Historic Climate Change Deal Signed

At a historic meeting in Paris this month, 195 nations have finally agreed on a deal to try to curb worldwide emissions of greenhouse gases in an effort to slow the rate of climate change. Although the specifics of the deal are not entirely spelled out, a core requirement of the deal is that every country must do something, and that their goals must be clearly spelled out and made public. The deal is at least recognition for the need to make progress. The countries will reconvene every five years to review their individual and collective progress and to update their plans.

Not everyone is entirely happy with the deal, of course. Poor countries want money to help them cope with the costs, and even some leeway (in terms of greenhouse gas creation) to catch up economically with rich countries, which they say have caused most of the global warming so far. And many people in the U.S. still question the science of climate change and/or the need for action, because any action taken will almost certainly have a high economic cost.

The winners will be innovators in new technologies such as solar and wind power, battery and energy storage technology, electric cars, energy efficiencies in the home and industry, and so on. Losers are likely to be the coal industry, and to a lesser extent oil and gas. But any shifts in fortunes are likely to take place over decades, not months or years.

Expect to hear more about what the U.S. pledges to do, and to experience the effects, in the coming years.

Gut Bacteria Can Alter Energy Efficiency

Why do some people seem to stay thin no matter what they eat, whereas others struggle with obesity despite trying to limit their caloric intake? One factor is genetics; you're stuck with the genes and hence (at least in general terms), the same body type and energy metabolism that you inherited from your parents. Another factor, it seems, is the bacteria in your gut.

A key experiment showing the role of gut bacteria in nutrient absorption was published several years ago (see this blog, Sept. 11, 2013). The authors of the study wondered why twins sometimes were discordant for obesity (showed different tendencies toward obesity), and they suspected that gut bacteria were involved. To find out, they took samples of the gut bacteria from twins discordant for obesity, and gave those samples to mice. Lo and behold, the mice that received bacteria from an obese twin gained more weight than mice given bacteria from the non-obese twin.

Experiments published recently in Cell take the gut bacteria affect energy efficiency hypothesis one step further. In these experiments, researchers exposed mice to either a normal temperature environment (22 degrees Centigrade) or a cold environment (6 degrees C). Both groups were fed exactly the same number of calories per day. As expected, the mice in the cold environment initially lost weight as they burned fat to stay warm. But then something interesting happened; they began to gain weight again. When researchers examined the feces of both groups, they found that the cold mice had become 50% more efficient at absorbing nutrients from their food. Further examination revealed that the cold mice lacked a particular strain of gut bacteria. When mice in a normal temperature environment were given those bacteria, they gained weight.

Bottom line; it's possible that your ability to gain or lose weight may be influenced by gut bacteria. Although I pooh-poohed the idea back in 2013, there may just be the possibility that in the future, modifying your gut biome might actually become an effective dieting tool. We'll see; more research is needed.

Increased Mortality Among Middle-Aged Whites

Mortality rates for most age- and racial-groups have declined over the past several decades. But among middle-aged whites, the mortality rate has actually increased. No other rich country has shown such a trend. Among poorly-educated white non-Hispanic Americans between the ages of 45 and 54, for example, mortality rate increased more than 10% between 1999 and 2013.

The culprit, it appears, is not one or more of the chronic diseases usually associated with more developed countries, such as obesity, diabetes, heart disease, stroke, and cancer. The main causes are suicides, and deaths due to drugs and alcohol, according to research published in the Proceedings of the National Academy of Sciences. These are generally signs of stress in a population, not consequences of affluence.

Although the mortality rate for middle-aged whites is the only mortality rate that is rising at the moment, it's still 40% lower than that for blacks. So perhaps we shouldn't make too much of this recent finding, except that it may tell us that in the future we'll have to focus on mental health and the sense of well-being for all racial groups, if we are to make any additional progress on mortality rates.

Survival Rates After a Cardiac Arrest

If you're going to experience a cardiac arrest (complete cessation of a heartbeat), it's best to do it in Seattle.

Cardiopulmonary resuscitation (CPR) always seems to work on the medical TV shows. But in truth, the chances of recovering from a cardiac arrest aren't all that good. Outside a hospital the average survival rate of patients eventually treated by an emergency medical service (EMS) is less than 10%; even in a hospital it's only about 20%. Survival rates vary considerably depending on where the patient undergoes a cardiac arrest. In Detroit the survival rate is only 3%; in Seattle it's 20%, according to an article in the New York Times.

The four components of CPR are chest compression, ventilation (breathing for the patient), defibrillation (shocking the heart to get it started again), and epinephrine. The first two can be done by amateurs (passers-by) and can be fairly effective as a stopgap measure if done right. The latter two require EMS staff. And the key to improved survival seems to be better education of amateurs and training and monitoring of EMS staff. Seattle, for example, has a long history of an emphasis on CPR awareness and education of amateurs, combined with continual training and monitoring of the success of EMS staff.

Keys to good CPR are that it should be done vigorously and for longer than most people think. If you ever are in a position to try to save a patient while waiting for the EMS, don't stop chest compressions for longer than 10 seconds at a time while searching for a pulse, and don't give up too soon. Cardiac compression can be tiring for the resuscitator, but an hour of compression rather than just 15 minutes can sometimes save a patient.

If you're not trained in CPR yet, you might consider taking a basic CPR training class. The Red Cross and the American Heart Association offer them on a regular basis.

An HIV-Preventing Drug Exists, But Isn't Being Used

Back in 2012, the FDA approved the first drug for the prevention of HIV infection in otherwise healthy persons who might be at risk for infection due to exposure to an infected partner. The drug, called Truvada, prevents HIV infections 92% of the time, meaning that it could sharply reduce the number of new HIV infections if it were widely used. That turns out to be a big "if", for hardly anyone seems to be using the drug.

The drug's manufacturer, Gilead Sciences, Inc., has made a lot of money ($1.8 billion in 2014) from the use of the drug to treat HIV-infected patients. But it has made no effort to market Truvada for use in healthy persons solely for the purpose of preventing HIV infection. The company says that it just isn't profitable to market the drug for HIV prevention. And as a result of a lack of marketing, many physicians and nurses are simply unaware that the drug has been approved and is available for HIV prevention. According to the Centers for Disease Control and Prevention (CDC), one in three primary care doctors and nurses have never even heard of the potential use of Truvada for what is called preexposure prophylaxis (PrEP).

Lesson learned: government health officials will have to take the greater role in educating primary care physicians and nurses about Truvada for PrEP. Health officials in New York are already doing so according to the CDC, and as a result the number of NY medicaid beneficiaries receiving PrEP more than quadrupled between 2014 and 2015.

First Uterus Transplant in the U.S.

If all goes according to plan, surgeons at the Cleveland Clinic will perform the first U.S. transplantation of a uterus within the next few months according to an article in The New York Times. Eight women are currently being evaluated as the possible first candidate for the procedure. All eight are women who were either born without a uterus, or whose uterus was surgically removed or damaged at some point.

Why hasn't it be done before, you might ask? The primary reason is that extensive and risky procedures such as organ transplants have traditionally been done only to save the life of the patient. But the women who want this uterine transplant are medically healthy, except for the inability to have the experience of having a baby. The procedure will be risky, both for the mother and the baby. The surgery itself will be extensive. And the mother will most likely have to take tissue rejection drugs throughout pregnancy, which could affect the fetus. In the worst case scenario, if the uterus is rejected during pregnancy, there goes the fetus as well.

I'm not against the procedure necessarily; if a woman wants to pay hundreds of thousands of dollars and take the risk, that would be her choice. What I am against is having uterine transplants become so routine that eventually you and I are asked to pay for them via health insurance. Let's face it, uterine transplantation would be a selfish act by an otherwise healthy woman who simply insists on experiencing pregnancy and childbirth. It has very little to do with wanting to raise a child; for that there is adoption, or surrogacy if the couple insists on raising a child with only their genes.

That's just my opinion. What's yours?

China To Allow Two Children Per Couple

Back in 1979, China introduced a one-child-per-couple policy in order to curb what it saw as too high a rate of population growth. The country offered government subsidies for only the first child; levied fines for having more than one child; in some cases even resorted to sterilizations and forced abortions in an effort to enforce the rule. The policy was so effective that by 2000 the national fertility rate was only 1.5, well below the fertility rate of 2.1 at which a population stabilizes. Even worse, the policy has led to a newborn sex ratio of 116 boys to 100 girls; if they are only allowed to have one child, most Chinese couples would prefer that it be a boy.

In recent years China has begun to realize that the country will face a shortage of workers to support an aging population if current trends continued. In 2013 China relaxed the one-child policy somewhat by allowing people who were an only child to have a second child. And last month, China revised its policy to allow all couples to have two children, according to a CNN news article. However, it may be a case of too little, too late; even if the fertility rate does rise to 2.0 by 2050, the overall population will rise increase only 2% - hardly enough to take care of all those over-65 retired people.

