News about health and medicine abounds; clear guidance often doesn't. We've picked a handful of important or intriguing health stories from the last month and asked Sydney Spiesel, a pediatrician who teaches atYale University's School of Medicine, to explain and venture an opinion about them. Below are his takes on statins, weight and mortality, Mexican prescription drugs, teens and oral sex, three new vaccines, and honey as a burn treatment.
Statins: They may lower the risk of cancer. But be careful which one you take.
State of the science: Statins, drugs that lower cholesterol by blocking its production, have demonstrated their value in decreasing coronary artery disease and heart attacks since they were introduced in the United States in 1987. They've also turned out to be surprisingly good at preventing medical problems that seem unrelated to cholesterol level—for example, strokes. And now it seems that taking a statin might lower the risk of some kinds of cancer. Though the results of previous research had been mixed, a recent study looking at colorectal cancer suggests an association between taking statins and a decreased risk for this illness. It's not yet clear whether the association is causal or coincidental, but it is nonetheless intriguing, especially because another recent large study of American veterans showed similar results for prostate, breast, lung, and other cancers.
Caveat: Statins have long been known to cause a major, if rare, side effect: the death of muscle cells, which leak materials that in turn clog and damage the kidneys and other organs. This risk depends on factors including dose and patient ethnicity and age, and some statins are more likely to lead to this problem than others. One (Baycol) was taken off the market for this reason. Now Crestor, which is heavily promoted and commonly prescribed, has been shown to pose a greater risk than other statins for muscle and kidney damage.
Prognosis: Future research will clarify whether statins fulfill their promise for preventing strokes and some kinds of cancer. For now, it's clear that they help prevent heart disease, and the risks associated with them are pretty low when doctors are careful about dose and patient selection. Special care should be taken with Crestor for patients who need high doses or take other medications that increase the risk of muscle breakdown, and it's not clear that the drug has any additional benefit not found in the marginally safer statins. Oddly, Asian-Americans develop unusually high blood levels of Crestor, which might put them at higher risk for dangerous side effects.
Weight and Mortality: Is it really OK to be fat now?
State of the science: The old truism was that thinner is healthier. That conclusion was based on the 1943 Metropolitan Life Insurance tables (nicely illustrated and discussed here), which found that lower body weights were associated with lower mortality rates. But the tables were based on the company's insured population, which was probably relatively healthy and mostly white. In addition, the raw data were not collected in consistent, rigorous, or scientific ways and weren't broken down by age, which recent studies have shown influences risks related to weight. Now new studies, rigorously analyzed at the National Center for Health Statistics, are scrambling the old picture of the relationship between weight and mortality. Guidelines put out by the National Heart, Lung, and Blood Institute break people into groups according to their scores: "underweight," "normal," "overweight," and "obese," which is further subdivided into three levels of severity. The new studies also look at how the relationship between weigh body mass index t and death rate is influenced by age, gender, smoking habits, and whether a patient's excess weight was maintained over a long period of time. The results that grabbed headlines:
• At any age, being "underweight" increases the risk of dying the most.
• People classified as "overweight" are less likely to die than those of "normal" weight, even if they carried the excess weight for a long time.
• For people under 70, being moderately or very obese increased the risk of death a lot, but for the more elderly, only a little.
Caveat: When I read this study, my temptation was to reach for a second portion of cream pie. But do the findings support giving in to temptation? Sadly, not really. The new research tells us that when we look at population averages, people already in the "overweight" group are probably going to do OK, but it says nothing about whether changing one's weight in either direction is safe. The study also addresses only one outcome—death. It doesn't tell us if overweight people are more (or less) subject to illnesses or health problems that don't have lethal consequences. Also unanswered is the question whether moderate chubbiness is a surrogate for the prosperity that buys good health care, good education, leisure, and good housing, as well as good food.
Prognosis: Overweight people could live longer for lots of quality-of-life reasons that researchers haven't yet accounted for.
Mexican (Prescription) Drugs: What you get south of the border.
State of the science: Every day my e-mail box brings me the glad tidings that whatever medicine would make my heart happy is mine for the ordering. Though I know Canadian pharmacies are pretty rigid about requiring a prescription written by an actual doctor, I have understood that Mexican pharmacies are likely to be more obliging—and perhaps less reliable in what they supply. A recent warning by the FDA backs up that hunch. The report found that three drugs bought in Mexican pharmacies near the U.S. border were counterfeit: Evista (a treatment for osteoporosis), Lipitor (a cholesterol-lowering drug), and Viagra. The counterfeit medications contained few or no active ingredients and wouldn't achieve their intended purpose, which might be obvious in the case of Viagra but dangerously invisible in the case of the other two.
