campaign by the Centers for Disease Control and Prevention (CDC) to directly address the high rate of tobacco addiction in the U.S. This is the first time the government has ever gotten directly involved in anti-smoking advertising.

The government is spending just $54 million on the campaign this year - less than a tenth of what is spent on anti-smoking campaigns by the states. The CDC has been recommending even higher rates of spending for tobacco prevention and control by the states for years, and the states just haven’t been able to reach the CDC’s spending targets. In fact, state spending on anti-smoking campaigns declined by 11% in 2011. Perhaps that’s why the CDC felt it needed to get into the anti-smoking ad business itself, instead of leaving it to the states.

The new CDC-funded ads are more graphic than what we’re used to, and somewhat controversial. Smokers have called them demeaning. What do you think – will they have any greater impact on smokers (or potential smokers) than the ads of the past?

Sunday, March 25, 2012

Coronary Artery Stents are Not Effective

For some time now, a popular method for treating stable coronary artery disease (a coronary artery narrowed by atherosclerotic plaque) has been to implant a stent in the affected area. A stent is an expandable metal mesh tube on the tip of a long catheter. The stent is inserted into an artery in an arm or leg and then threaded up into the coronary artery to the point of narrowing. Once in place, the stent is expanded to widen the coronary artery. The catheter is then withdrawn, leaving the stent in place.

Stents are sometimes preferred over coronary artery bypass graft (CABG) surgery because stents do not require open-chest surgery. In addition, the symptoms of stable coronary artery disease (such as a type of heart pain called angina) tend to go away right after surgery. Typically the patient is back on his/her feet within a day or two. Surgeons and hospitals like stents, too, because at $30,000 - $50,000 per patient, they are big money makers.

Unfortunately, a recent review of over 7,000 patients enrolled in eight different clinical trials showed that stents have little or no advantage over standard medical care with drugs. About half of the patients in the studies were given stents plus standard medical care (treatment with beta-blockers, statins, aspirin, or ACE inhibitors). The other half of the patients received just the standard medical care. Four years later, there were no differences in patient outcomes between the two groups in terms of reduced angina, fewer heart attacks, or death.

Will this new information affect the number of stents implanted every year? Time will tell. But in the interest of informed consent, I hope that the information will be at least given to patients before they choose to have a stent implanted.

Saturday, March 17, 2012

New Guidelines Advise Less Frequent Pap Tests

The United States Preventive Services Task Force issued new guidelines this week for the frequency at which women should be screened for cervical cancer with the Pap test. The new guidelines are based on statistical analysis that tries to identify the balance point between the risk of not doing the test often enough (not detecting a cancer), versus the potential harm of doing the test too often (false positives can lead to painful biopsies, emotional stress, and a risk of pregnancy complications in the future). That balance point is different for different age groups, based on their likelihood of developing cervical cancer at that age. The new guidelines call for less frequent tests, especially among women in the youngest and the oldest age groups in which the risks of cervical cancer are relatively low.

Specifically, the guidelines recommend that women should not be screened for cervical cancer with the Pap test until they are 21 years old. Between 21 and 29 they should have a Pap test only once every three years, instead of every year. Between 30 and 65, women should either have a Pap test every three years, OR a Pap test every five years if it is combined with a test for HPV. Women over 65 need not be screened at all, provided they are healthy.

The American Cancer Society agrees with the new recommendations, and has already incorporated them into their cancer screening guidelines posted on their website.

Thursday, March 8, 2012

Advertising for a Kidney on

A 28-year-old Florida woman who desperately needed a kidney transplant made a plea last summer on for a person willing to donate one to her, according to an article in USA Today. After the local television channel picked it up as a news story, she received over 800 inquiries and finally found a willing donor who was a good match - a 23-year-old woman who lived nearby. The two women traveled together to the hospital for psychosocial evaluations and medical tests. Eventually the hospital gave its approval, and the donation/transplant was performed in December. Both women are doing well.

Placing an ad on Craigslist or other Web site for a kidney is a bit unusual, but not illegal as long as the donor is not paid for the kidney. The donor’s medical expenses can be paid, but no other compensation is allowed. The reason for the psychosocial evaluations is to ensure that the motivation of the donor is purely altruistic and that he/she knows all of the possible medical and psychosocial risks. 

The only benefit to an altruistic organ donor is the knowledge that they have done something truly selfless for another person. And for a rare few, that apparently is enough. How rare? Less than 2% of all living donors are strangers to the recipient.