One thing the new policy may do, however, is reverse the trend toward an over-abundance of male children. And that may ultimately improve marriage prospects for young Chinese males, who currently find it hard to find a suitable mate.

The First Amendment and Off-Label Drug Marketing

Should a pharmaceutical company be allowed to actively promote and market a drug for off-label (unapproved by the FDA) use? Consider, for example, a drug that lowers triglycerides, called Vascepta. The FDA has approved it only for patients with extremely high triglyceride levels, because in these patients the drug has been proven to lower the risk of heart disease. However, the drug is not approved for patients with "only" very high or high triglycerides, because there is no proof that it actually lowers the risk of heart disease in these patients.

Understandably, the drug company wants to sell the drug to as many patients as possible, and there are at least 10 times more patients with lesser elevations of triglycerides than there are patients with extremely high triglycerides. So the company sued the FDA, saying that under the First Amendment (freedom of speech), they have the right to promote the drug to patients as a triglyceride-lowering drug, even though there's no evidence that it would benefit them in terms of reducing the risk of heart disease. The FDA disagreed, arguing that under a 1962 law, drugs are only approved when they have been proven both safe and effective at reducing the risk of a medical relevant condition.

In August a federal District Court judge ruled that the drug company could promote the drug as a triglyceride-lowering agent because it's a true statement, and therefore is protected by the First Amendment. Requiring additional evidence of clinical effectiveness, according to the judge, would be suppression of free speech. The ruling in effect ties the FDA's hands in terms of requiring that drugs actually do something important before they can be marketed.

If the court ruling stands, we may be entering an era where drugs are promoted directly to the public because they do something measurable (in this case, lower triglycerides), without evidence that they are clinically effective (in this case, reduce the risk of heart disease). Rest assured that in their marketing campaigns, the drug companies will do everything in their power to imply that their drugs do something useful, without actually saying it. Even though we might agree that protection of free speech is important, is this truly in the public's best interest?

It's not clear whether the FDA will appeal the ruling to the Supreme Court, but this one is worth watching.

Mortality Trends in the United States, 1969-2013

For all the money spent on health care research, are we making any progress towards reducing mortality from some of the major health problems? Where might more research be needed?

To find out, researchers affiliated with the American Cancer Society analyzed trends in age-standardized mortality rates from 1969 through 2013 for six major killers; heart disease, cancer, stroke, chronic obstructive pulmonary disease (COPD), unintentional injuries, and diabetes mellitus. ("Age-standardized" mortality rates take into account the changing age structure of a population over time.)

The data show that we are indeed making progress overall. From 1969 to 2013 the overall age-standardized death rate per 100,000 fell from 1278.8 to 729.8; a decline of 43%. For specific conditions, the mortality rate from stroke declined 77%; from heart disease 68%; from unintentional injuries 40%; from cancer 18%; and from diabetes mellitus 16%. However, the change in mortality rate from COPD was a real shock; it increased over 100% over the same time period.

The 100% increase in COPD is troubling, but this research doesn't provide any answers regarding the reason. One possibility is that we may be seeing the delayed consequences of the much higher popularity of smoking in past decades. But that's a question that would need to be examined by further research.

23andme Gains FDA Approval

Remember 23andme, the genetic testing company that got chastised by the FDA for providing what the FDA called a "medical device" without the proper documentation? (See this blog, Dec. 5, 2013.) Well, they're back in action again, this time with FDA approval.

Back in 2013, 23andme was offering to analyze samples of saliva and provide "health reports on 254 diseases and conditions" for just $99. The sticking point for the FDA was that the company was providing estimates of a person's risk for developing various genetic diseases and conditions, such as Alzheimer's disease; information that the FDA said was tantamount to offering a medical device without proof of the accuracy of the risk estimates the device provided. The company was ordered to stop providing risk estimates until proof of their accuracy was provided.

Against what seemed like formidable odds, the company stayed in business, providing information on ancestry instead. And they went to work to satisfy certain requirements of the FDA. Now they're back, this time providing information that IS acceptable to the FDA. For just $199 (notice that the price has doubled!) the company now provides basic information about a person's genetic "carrier" status for just 36 conditions, including cystic fibrosis and sickle cell anemia. While that may not seem like much, such information could be useful to prospective parents who want to know their chances of passing these genetic mutations on to their children before they make the decision to have children.

The company says that they still hope to provide accurate, defensible personal risk information for certain diseases (such as the risk of developing Alzheimer's disease later in life) in the future. And who knows, maybe they will. I didn't think the company would ever survive the debacle of 2013, but they did.

New American Cancer Society Guidelines for Mammograms

The American Cancer Society, which traditionally has taken an aggressive position towards screening for breast cancer, has softened its stance on the need for mammograms to detect breast cancer. The new guidelines are published in the Oct. 20 issue of JAMA, along with an editorial summarizing the new recommendations.

Previously, the cancer society had been recommending yearly mammograms after the age of 40. The new guidelines recommend that women have annual mammograms starting at the age of 45, and then only every other year after the age of 54 provided that they are healthy and not at high risk of breast cancer. That brings the cancer society's recommendations more in line with the United States Preventive Services Task Force (USPSTF), which recommends biennial mammograms only after the age of 50. In addition, the ACA no longer recommends clinical manual breast exams (in which the health care provider feels for lumps) at any age.

The new guidelines reflect the latest scientific evidence that annual mammograms are not very useful in younger women and that they can result in false positive results, leading to unnecessary additional tests, including biopsies. However, don't expect physicians or patients (who've been conditioned for decades to fear cancer and to take any possible action against it) to immediately accept the new guidelines. There will still be those who take a "better safe than sorry" approach and continue with their yearly mammograms.

Natural Defenses Against Cancer

We now know that cancer is a disease of a loss of control over cell division. A commonly-held belief is that larger animals such as humans (with more cells and hence more cell divisions) and animals that live a long time (with more opportunity for cell damage to occur over time) should be more prone to cancer than smaller, short-lived animals.

A recent study shows that the size-and-time belief is incorrect. In a study of 36 mammalian species, the authors found no evidence of increased incidence of cancer in larger or longer-lived animals. Elephants live much longer than humans and have many more cells, but fewer than 5% die of cancer, compared to a cancer death rate of 11-25% in humans. And a particular strain of rat called the naked mole rat lives up to 30 years - much longer than other rats - without being prone to cancer. So the question becomes, why is that?

It turns out that nature has developed defenses against cancer. During evolution, elephants developed extra copies of a cancer-fighting gene called p53. (Humans have one copy; elephants have more than 20.) The p53 gene causes damaged cells to commit suicide, effectively preventing them from becoming cancerous. The naked mole rat developed a protein that blocks the growth of fast-dividing (potentially cancerous) cells.

Researching the natural defenses against cancer in other long-lived or large animals might help us better understand how cancer develops in humans and how best to fight it.

Express Scripts Will Cover the Newest (Expensive) Cholesterol-Lowering Drugs

 I posted a blog recently about the two newest cholesterol-lowering drugs, made by Amgen and Sanofi SA (See this blog, Oct. 6, 2015). The new drugs will be very expensive; approximately $14,000 per year, compared to just a few dollars a month for the statins. I raised the question about whether insurers should cover the new drugs just because patients say they want them.

When the prices of the new drugs were announced, it seemed that the intent was to limit the use of the drugs to those patients who couldn't achieve adequate cholesterol reduction with the statins. According to FoxNews, insurers planned to "aggressively challenge" claims of statin intolerance before agreeing to pay for them. But how will insurers respond when physicians write prescriptions for the new drugs for their patients? I'm betting that patients will demand the new drugs once the drug companies start their ad campaigns, and that insurers will be pressured into paying the exorbitant bill.

At least one pharmacy benefits management company, Express Scripts, has included the new drugs in its 2016 list of approved drugs, but the company added that there would be "restrictions" on who could use them. Good luck with that! It will be interesting to see whether they actually do manage to restrict their use, or whether the costs to insurers will spiral out of control.

If you think it doesn't matter, consider this; high health insurance expenses by other insured individuals ultimately affects your insurance rates.

Governor Brown Signs California's Death with Dignity Bill

Last week California governor Jerry Brown signed the state's death with dignity bill, known officially as the End Of Life Option Act. The bill, inspired by the plight of Californian Brittany Maynard who had to move to Oregon to take advantage of a similar law there, will take effect next year. In a statement made after the signing, governor Brown said, "I do not know what I would do if I were dying in prolonged and excruciating pain. I am certain, however, that it would be a comfort to be able to consider the options afforded by this bill." Governor Brown consulted with doctors and a Catholic bishop before he made his decision to sign the bill.

Opponents of the bill have already begun efforts to have the bill repealed. They'll have an uphill battle; a recent poll showed that 65% of Californians approve of the bill, while only 27% oppose it.

Do Some People Have a "WiFi Allergy"?

