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.

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.

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.

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?

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.

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.

Advertising for a Kidney on Craigslist.org

A 28-year-old Florida woman who desperately needed a kidney transplant made a plea last summer on Craigslist.org 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.