Buffalo News, 08-16-05
The more medicine pushes for absolute certainty, the more it will have a distinct blind side. Putting it another way: the less we tolerate ambiguity, the more likely it is we will make structural mistakes in our thinking.
In matters of life and death, of course, we reach for certainty like a drowning person reaching for a life raft. So I wasn't surprised by an article that was brought to my attention recently summarizing the evidence on cholesterol-lowering strategies.
High LDL cholesterol, of course, is bad for you, and is one of the major risk factors for heart disease. Lowering cholesterol reduces risk of heart attacks and death.
The study was a meta-analysis -- a type of study that combines data from many other studies to generate statistics that are, it is felt, more reliable than numbers from any single study. It was published in the Archives of Internal Medicine in April.
The study compared the effects on death rates of six interventions to treat high cholesterol: the "statin" drugs like Lipitor, the "fibrates" like Tricor, resin drugs that bind cholesterol in the gut, the vitamin niacin in high doses, fish oils as supplements, and dietary changes.
What was shocking to me was that the greatest effect on reducing death rates was with fish oil supplements. Fish oil reduced death rates by 23 percent, as compared to 13 percent for the statins, zero percent for the fibrates, 16 percent for the resins, 4 percent for niacin and 3 percent for diet.
Interestingly, fish oil also had the lowest reduction in cholesterol levels -- only 2 percent -- of all the interventions, suggesting that it is helping patients through some other way than by reducing cholesterol.
Now for the skeptics, I invite you to review this article. It appears to be scientifically sound, with a large number of patients in the fish oil trials (about 10,000) and an appropriate statistical significance. Take a look at it and correct me where I'm wrong.
So much more than Lipitor, or any other cholesterol lowering drug, taking a few capsules of fish oil cuts your risk of dying of heart disease.
But why aren't we hearing about this? Why isn't this the next fad?
The short answer is economics: no company is going to make money by investing millions in marketing fish oil when other companies would benefit from the marketing, too. You can't patent smashed fish.
But there's another problem, too. It just sounds crazy. It doesn't fit in with the consensus reality of medicine. I know that if I started walking around my hospital prescribing fish oil for patients with heart problems, people would start questioning my ability to practice medicine. I really don't want to think about what would happen.
And that's the sad part. We pride ourselves on being "evidence- based," on doing for our patients only what we have scientific evidence to back up. But then we're afraid to go where the evidence leads us. A more conventional example is how the clot-busting drugs for acute heart attacks were accepted only a really long time after they were proven to work.
Back to fish oil for a minute. If you're worried about toxins, including mercury and PCBs, I would refer you to a Consumer Reports article a few years ago that found that commercially available fish oils contain no significant amounts of dangerous toxins.
I have prescribed this stuff to many psychiatric patients (the evidence for fish oil in bipolar disorder, for example, is greater than that for the commonly used drug Neurontin), and the main problem people seem to have with it is burping up a fishy taste. That can be avoided by using a relatively high quality supplement, which tends to taste less like fish.
Dr. Mike Merrill is an internist practicing in Buffalo. His column appears once a month on this page. E-mail your comments to him at firstname.lastname@example.org.