Is it possible for people to have an allergy, or at least an adverse reaction of some kind, to WiFi transmissions? Some people think so. They claim that their symptoms of headaches, itchy skin, a rash, heart palpitations and nausea are caused by what they call an "electromagnetic hypersensitivity" (abbreviated EHS; doesn't every disease have a three-letter designation these days?), which can be triggered by wireless Internet service transmissions. One couple has even sued their son's school, claiming that EHS is a disability and that the school must change their WiFi system to accommodate him.

It turns out that many cases of EHS are self-diagnosed. The condition is not a recognized medical diagnosis by any authoritative medical body. Although no one denies that some people experience symptoms, it appears that the symptoms result more from what is called a "nocebo effect" - the tendency for someone to feel unwell when they think they have been exposed to something hazardous. In a review published in 2010 of 46 published blind or double-blind studies, involving over 1,000 people who self-diagnosed themselves has having EHS, it was found that reactions similar to EHS were elicited when the persons thought they were being exposed but were not. In other words, the symptoms in these patients are most likely due to psychological factors.

Nevertheless, some people continue to push for EHS to be declared a disability, entitling them to the accommodation that such a declaration would allow. Let's hope they don't succeed.

New Drugs For Lowering Cholesterol

The Food and Drug Administration (FDA) recently approved two new drugs for lowering LDL, the "bad" cholesterol. The new drugs work by an entirely different mechanism from the current gold-standard cholesterol lowering drugs, the statins. The new drugs mimic the effect of a genetic mutation, described in two patients several years ago, that results in very low LDL levels (see this blog July 18, 2013). The two drugs, Praluent, made by Sanofi Regeneron, and Repatha, made by Amgen, should be available soon.

Now for the bad news; the new drugs will cost upwards of $14,000 a year. For most patients who need of a cholesterol-lowering drug, there will be no reason to switch from a statin to one of the new drugs. But some patients say (rightly or wrongly) that the statins cause them to have muscle pain, hazy memory, and problems sleeping.

Should health insurers pay for the new (expensive) drugs just become some patients say they can't tolerate the statins? Double blind studies have shown that patients taking statins have no more muscle pains than patients taking a placebo. Muscle pain is such a common complaint in the age group of patients likely to be taking cholesterol-lowering drugs that it's hard to pinpoint the source.

I guess the question is, should patients' perceptions trump good science? Or should the insurance companies just say "no"?

What is the "Ideal" Systolic Blood Pressure?

Current guidelines for treating high blood pressure are that anyone with systolic blood pressures of 140 mmHg or above (or diastolic pressures above 90mmHg) should be treated to lower their blood pressures below those numbers. But the guidelines beg the question; is there an ideal systolic pressure that is even lower than 140?

According to a recent article in the New York Times, a major new research study shows that lowering systolic pressure to 120 or below reduces the risk of heart attacks, heart failure and strokes by a quarter and reduces the risk of death by a third, compared to just lowering systolic pressure to 140 or below. The findings imply that treatment of high blood pressure should be much more aggressive than the current guidelines suggest.

However, a closer reading of the actual study design reveals an important point: the study examined only patients who are already at risk for heart disease. These were not normal healthy people who just happened to have systolic pressures of 130 mmHg; they were all subjects with systolic blood pressures above 130 mmHg who also had evidence of cardiovascular disease, chronic kidney disease, cardiovascular disease risk factors, or were older than 75.

The results are clear; patients at high risk of cardiovascular disease should be treated more aggressively than in the past, with a goal of lowering their systolic pressures to 120 mmHg or less. But what about normal people who just happen to have a systolic pressure of greater than 120 mmHg? Cardiologists may begin recommending that they be treated, too (to the delight of the companies selling antihypertensive drugs.) But I'm not so sure. All drugs have side effects: when drugs are recommended, the potential benefits should outweigh the risks. And we just don't know whether lowering systolic blood pressure to below 120 in otherwise healthy people is a good idea.

Forest Fires and Global Warming

The recent spate of forest fires in the Western United States raises an interesting question; to what extent are the recent increases in Western forest fires linked to global warming? And more importantly, to what extent could the fires themselves contribute to global warming?

According to a recent article in The Economist, the National Research Council estimates that for every degree of global warming, the amount of Western land burned in North America each year could quadruple. With an estimated 2-degree increase global temperatures expected by the end of this century, that would be a 16-fold increase in land burned by forest fires by 2100. Sixteen-fold!

But this is where it gets really interesting. Trees absorb CO2 from the atmosphere as they grow, and they release that CO2 into the atmosphere when they are burned. So not only do forest fires add CO2 to the atmosphere, exacerbating the global warming trend; they also reduce the number of trees available to absorb CO2.

It's not going to be pretty for our descendants if we can't get global warming under control soon.

Are Antimicrobial Soaps Effective?

Do antibacterial soaps protect you against dangerous bacteria? The answer is probably not.

In a study published in the Journal of Antimicrobial Chemotherapy, researchers examined the effectiveness antimicrobial liquid soaps containing triclosan, the most common ingredient in these soaps. First, they exposed 20 different strains of harmful bacteria to the soaps in petri dishes. The antimicrobial soaps did kill the bacteria, but only after 9 hours or more of exposure. Then, to test the effectiveness of the antimicrobial soaps under more real-world conditions, they spread bacteria on the hands of volunteers and asked them to wash their hands in cold water for 30 seconds with either antimicrobial or normal (non-antibacterial) soaps. Under these conditions, there was no difference between the antimicrobial soaps and the normal soaps in terms of their ability to kill the bacteria.

The bottom line is that antimicrobial soaps containing triclosan do have antimicrobial properties under certain conditions (9 hours!), but they are not effective under ordinary hand-washing conditions. It's something to think about, especially since any exposure to antimicrobial agents is likely to increase antibiotic resistance to that antimicrobial agent in the long run.

On a totally unrelated subject, it's a pet peeve of mine that the original article in the Journal of Antimicrobial Therapy is not available to the public for free; you can only see the abstract. If it's important information that was funded by public funds, it should be available to the public. In this particular case you can get more information from the popular press than from the journal itself. And that's a shame.

California Legislature Passes a Death With Dignity Bill

The California legislature passed a bill last week that would allow physicians to prescribe a life-terminating drug for terminally ill patients under certain circumstances. Called the End Of Life Option Act, the bill would require that a person be evaluated by at least two physicians, both of whom would have to declare that the person has less than six months to live. In addition, the patient would have to submit a written request and make two oral requests at least 15 days apart to be eligible for the drug.

The bill was inspired by the plight of Brittany Maynard, a California resident who was diagnosed in January of 2014 with a deadly brain tumor. Surgery to remove it failed, and she was given six months to live. At the time, only three states (Washington, Oregon, and Vermont) had laws that allowed physicians to prescribe life-ending drugs to such patients; two other states (Montana and New Mexico) allow it based on previous cases. So Ms. Maynard moved to Oregon where, when she judged the time was right, she died on November 1, 2014. Before her death Brittany campaigned for Death With Dignity laws, including in her original home state of California. The campaign is still ongoing after death (visit her website, thebrittanyfund.org). At least 15 states are now considering such laws.

Death with dignity laws are not for everyone. They are specifically designed to allow terminally ill patients some control over the process of their own death. They are NOT for just any old person who says they are done with life. Interestingly, even among terminally ill patients who are prescribed life-ending drugs, only about half ever actually use them. Simply having the choice seems to bring a measure of peace to some patients.

California Governor Jerry Brown has not said whether or not he will sign the bill, the final step in making it law.

A Different Kind of GMO

Here's an idea; instead of genetically modifying food plants so that they're resistant to insects, why not genetically modify the insect pests so that they can't reproduce? Perhaps that would be more palatable to people who are concerned about eating GMOs.

You've probably never even heard of a diamondback moth, and why should you have?  It's an unloved pest of cabbage patches; an invasive species that is hard to kill.  Back in the 1940s it became the first insect pest to develop resistance to DDT, a pesticide now banned.  It even resisted a technique that works with some insects - irradiation to sterilize male insects.  These days, cabbage, kale, and broccoli farmers have to spray multiple different pesticides in a single season just to keep it in check, at an annual cost of about 5 billion dollars.

But now a solution may be on the horizon: Researchers at Cornell University in upstate New York have developed a technique for genetically modifying diamondback moths so that the female larvae all die before reaching maturity.  The genetically modified moths have not yet been released into the field, and probably won't until at least 2016.  First the moths will be tested in enclosed outdoor cages to see how well they normal moths.  And of course there are regulatory hurdles to overcome.

Understandably, people who categorically oppose all GMOs oppose this one as well.  But this GMO does have some features that might make it more acceptable, according to a New York Times article. 1) It is not a human food.  2) It doesn't stray far from where it was born (or released).  3) Even if it did stray, it would be killed by the harsh New York winters, the same as adult normal moths.  4) It does not violate the rules of organic farming, so it wouldn't matter if it strayed into an organic farm field.  5) And finally, thanks to another genetic modification, the genetically modified moth glows red under ultraviolet light, making it easily identifiable from a normal moth.