A better idea: The FDA's warning is somewhat helpful, and the accompanying pictures may help you figure out if you've been scammed. But I wish the FDA would give us more information so we could assess the magnitude of the counterfeiting problem. The critical questions are these: What is the real risk that a medication bought in a Mexican pharmacy is not the real thing? What percentage of drugs purchased across the border are defective? How and how often were these bad drugs found? Without more information, it's hard not to wonder if the FDA is following the agenda of big pharmaceutical companies that don't want Americans to buy discounted Canadian or Mexican drugs.
Prognosis: For now at least, it pays to be cautious about buying medications—especially expensive and popular ones—in Mexican pharmacies along the border.
Teens and Oral Sex: They're smarter than they get credit for.
State of the science: A recent paper reports, with mild disapproval, that teens are having oral sex with increasing frequency and regard it as a better choice than vaginal sex. What are the risks of oral sex, and how do they compare with the risks of vaginal sex? Here's how I'd put together the many small observational studies I've read: The risk of HIV transmission is clearly lower with oral sex, and the risk of pregnancy nil. The risk of chlamydia is much lower, as is the risk of papilloma virus (a cause of genital warts and cervical cancer). The risk of syphilis and oral and genital herpes are likely similar. The risk of gonorrhea is probably lower for oral sex but still appreciable. The teenagers did well at sussing out these relative risks, though a small number wrongly thought there is no risk from oral sex of infections like chlamydia.
Contrarythought: The authors of the paper find it a little troubling that teens are indulging in oral sex and deluding themselves that it's not really sex and that it's less risky. But if the alternative is vaginal sex—as opposed to the less likely abstinence—then the kids are quite correct about relative risk.
Vaccines: Which new ones are worth the price?
State of the science: The latest thing in pediatrics is a vaccine to prevent the meningococcal variant of bacterial meningitis. This variety of infection is especially frightening. More than half the cases in the United States are in children and young adults. Very young children and college freshman living in dorms are especially vulnerable; also at risk are travelers to central Africa, pilgrims on hajj to Mecca in Saudi Arabia, and (as of the last few weeks, when a small epidemic began) visitors to New Delhi, India. A vaccine has been available for a while, but the protection it offers is relatively brief—maybe three years—and it is ineffective in younger kids.
Prognosis: The new vaccine will almost surely provide a much longer period of protection—probably lifelong for many people—and will work fairly well even in young children. It closely resembles a similar vaccine used in England. The new vaccine is strongly recommended by most public-health authorities. On purely medical grounds, it's hard to argue with this recommendation.
Caveat: The cost per life saved by this vaccine is phenomenally high. When it was licensed, its manufacturer, Sanofi Pasteur Inc., announced that the new product would cost about the same as the older version. That's true, but only because Sanofi almost doubled the price of the older vaccine just before releasing the new one and pricing it at more than $80 a dose wholesale. It's a little hard to understand the basis for the high price, since the technology used to develop the vaccine was not new and there is nothing else to suggest that it was expensive to manufacture. Meningococcal disease is pretty rare—all told there are only about 1,750 cases a year in the United States. A recent coldblooded economic analysis that took into account the vaccine's expected financial and social benefits projected a cost between $5 million and $25 million per death averted and between $630,000 and $2 million to prevent a single case. (The wide ranges reflect the potential cost of protecting young children, who will require as many as four doses to develop good immunity.)
A better idea: The costs and benefits balance better for two other new vaccines—one for whooping cough, which has reappeared and can be deadly for infants, and the other the combination MMRV for measles, mumps, and rubella (German measles), and chickenpox. The original whooping cough vaccine, introduced in the 1930s, was too toxic to give to adults or older children. (Counterintuitively, the older you are, the more severe your likely reaction.) But the new and purer forms cause hardly any reaction in teens. Last month, the product Boostrix was licensed; it adds protection against whooping cough to the standard vaccine that teens already get to reinforce their protection against tetanus and diphtheria. MMRV, for its part, should completely replace the separate chickenpox and MMR vaccines that children now receive twice and will likely increase protection against chickenpox.
Honey: What bees know about treating burns.
State of the science: At a recent conference on wilderness medicine, I learned for the first time about a traditional burn treatment used in many native cultures: the application of honey. A body of medical research supports the practice—not only anecdotal reports, but also scientific studies documenting some of the properties that make honey a plausible treatment for burns. A common and catastrophic complication of burns is bacterial infection, and all modern methods of burn treatment make use of materials that suppress bacterial growth. Honey, too, can strongly inhibit the growth of bacteria.
The current gold-standard method of testing is whether a treatment works in a "random controlled trial," in which patients with similar problems are randomly assigned to different treatment groups and the results are compared. Seven small but good-quality studies of this kind have compared the use of honey against other treatments for mild or moderate burns. In six of them, honey produced better results than the treatments with which it was compared.
Prognosis: These are preliminary studies that need to be replicated, but so far it looks like this is a folk remedy that may work. Additional research might help identify and make use of the active ingredients in honey that seem to suppress bacterial growth and perhaps also promote healing—and might have applications beyond the treatment of burns.