It'll be interesting to see if this GMO is ever approved for use in open farm fields.   

How Did the FDA Determine the "Daily Value" for Added Sugars?

Last month I posted a blog about the FDA's new proposed changes to food labels on processed foods (see this blog Aug. 2, 2015). One of the most controversial changes was the one that defined for the first time what should be the maximum daily consumption of "added sugar" per day. Those are the so-called empty calories of sugars that food producers add to processed foods and soft drinks solely to get you to buy more of them. The FDA says that the maximum daily consumption of added sugars, which they call the "daily value" (DV), should be no more than 200 calories (50 grams) per day - the amount in just a single 16-oz soda.

Since then several people have asked me: How did the FDA come up with that number? The answer is that the FDA is relying on the Scientific Report of the 2015 Dietary Guidelines Advisory Committee, a governmental panel of scientists charged with reviewing the available scientific research and making recommendations regarding a healthy diet. The Committee found that high intakes of added sugars are associated with increased risks of heart disease, obesity, and type 2 diabetes, and concluded that "strong evidence supports reducing added sugars intake to reduce health risks."

The FDA says that according to the available scientific evidence, "it is difficult to meet nutrient needs while staying within caloric requirements if one exceeds 10% of total calories from added sugar." The FDA already uses a figure of 2,000 calories per day as the standard daily caloric intake; multiplying by 10% yields a figure of no more than 200 calories should come from added sugar.

By the way, the FDA says that the government "has no specific recommendation for added sugars"; that it is only providing the information to help consumers make informed choices. Really? A maximum daily value of no more than 200 calories doesn't sound like a "recommendation" to you?

Bracelets as Vaccine Reminders

Childhood vaccinations save lives. But vaccine schedules are fairly complex; how is a young uneducated mother in a poor country to remember when to bring her baby back for the next required vaccination? How, even, is the health care worker to know, in places where health care records are not well-kept?

Here's a clever idea; a simple flexible silicon bracelet that can be attached to the child's ankle. The idea came to Lauren Braun, a former Cornell University premedical student, while she was working in Peru one summer. Numbers on the bracelet represent the months when a mother should bring her child back for a vaccination, and symbols represent the various vaccinations needed. When a vaccination is completed the nurse punches out a symbol on the bracelet. And when all symbols are punched out, the child is fully vaccinated and the bracelet is removed. The bracelet costs about 10 cents.

Lauren has tested her idea on more than a hundred children in Peru and says that mothers and nurses seemed to find the bracelets useful. Recently her non-profit organization Alma Sana Inc. raised money through a crowd-funding campaign to fund a controlled study of thousands of mothers and infants in several countries, to prove to the medical community that the idea works. As the Alma Sana website says, "Together lets vaccinate all of the world's children".

It's often the simplest ideas that work best. Way to go, Lauren.

Treatment of Ductile Carcinoma in situ

Ductile carcinoma in situ (DCIS), also called stage 0 breast cancer, is diagnosed in about 60,000 women every year.  As the name implies, DCIS consists of abnormal cells located in the milk ducts.  In situ - "in its original place" - means that it has not metastasized. Indeed, DCIS may never metastasize.   But cancer is a scary word, and so the natural tendency is to treat all cancers aggressively, just to be on the safe side.  As a result, tens of thousands women who are diagnosed with DCIS each year are choosing to undergo treatments ranging from lumpectomies followed by chemotherapy, to bilateral breast removals.

A study published this month in JAMA oncology suggests that aggressive treatment of DCIS may not be necessary.  The authors of the study examined the medical records of over 100,000 women who had been diagnosed with DCIS.  They found that women who had been diagnosed with DCIS had about the same risk of death from breast cancer in the next 20 years as women in the general population.  In addition, they found that treatment of DCIS with either lumpectomy/chemotherapy or breast removal (mastectomy) did not alter the subsequent death rate from breast cancer.   In other words, treatment of DCIS did not appear to improve the women's survival rate, compared to the general population of women.

The JAMA oncology study is based solely on an examination of medical records, and while it raises an interesting question (Does DCIS need to be treated?), it does not answer it convincingly.  What is needed now is a carefully controlled study in which women diagnosed with DCIS are randomly assigned to either treatment (lumpectomy/chemotherapy or mastectomy) groups or to a control group, and then followed for the rest of their lives.  Such a study would be expensive and take decades.  In the meantime, the choice of how aggressively to treat DCIS, if at all, will continue to rest with the woman diagnosed with DCIS and her physician.

Developing Vaccines Against Rare Contagious Diseases

This month scientists announced that they now had a safe and effective vaccine against Ebola, the virus that caused a deadly epidemic in three African countries last year. But here's the irony; that same vaccine was shown to be effective in monkeys 10 years ago but then it was never tested fully in humans, and so it was not ready for widespread use in the latest outbreak.

How did this missed opportunity happen? Actually, it's an unintended consequence of how drugs are tested before they are approved for widespread human use. After a drug is shown to be effective (that is, it works against the intended disease or condition), it still must be tested for safety to prove that its benefits outweigh its potential harm. Testing for safety can involve thousands of subjects and can cost drug companies the better part of half a billion dollars. Drug companies are willing to undertake that expense for drugs to treat common, known conditions with lots of potential patients, such a heart disease or diabetes. But they're not willing to take the risk for a disease such as Ebola, which until the latest outbreak had been responsible for just a couple of minor outbreaks. From their perspective, what if they invested 500 million dollars in an Ebola vaccine and then there was never another Ebola outbreak?

The bottom line is that we can't expect drug companies to develop and test vaccines for rare contagious diseases on their own. Recognizing this, some scientists have suggested the creation of a global vaccine development fund of at least 2 billion dollars, to be funded jointly by contributions from governments, philanthropic agencies, and pharmaceutical companies. In all likelihood many of the vaccines might never be needed. It might sound like a waste of money to prepare for disease outbreaks that might never occur, but not compared to the total cost of another outbreak such as Ebola.

Contraceptives Reduce the Risk of Uterine Cancer Later in Life

Endometrial (uterine) cancer currently ranks as the 10th deadliest cancer, killing nearly 8,000 women every year in the United States.  It's been known for some time that oral contraceptives reduce the risk of endometrial cancer.  But women tend to take oral contraceptives only for a short period of their life when they are relatively young, and endometrial cancer is not common in younger women.  Is there any protective effect of prior contraceptive use against the development of endometrial cancer later in life, when women are no longer using using oral contraceptives?

To find out, researchers combined the data from 36 previous studies comprising over 27,000 women who had developed endometrial cancer (cancer patients), and nearly 116,000 women who remained healthy (controls).  The median age of cancer diagnosis among the cancer patients was 63 years, generally well after contraceptive use had stopped.   Just over a third of the cancer patients had used oral contraceptives; the median length of use was just three years.

The results of the study showed a clear association between oral contraceptive use and the risk of endometrial cancer later in life.  Greater protection was associated with longer contraceptive use. Overall, women who had used oral contraceptives were 31% less likely to develop endometrial cancer than women who had never used oral contraceptives. The authors estimate that in developed countries, oral contraceptive use has prevented over 200,000 cases of endometrial cancer in just the past decade.

Of course the primary reason for using oral contraceptives is to prevent an unplanned pregnancy.   A long-term reduced risk of endometrial cancer appears to be a very real secondary benefit, however. Although one might suspect that other hormonal methods of birth control such as hormonal implants might also reduce the risk of endometrial cancer, that has not yet been determined.

Should Kidney Donors be Compensated?

Is it time to seriously consider whether kidney donors should be paid? The idea has always been dismissed out of ethical concerns, but as the need for kidneys and the cost of caring of patients on dialysis continues to rise, opinions are beginning to change. Did you know, for example, that the cost of caring for patients on dialysis now consumes 7% of the entire Medicare budget? Are you aware that some countries DO now compensate kidney donors in one form or another, without any obvious negative consequences?

For an interesting and informative take on this issue, read the well-documented opinion piece in The New York Times by Tina Rosenberg. She covers the subject much better than I could here.

Updating Processed Food Labels

The FDA has proposed updating the labels that describe the content and nutritional values of processed foods. The new labels will require that serving sizes more realistically describe how much of the food a person actually eats or drinks. In the past, manufacturers could list total calories on the basis of serving sizes as small as 1/2 cup of ice cream or just 8 oz of a soft drink, for example. On the new labels, 12-, 16-, and even 20-oz bottles of soft drinks will all all be called single servings, reflecting the amount a person who purchases these sizes typically consumes at a single sitting.

The FDA proposes that the new labels list "added sugars" - sugars not part of the food naturally, but added during food processing - as a subset of total sugar. Added sugars such as refined sugar and corn syrup are sometimes called empty calories because they have no nutritional value other than calories. Food producers love them because they're cheap ingredients and because they tempt us to buy more of the product. According to the FDA, over-consumption of empty calories is contributing to the current epidemic of obesity and increases the risk of heart disease and type 2 diabetes.

Controversially, the FDA recommends that no more than 10% of a person's daily caloric intake per day should come from added sugars. Based on a typical daily caloric intake of 2,000 calories, that means that a person's total daily consumption of added sugar should be less than 200 calories (50 grams) - the amount in a single 16-oz. soda. The new food labels would require that processed foods list the percent daily value (%DV) of added sugar in a single serving, based on a 2,000-calorie daily diet.

The food processing industry is not happy about the proposed changes, for it will probably mean that the consumer will become increasingly aware of just how much added sugar there is in processed foods. Whether it'll help us cut back is anybody's guess. We'll know the new labels are working when food processors begin producing and promoting some products as having "1/3 less added sugar", like they did with fat when fat was a bad thing.

An Inhalable Vaccine Against Ebola?

A recent research study published in the Journal of Clinical Investigation offers hope that a vaccine against the Ebola virus (and perhaps other infectious diseases) can be delivered as an aerosol spray rather than injected. In the study, monkeys were given either an aerosolized vaccine against Ebola via the respiratory tract; the same vaccine in injected liquid form; or no vaccine at all. Four weeks later, all of the monkeys were deliberately exposed to the Ebola virus to see what would happen. The non-vaccinated monkeys died, whereas all of the treated monkeys survived.

At the end of the experiment the vaccinated animals were euthanized and blood and tissue samples were taken for analysis. Antibody titers against the Ebola virus were high in all of the vaccinated animals regardless of route of vaccine delivery, and there were no signs of the Ebola virus. But in addition, the animals that had received the aerosolized vaccine had developed an especially vigorous immune cell response in the lungs. This latter finding is important, because the Ebola virus may infect some of its victims via droplets of aerosolized fluids that enter the lungs. The finding of an enhanced immune cell response in the lungs suggests that an aerosolized vaccine might offer an extra level of protection against Ebola.

But perhaps the biggest advantage of an aerosolized vaccine is that it could be delivered without the assistance of medical personnel. This would be a huge advantage in places such as West Africa (where the recent outbreak of Ebola occurred) because medical personnel are scarce in that region.

An aerosolized vaccine against Ebola has never been tried in humans. Clinical trials in humans will be needed before such a vaccine would become widely available.

Replacing a Heart Valve Without Major Surgery

Replacing a failing aortic heart valve is actually pretty routine. However, the normal procedure requires cracking the chest, stopping the heart, and cutting into the heart to get to the damaged valve. Because of the traumatic nature of the surgery itself, full recovery is more likely if the patient is relatively young and healthy except for the needed valve. As a result, the surgery is not recommended for patients over about 80 years of age.

Now those older patients have a viable option. Federal regulators recently approved a new technique called TAVR (transcatheter aortic valve replacement) for replacing aortic heart valves in patients who are deemed at high risk from open-heart surgery. In TAVR, surgeons attach a folded-up artificial valve to a catheter, insert it into a main artery and thread it up to the heart, and then open it like an umbrella. The catheter lodges in place, pushing the old damaged valve out of the way. The procedure can be done in minutes with the patient awake and only lightly sedated. Recovery time is minimal.

The TAVR technique is likely to be a lifesaver for the estimated 100,000 patients who are too old or sick for open-heart surgery. One patient it has helped is former Secretary of State Henry Kissinger, age 92. Right now TAVR is only recommended for older and sicker patients because there are only 5 years of data on how long the new valves will last. But if you're 80 and need an aortic valve replacement just to get through the next year, do you really care whether the valve lasts 20-30 years?

Some surgeons think that TAVR will eventually replace open-heart surgery as the method of choice for younger patients as well. That will depend on how long valves replaced by the TAVR procedure last. It matters to someone who is closer to age 50 than 80.

Producing Omega-3 Oils in GM Plants

Aside from tasting good, oily fish such as salmon are good for you because they contain special types of fish oils - called omega-3 oils - that are known to reduce the risk of heart disease by reducing the risk of atherosclerosis. However, salmon do not actually make the oils. Omega-3 oils are made by single-celled algae, which are eaten by small herbivorous fish, which are in turn eaten by small carnivorous fish and so on up the food chain. Eventually the omega-3 oils end up in the salmon.

The demand for wild-caught salmon is leading to a depletion of salmon stocks worldwide. An alternative choice food choice would be farmed salmon, raised in enclosed bays or in pens in the oceans. Increased consumption of farmed salmon could reduce the demand for wild-caught salmon and thus prevent wild salmon from being overfished. Unfortunately, farmed salmon contain lesser quantities of omega-3 oils unless they are fed a steady diet of small fish such as wild-caught anchovies. That leads to a problem; feeding farmed fish wild-caught fish to boost their omega-3 content may just lead to overfishing of those other smaller species. And from the fish farmer's point of view, feeding farmed salmon a diet of wild-caught fish is expensive.

A solution may be on the horizon, but not everyone is going to like it because it involves genetic engineering and the creation of genetically modified organisms (GMOs). A team of scientists in England has managed to genetically modify an oil-producing plant related to rape (the plant that produces canola oil) so that it produces high yields of omega-3 oils. The new GM plant contains genes from several other plant species, including a moss and an alga. It produces enough omega-3 oils that farmed salmon could be raised on a diet of GM fish chow.

So here's the dilemma; do we want to raise farmed salmon on GM chow, producing a healthy food alternative to wild salmon and reducing the fishing pressure on wild salmon populations? Or do we want to continue to shun GMOs and deplete the world's oceans of fish?

Sometimes our choices are not all that easy.

The FDA Bans Trans Fats

Last month the U.S. Food and Drug Administration (FDA) issued a ruling that will effectively ban artificial trans fats from processed foods. The agency estimates that the move will reduce the incidence of coronary heart disease and reduce the number of heart attacks per year.

Artificial trans fats are created when vegetable oils are partially hydrogenated to create a butter-like solid. They became popular in the 1940s and '50s because they improve the texture, taste, and shelf life of processed foods and because they are cheaper than butter. However, we now know that trans fats contribute to the risk for coronary artery disease, just as the saturated fats in butter and animal fat do. The use of trans fats for deep-frying was banned some time ago, and most processed food products have already phased trans fats out. The current ruling will end the use of trans fats altogether in three years. The three-year phase-out period is to give processed foods manufacturers time to reformulate their recipes and modify their manufacturing processes accordingly.

There are small amounts of natural trans fats in beef, lamb, and full-fat dairy products such as butter and cream, but there's not much the FDA can do about that. The FDA ban only applies to trans fats added to processed foods, where the solution is to simply not use them as ingredients.

California Passes Strict Child Vaccination Law

It's been a hard-fought and closely watched battle in California. But in the end, proponents of mandatory childhood vaccinations chalked up a victory over opponents of vaccinations. Last week Governor Jerry Brown signed SB 277, a bill that eliminates personal and religious beliefs as valid reasons for not having one's child vaccinated in order to attend school. Unvaccinated children can still be home-schooled of course, and the law still allows for medical exemptions for those few children who have a verifiable medical excuse for not being able to be vaccinated. But for all others, vaccinations will now be required to attend public schools.

As it moved through the legislative process, SB 277 was modified a bit from its original form in order to make it palatable to more legislators and ensure its passage. In the final approved version, children who were not vaccinated in kindergarten will not have to be vaccinated until the 7th grade, and 10th-graders who are not currently vaccinated will never need to be vaccinated. In other words, the full effect of the new law will be phased in over several years.

California joins just two other states (West Virginia and Mississippi) that currently do not allow exemptions from childhood vaccinations for either religious or personal beliefs. Currently, 47 states allow exemptions because of religious beliefs, and 20 states allow exemptions for personal, moral, or other reasons. However, a number of states are planning to make changes to their current laws. To view the situation in your state and to find out what legislative changes might be planned or in process, visit the page on that topic on the website of the National Conference of State Legislatures.

A Libido Pill for Women?

Move over, Viagra and Cialis. Women are about to get a sexual satisfaction pill of their own. The only thing is, does it work?

Flibanserin is not a hormone-type drug; it is a neuromodulator that alters certain neurotransmitter pathways in the brain. Specifically, it is a 5-hydroxytryptamine receptor agonist/antagonist. The FDA twice rejected the manufacturer's application for approval, but now seems poised to approve it to treat two little known disorders in women; hypoactive sexual desire disorder (HSDD) and female sexual interest/arousal disorder (FSIAD).

Supposedly, Flibanserin affects a woman's sense of pleasure during sex, but a close reading of the FDA report on effectiveness is not very encouraging. In the study, half of the women received Flibanserin and the other half received a placebo. Women receiving Flibanserin reported just 0.5 to 1 more "satisfying sexual events" per month than the placebo group, from a baseline of 2-3 per month. Will that be enough for women to want to use this pill?

If Flibanserin is approved, the marketing campaign will probably focus on convincing women and their doctors that HSDD and FSIAD are far more prevalent than we think. At least, that has been the pattern with Viagra and Cialis for the treatment of erectile dysfunction (ED) in men. The latest pitch I heard is that half of all men over 40 suffer from some symptoms of ED. That sounds like a stretch....

You can read the entire 136-page FDA briefing document on Flibanserin here.

Neanderthals Interbred with Modern Humans

What happened to the Neanderthals, that now-extinct group of stocky, big-boned ancient humans who lived in Europe and Asia until about 30,000 years ago? Were they wiped out by conflict with modern humans who arrived later in Europe or by some other unfavorable environmental condition? Did they interbreed with modern humans, ultimately "disappearing" as a distinct group because their genes were incorporated into a much larger gene pool of modern humans?

Several years ago I reported (this blog May 12, 2010) that Neanderthals shared a number of genetic variations with modern Europeans that they did not share with modern Africans. These findings at least suggested, but did not prove, that interbreeding occurred when Neanderthals met modern humans.

More recently, DNA analysis reveals that up to 3% of the DNA of modern Eurasians is similar to the DNA of the Neanderthals. And according to a paper published this week in Nature, DNA analysis of a bone of a modern human who lived in present-day Romania around 40,000 years ago revealed that 6-9% of his genes were from Neanderthals. In other words, he may have had a great, great-grandparent who was a Neanderthal.

Of course, this does not prove that interbreeding was the cause of the disappearance of the Neanderthals. Interbreeding can occur between groups in conflict, as the behavior of modern-day humans clearly shows. But at least it indicates that interbreeding did occur, at least occasionally.

Breast-Feeding Correlates with Reduced Risk of Leukemia

Yet another reason to consider breast-feeding your baby; a study just published in JAMA Pediatrics reports that children who are breast-fed for at least 6 months have a 19% lower risk of developing childhood leukemia compared to children who are not breast fed at all. Childhood leukemia, a type of blood cancer, is a leading cause of death among children and adolescents.

Scientists have long known that breast milk contains antibodies and immune-strengthening compounds that help support the infant's immature immune system. The American Academy of Pediatrics recommends that women breast-feed their infants because it lowers the risk of infections and allergies, among other known benefits. But this is the first time that a correlation between breast-feeding and reduced risk of leukemia has been documented.

Of course, the finding of a correlation between breast-feeding and reduced leukemia risk does not prove that it is actually breast-feeding (or breast mik) that lowers the risk of leukemia. Remember, a correlation does not prove cause and effect. It could be something else entirely. It does fit, though, with what we know about breast milk and the role of the immune system in recognizing and destroying abnormal (cancerous) cells.

Perhaps some day we'll know for sure if indeed breast milk lowers leukemia risk. But for now, the study's authors can only conclude that breast-feeding may lower the risk of childhood leukemia.

Still No Known Benefits From Eating Placenta

Eight years ago I reported on what was then a relatively new phenomenon - eating one's own placenta (see this blog July 19, 2007.) I pointed out that the reported health benefits of this practice were based on anecdotal reports, meaning that they were scientifically untested. My hope was that some day someone would look into this phenomenon and be able to tell us whether it is just a fad or whether there really is something to it.

Flash forward to the present day. A recent search of the scientific literature on the subject found 49 papers, only 10 of which were deemed of sufficient quality to be included in the final analysis. None of the 10 papers offered conclusive evidence of a health benefit of eating the placenta. The bottom line is that eight years on, there is still no good evidence that eating the placenta after birth has any health benefits at all.

According to the study's authors, the health benefits and risks of eating the placenta "require further investigation." But at this point I'm wondering, why bother - why not just refrain from eating placenta in the first place? Problem solved.

GMOs; the Fear is Not Backed by Good Science

It's trendy these days for food companies and even restaurants to label their foods as free of GMOs (genetically modified organisms) wherever possible. Some states are passing laws requiring that all foods containing GMOs be labeled as such. It's happening not because there is good science to show that GMOs are bad, but because there is a perception that they are bad. According to a recent article in The New York Times, the antipathy toward GMOs "reflects a poor public understanding of the science behind them, along with a rebellion against the dominance of food and agricultural conglomerates."

The article goes on to list some of the facts about genetic modification and genetic engineering, and then points out some of the successes of the technique, including a rice that produces the precursor to vitamin A which could significantly reduce blindness in some countries. But then the article suggests something new; perhaps genetic engineering could be used to remove specific naturally-occurring genes from certain foods, such as peanuts or shellfish, that cause serious life-threatening allergies in some people. By the way, no GMO food has ever been proven to cause a life-threatening allergy.

It's unfortunate that the first two major GMOs were corn and soybeans that were genetically engineered to be resistant to insect pests or to a commonly-used herbicide - both of which primarily benefit large agricultural seed companies and big farmers. Would there still be objections to GMOs if the very first ones had prevented certain nutritional deficiency diseases or severe food allergies? I wonder.

I'm not necessarily in favor of some mega-farm farming practices or of the unnamed seed company that has a near lock on the GMO seed market, either. But these are a whole different set of issues from the safety of GMO foods. 

GINA Applies to DNA Tests for Identification Purposes

The police can use DNA tests to identify suspects, but apparently, private companies cannot, according to a recent court case. The company that wanted to identify the "devious defecator", an employee who was defecating regularly in its warehouse. To solve the mystery the company asked several employees for samples for DNA testing. The employees were cleared, but they later sued the company.

Last month a federal court in Atlanta ruled in favor of the employees, ruling that a DNA test of an employee by a private company violates the Genetic Information Nondiscrimination Act (GINA). As you may recall, GINA protects employees from employment discrimination by making it illegal "for an employer to request, require, or purchase genetic information with respect to an employee." In its decision, the court ruled that although in this case the employees' DNA samples were not used to test for specific genes, they could have been used for that purpose and hence the mere act of asking the employees for a DNA sample violates GINA.

It's a surprisingly narrow interpretation of GINA, especially since GINA does not protect you against discrimination in other areas, such as life, disability, and long-term insurance (see this blog Apr. 17, 2014.) It will be interesting to see if this interpretation holds up in future cases.

Beta-Amyloid Accumulation Precedes Alzheimer Disease

In patients with Alzheimer disease, the most common cause of dementia, deposits of an abnormal protein called beta-amyloid accumulate around neurons in the brain. It is thought that these beta-amyloid deposits choke off neurons, eventually killing them. When there are too few neurons left, cognitive impairment and eventually dementia set in. But when exactly do these beta-amyloid deposits begin to accumulate, and could their accumulation and the subsequent development of Alzheimer disease be prevented? Attempts to find drugs that would prevent the development of Alzheimer disease have been hampered by the fact that it is difficult to find people to test the drugs on; that is, people who are still seemingly normal but who are likely to develop Alzheimer disease later in life. By the time Alzheimer disease becomes evident, it's too late to prevent it; all one can do is treat the symptoms.

Now a new study offers hope. It's a meta-analysis (remember, a meta-analysis is a study of previous study; like a summary) of 55 previous studies, involving over 7,500 persons who were either normal or had subjective or mild cognitive impairment - none had reached the level of Alzheimer disease yet. All of the studies looked at the prevalence of beta-amyloid pathology, either by positron emission tomography (PET) scan or by analysis of cerebrospinal fluid.

The study found that the prevalence of beta-amyloid pathology increased with age and decreasing level of cognitive function, ranging from 10% in 50-yr-olds with normal cognition to over 70% in 90-yr-olds with mild cognitive impairment.

Most importantly, the study suggests that beta-amyloid pathology begins to develop as early as 20 to 30 years before the onset of dementia. This is good news for researchers seeking to find a drug to prevent Alzheimer disease. By testing a lot of seemingly normal individuals and then enrolling only persons with evidence of beta-amyloid pathology (persons at high risk for Alzheimer disease) in their research studies, the researchers are more likely to find a potential Alzheimer prevention drug that works.

For those of us unlikely to enroll in a research study, however, it's not a particularly helpful finding. Yes, we could be tested to see if we had signs of beta-amyloid accumulation yet, but what would be the point, if there is no cure?

A Drug Company is Forced to Keep a Drug on the Market

I've often wondered why some people seem to have such a negative impression of the big pharmaceutical companies that develop and market the medical drugs we all need and use. Well, once in awhile a company does something so egregious that it's hard not to side with the pharma-haters.

Take the recent actions of Actavis, the pharmaceutical company that makes a top-selling drug for the treatment of Alzheimer disease called Namenda IR. Namenda IR goes off patent this September; after that, stiff competition from generic drugmakers would have made the drug much cheaper. But Actavis has developed a new, longer-acting formulation called Namenda XR that is under a new patent. So last year the company announced that it would discontinue the old drug, well before its patent expired. Why? By discontinuing the old drug, the company would force users to switch to the newer (more expensive) drug and get them used to taking it before any generic drug could become available! By the way, the active ingredient in the two drugs is exactly the same; the only difference is that the new drug needs to be taken only once a day instead of twice a day for the old drug.

Inquiring minds saw through that one. The State Attorney General of New York sued Actavis, arguing that Actavis was trying to stifle competition from the generic drug industry (duh!), and thus was violating state and U.S. antitrust laws. And last week a Federal Appeals court in New York ruled that Actavis must continue to keep the old drug on the market, according to an article in The New York Times.

Actavis got caught this time. But this sort of shenanigan happens all too often.

Grip Strength and Cardiovascular Disease Risk

An interesting new study published in The Lancet adds additional evidence to the hypothesis that reduced muscular strength is associated with an increased risk of cardiovascular disease. The study determined the grip strength of nearly 140,000 men between the ages of 35 and 70 years, in 17 countries. Then they followed them for a median of four years, during which time 3,379 of the men (2%) died.

After controlling for other variables such as age, there was a positive association between grip strength and death from cardiovascular disease, including both myocardial infarction (heart attack) and stroke. Specifically, every 11-lb reduction in grip strength was associated with a 17% increase in death from cardiovascular disease. Grip strength was even a stronger predictor of death from cardiovascular disease than was systolic blood pressure. There was no association between grip strength and the risks of diabetes, hospital admissions for respiratory disease, or accidents.

The authors suggest that grip strength may be a simple, inexpensive, and quick way to categorize (in very general terms) a person's risk of death from cardiovascular disease. But don't read too much into this. An association between grip strength and risk of cardiovascular disease does not mean that reduced grip strength is the cause of the increased cardiovascular risk. It's just a useful predictive tool, nothing more.

Chinese Scientists Genetically Modify Human Embryos

Well, we knew it was bound to happen sooner or later, regardless of whether people think it's a good idea. Chinese scientists tried recently to modify the genes of human embryos. It was just an experiment and it didn't work this time, but who's to stop them or someone else from trying again? Had they been successful, the genetic modifications could have been passed on from generation to generation.

In their experiment, the Chinese researchers used 85 human embryos left over from in vitro fertilization techniques. Using an advanced DNA editing technique called CRISPR, they tried to cut out a gene and insert another in its place. All 85 attempts failed. In nearly every case either the gene was not edited properly or the embryo died.

The ultimate goal of being able to modify a human's genome would be to be able to eradicate certain human genetic diseases. But a lot of people are squeamish about trying to modify the genes of humans. Aside from the obvious risk of something going wrong (as it did with all 85 of the attempts by the Chinese scientists), what's to stop the technique from being used for all sorts of other modifications of the human genome, beyond just eradicating certain diseases? Most scientists are not convinced the technique should ever be used, even if it seems to be likely that it could be done successfully. But almost for certain, others will try. The time to start thinking about it is now, not after someone actually does successfully modify a the genes in a human embryo.

The paper by the Chinese scientists is difficult to read, but here it is if you'd like to try. More about the CRISPR technique can be found here.

Type 2 Diabetes and Sweetened Drinks

We've all heard that type 2 diabetes is on the rise, and that one of the suspected reasons is the number of sweetened drinks we consume these days. But how many is too many, and would it do any good to cut back?

A new British study offers a tantalizing clue, although it's a bit of a "soft" study because it relies only on self-reports of dietary consumption. The study asked over 25,000 British adults about their consumption of sweetened and unsweetened drinks of all kinds, and then tracked their development of type 2 diabetes over 11 years. After adjusting for obesity, and the results showed that reducing consumption of sweetened drinks to less than 2% of total caloric intake could reduce the incidence of diabetes by 15%.

That's fine, but I certainly wouldn't know what 2% of my total caloric intake per day is, in terms of number of sweetened drinks. So how about this? Substituting just one serving/day of water or unsweetened tea/coffee for a sweetened drink was associated with a 14-25% reduction in the incidence of diabetes. Just one serving.

It's something to think about.

Global Warming and Moderate Weather Events

The evidence continues to accumulate that global warming will lead to climate change; specifically, that extreme weather events will become more common. And now there's yet more evidence. The authors of a recent paper looked at past incidences of more moderate events, such as daily heat waves and precipitation events large enough to occur once every three years. Then, using a climate model, they predicted the number of such events in the future depending on the extent of global warming.

According to their model, so far global warming hasn't had much of an effect on moderate precipitation events. However, if global warming increases to 2o C we can expect the number of moderately heavy precipitation events to increase by about 65%.

The effect of global warming on moderate heat waves, however, is much worse. Already, the 0.85o C rise in global temperatures since pre-industrial times has increased the number of moderately hot days by about 5-fold. If global warming rises to 2o C we can expect another 5-fold increase in hot days.

Of course, predictions about the future are based on climate models; models that are developed based on past experience. Predictions may or may not come to pass. But climate models are getting better every year; we ignore them at our peril.

Global warming, climate change, and species extinctions

In the latest study of the effect that global warming and climate change may have on species extinctions, a study from the University of Connecticut concludes that up to one in six species may be at risk of extinction, depending in the amount of global warming that actually occurs. The study is what is called a meta-analysis; it combined and summarized the data from all of the available global warming -species extinction studies available that met certain criteria of relevance and quality - 131 studies in all.

The results of the study suggest that only 5% of species would become extinct if global warming could be kept to the international agreed-upon target of just 2 degrees centigrade above pre-industrial levels. But virtually no one believes now that we can keep global warming to that limit, given our failure to curb global warming so far. Many of the individual studies summarized in the present meta-analysis predict global warming of more than 4 degrees centigrade, leading to the higher estimate of 1 in 6 species at risk of extinction (about 16%). Most of the extinctions will occur in the tropics, according to the analysis.

Current climate change models predict only what might happen in the time period of decades or centuries. Extinctions might be much higher if higher global temperatures were to persist for tens of thousands of years. Indeed, some scientists think we may be entering a prolonged period that will become the sixth mass extinction experienced by Earth over its 4 billion life span so far.

Many species are likely to be affected by global warming and climate change, even if they do not become extinct. Species may undergo substantial changes in populations, range, and interactions with other species, for example. The good news is that over prolonged periods of time (thousands to millions of years), evolution will continue and species will adapt and change. Life will go on, though whether humans will still be here is anybody's guess.

A Former Anti-GMO Activist Becomes a GMO Supporter

A former campaigner against genetically modified organisms (GMOs) now says that he supports GMOs. Dr. Mark Lynas, a researcher at the Cornell Alliance for Science who by his own admission once participated in vandalizing field trials of GMO plants in Europe, writes that he feels compelled to reverse his position after coming to the conclusion that GMOs are completely safe to eat and that they offer benefits to society in terms of food security and environmental protection. But don't just believe me; read what he has to say, in his own words.

The FTC Sues Two Marketers of Melanoma Detection Apps

The Federal Trade Commission (FTC), the federal agency whose mission is to protect consumers from misleading or false advertising, filed a lawsuit and reached a settlement with the marketers of two smartphone apps who claimed that their apps could calculate the risk of a mole being a melanoma. According to the FTC, that's akin to offering medical advice. According to the FTC, the companies cannot offer medical advice "unless the representation is truthful, not misleading, and supported by competent and reliable scientific evidence in the form of human clinical testing" of the device.

This raises an interesting question. Who (which government agency) is responsible for oversight of cellphone apps that appear to cross the line by offering medical advice? Are cellphone apps communication devices that should be regulated by the FTC (as was done in this case), or in a health-related context should they be called medical devices, and therefore regulated by the Food and Drug Administration (FDA)? At the moment no federal regulatory agency is clearly responsible, and so the first apps have gone largely unregulated. Until the FTC stepped in, that is.

California Legislature Debates Vaccination Bill

The California legislature is considering a bill that would prevent parents from seeking exemptions from vaccinations for their children on the basis of personal beliefs. SB 277 would also require school boards to provide notifications to parents each year of the vaccination rates at their child's school, presumably so that parents could make informed choices about keeping their child out of school during a disease outbreak.

Public hearings on SB 277 were held this week in the Senate Education Committee. Supporters of the bill raised concerns for their children's health in the wake of the recent outbreak of measles in California. They want all children to either be vaccinated or kept out of school during disease outbreaks. Opponents of the bill say it infringes on their personal rights not to vaccinate their children, and that there was no significant public health crisis posed by the few cases of measles which occurred during the most recent outbreak.

Let's hope this bill passes.

Is Most of Your DNA Junk?

When scientists first sequenced DNA and began to identify what it was doing, it became apparent that there was a lot of DNA that was not part of any gene, that is, it didn't seem to code for anything. That led to the view, first popularized in the 1970s, that nearly 99% of your DNA was just junk.

But more recently, we've learned a lot more about some of those non-coding regions of DNA. Although they don't specifically code for proteins, there is now evidence that at least some of the non-coding regions seem to be important in turning genes on and off, and thus they may be important in directing the timing of development, among other things. That has led to the currently popular view that there is no junk DNA. At scientific meetings, the discussion sometimes gets a little heated.

But does the finding that some non-coding DNA is useful necessarily mean that there isn't a lot of junk? It's hard to imagine that cells are so efficient that they have managed to eliminate all junk from DNA when it occurs. If a junk sequence did no harm, what would cause it to be selected against during the course of evolution? In all likelihood it would just remain there forever. And that's exactly what "junk DNA" proponents believe.

And so the debate rages on. Before you decide where you stand on the junk vs. no-junk debate going on in biology today, read the fairly well-balanced article in the New York Times.

A Polio-Like Disease is Linked to an Enterovirus

Remember that outbreak in California a year ago of polio-like symptoms in more than 20 children? (See this blog Feb. 28, 2014.) It now appears that it is linked to a strain of enterovirus called EV-D68 that first appeared in California in1962.

Enteroviruses are a genus of single-stranded RNA viruses. The best-known enterovirus is the one that causes polio, but there are about 100 strains of non-polio enteroviruses as well; EV-D68 is one of them. Enteroviruses generally enter their victims via the respiratory system, producing primarily flu-like symptoms. But in some patients, EV-68 appears to migrate to the nervous system, where it causes partial or full paralysis of one or more limbs. The nervous system damage caused by EV-68 is not always reversible, and many of the children infected last year still have symptoms of paralysis from their infections.

So, we now know the cause. That's the first step; now we need a cure.

Wearable Smart Devices and Medical Monitoring

The advent of the Apple iWatch and other devices like it are likely to create all kinds of opportunities for monitoring the wearer's health. But in addition the combined data from these devices, if it could be made available to researchers, might take our understanding of certain diseases to a whole new level.

 Last week Apple announced the availability of a suite of software called ResearchKit that is supposed to make it easy to create apps that work with its mobile devices, including the iWatch. ResearchKit is "open source", meaning that anyone can use it to design data-collecting apps. Interesting apps currently available include GlucoSuccess, developed to help diabetics track their activity and keep track of their food intake; Asthma Health, to track asthmatic symptoms; and mPower, designed to track symptoms of Parkinson's disease. Other apps have been developed to monitor and record heart rate and levels of physical activity.

Each of these apps provides useful information to the individual who is wearing the device, and thus possibly to his/her doctor as well. But in addition, the user is asked to be a "citizen guinea pig", that is, to make their personal data available to researchers. The idea is that data collected from tens of thousands of persons in real time might have real power in helping us to learn more about the medical conditions being monitored and how to treat them.

It's worth thinking about the issue of privacy carefully before one decides to participate. But the idea that one could be helping others in the future is a real attraction.

The Ebola Outbreak is Subsiding

The Ebola outbreak in Guinea, Liberia, and Sierra Leone seems to be subsiding somewhat. The number of new cases is currently running at about 100-150 per week, down sharply from the 800-1,000 cases per week in October-November of 2014. The overall death toll now stands at 10,326 out of 24,907 confirmed cases for a death rate of just over 40%, according to the World Health Organization. There have been only four cases (and one death) in the United States.

Several factors are contributing to the slowing of the outbreak. The virus never went airborne, to the huge relief of health officials. And it turns out that patients are most likely to infect others late in their infection, rather than early. As a result, identifying and isolating infected persons quickly and then tracking down and testing persons with whom they have been in contact has been the key to containment. Getting people to change cultural practices, such as kissing and shaking hands as greetings and washing the dead prior to burial, has slowed the spread of the disease as well.

Nevertheless, it's still too soon to declare the outbreak over. It takes a lot of manpower to find and test all the persons who may have been exposed to someone with the disease, and the three countries with the most cases lack those kinds of resources. Nearly half of all new cases are identified only post-mortem (after death), which makes containment and tracking of exposed persons more difficult.

There are still no cures or effective preventative vaccines for Ebola. Let's hope we can continue to keep this outbreak contained until cures are available.

Horizontal Gene Transfer in Humans

People who worry about genetic modification of organisms by the transfer of genes from another species should know that it happens naturally, even in humans.  The transfer of genes from one species to another in nature is called horizontal gene transfer.  It's rare, but it does happen.

What's the evidence for interspecies gene transfer?   In a paper published recently in Genome Biology, researchers at Cambridge University examined currently available genetic databases of primates (including humans), fruit flies, and nematode worms (the groups were chosen because their genetics are fairly well-known).  They then searched the world's known genetic databases for all other organisms for exact matches to specific genes within each group.  Matches within a group (e.g. all primates), are most likely to descent from a common ancestor.  On the other hand, matches between completely unrelated species (e.g. humans and bacteria), are most likely due to horizontal gene transfer at some time in evolutionary history.

The findings suggested all three groups have picked up genes from totally unrelated species over the long time course of evolution, including genes from algae, fungi, and bacteria.   Humans, for example, have picked up more than 145 genes from other species.  That's not a lot out of the 20,000 or so in the human genome, but its at least evidence that horizontal gene transfer does occur.  Most of these horizontally transferred genes in humans were acquired from bacteria early in human evolution.

Are we better off for it or not?  That remains an open question.  In terms of the current debate over the safety of genetic engineering, it's worth noting that the natural process is glacially slow compared to the modern purposeful transfer of genes.   Still, it's interesting that the process does occur in nature.

Two New GMO Foods on the Horizon

The latest entries into the genetically modified organisms (GMOs) category are an apple that resists browning when sliced or bruised, and a potato that allegedly produces less of a suspected carcinogen when deep-fried, according to news articles in the New York Times.

The apple is only a modest "improvement". Its ability to resist browning primarily benefits grower, shippers, and sellers by reducing their losses of browned fruit. Secondarily it could open the way to pre-packaged sliced apples in the store, but is that really going to be a big market?

But the potato may be a whole different story, and it may well test the public's understanding of its possible benefits versus the fear some people have of all GMOs. The genetically modified potato contains less of the amino acid, asparagine, according to Simplot, the potato's developer. When heated to very high temperatures such as deep frying, asparagine reacts with sugar to produce acrylamide, a suspected carcinogen. How much asparagine there is in a potato Simplot didn't say, but I suspect it's way less than in most meats. This sounds like making a big deal out of not very much, in an effort to gain widespread acceptance.

An understanding of the word "suspected" is key here. According to the National Cancer Institute, toxicology studies indicate that acrylamide may be a risk for certain cancers in animals, but so far there is no direct link between acrylamide and cancer in humans. There's certainly not enough evidence to ban potato chips and french fries just yet.

How will the market react to the new GMO potato? There have been news reports that McDonalds's has already said it has no current plans to use the new potato. And a genetically modified potato has been tried before; Monsanto pulled its insect-resistant potato from the market after buyers rejected it.

Oh, and by the way, the genetically modified potato does benefit growers, shippers, and retailers, too. Like the apple it resists bruising, so it would reduce annual potato waste by 400 million pounds per year, according to Simplot. I just knew there'd be something in it for Simplot.

Bacon and Eggs are Back!

Since the 1960s we've known that high blood cholesterol is a risk factor for atherosclerosis, a disease in which coronary arteries become narrowed by sticky deposits of cholesterol. And so, in an effort to try to keep blood cholesterol within healthy limits, since 1961 the government's dietary guidelines have advised us to avoid high-cholesterol foods such as (bacon and eggs).

That's about to change. In February an influential federal panel of experts that advises the secretaries of Agriculture and Health and Human Services announced that even though high cholesterol is indeed a risk for coronary artery disease, cholesterol derived from dietary sources is not really a significant health risk after all. The panel recommends that cholesterol no longer be called a "nutrient of concern" in the newest version of Dietary Guidelines for Americans, due out later this year.

How did such a complete switch come about? It turns out that the more nutritionists learned about cholesterol, the more they realized that cholesterol is actually an essential nutrient. It is a component of cell membranes, for example. Furthermore, approximately 80% of the cholesterol in your body is synthesized within the body, primarily by the liver. Because only about 20% comes from dietary intake, restricting dietary cholesterol intake is just not a very effective way to lower blood cholesterol levels.

Another significant change in the last fifty years has been the development of effective cholesterol-lowering drug such as Lipitor. Taking a cholesterol-lowering drug is a far more effective way to lower cholesterol than any change in diet.

Finally, experience has shown that when people are asked reduce their intake of one energy-rich food (saturated fats and cholesterol-rich foods, for example), they naturally tend to substitute something else, and oftentimes that something else is sugar. After all, the only three basic choices are fats, sugars, and proteins! And too much sugar isn't good for us, either.

And so once again we can include bacon and eggs in our diet, guilt-free. All things in moderation, of course.