This is a guest column by Ivan Oransky, M.D., who is executive editor of Reuters Health and blogs at Embargo Watch and Retraction Watch.
One of the things that makes evaluating medical evidence difficult is knowing whether what’s being published actually reflects reality. Are the studies we read a good representation of scientific truth, or are they full of cherry-picked data that help sell drugs or skew policy decisions?
That question may sound like that of a paranoiac, but rest assured, it’s not. Researchers have worried about a “positive publication bias” for decades. The idea is that studies showing an effect of a particular drug or procedure are more likely to be published. In 2008, for example, a group of researchers published a New England Journal of Medicine study showing that nearly all — or 94 percent — of published studies of antidepressants used by the FDA to make approval decisions had positive results. But the researchers found that when the FDA included unpublished studies, only about half — or 51 percent — were positive.
A PLoS Medicine study published that same year found similar results for studies long after drugs were approved: Less than half — 43 percent — of studies used by the FDA to approve 90 drugs were published within five years of approval. It was those with positive results that were more likely in journals.
All of that can leave the impression that something may work better than it really does. And there is at least one powerful incentive for journals to publish positive studies: Drug and device makers are much more likely to buy reprints of such reports. Such reprints are highly lucrative for journals. Read more »
*This blog post was originally published at Gary Schwitzer's HealthNewsReview Blog*
Three recent stories lead me to my opening topic for the year: The value of open-mindedness. This characteristic — a state of receptiveness to new ideas — affects how we perceive and process information. It’s a quality I look for in my doctors, and which I admire especially in older people.
Piece #1 — On the brain’s maturity, flexibility and “cognitive fitness”
For the first piece, I’ll note a Dec 31 op-ed piece that appeared in the New York Times: This Year, Change Your Mind, by Dr. Oliver Sacks, the neurologist and author. In this thoughtful essay, he considers the adult brain’s “mysterious and extraordinary” power to adapt and grow: “I have seen hundreds of patients with various deficits — strokes, Parkinson’s and even dementia — learn to do things in new ways, whether consciously or unconsciously, to work around those deficits.”
With appropriate and very-real respect, I question Sacks’ objectivity on this subject — he’s referred some of the most outstanding (i.e. exceptional) neurological cases in the world. And so it may be that his careful reports are perfectly valid but not representative; for most of us, the adult brain’s capacity to establish new circuitry for language learning or music appreciation may be limited. What his stories do show is that unimaginably strange things happen in our brains, at least occasionally. And maybe we should just accept that and take notes (as he does so carefully), and keep an open mind. Read more »
*This blog post was originally published at Medical Lessons*
Scientists know that our perceptions about taste and texture drive our food preferences. They know quite a lot about the role of taste in this regard, and the results of some recent experiments have shed new light on the role of texture as well, particularly as it relates to foods containing starch.
Starch is a major component of potatoes, rice, corn, wheat and the enormous variety of foods derived from them. It is also added to many other products from maple syrup to pudding. In fact, starch accounts for 40 to 60 percent of the calorie content in the average Western diet, and more than that in many Asian and third-world diets.
Humans begin digesting starch in the mouth, where the salivary glands secrete an enzyme known as amylase. This enzyme breaks down starch and other complex carbohydrates into simpler sugar molecules which end up being absorbed from the small intestine into the bloodstream. Read more »
*This blog post was originally published at Pizaazz*
A study published in the July PLoS Medicine is getting a lot of press for its conclusion that strong social networks are related to increased lifespan.
The meta-analysis of 148 studies involving 308,849 people found that those with stronger relationships were 50 percent more likely to survive over 7.5 years of follow-up. What’s more, the researchers reported that a lack of strong social ties is as bad healthwise as drinking or smoking, and worse than not exercising or being obese.
But although the association between strong social ties and improved longevity seems robust, other factors could be at play, and applying the findings in clinical practice could be difficult. And sorry, Facebook fanatics: Online “friendships” aren’t thought to count as much as in-person ones do. (PLoS Medicine, New York Times, TIME, The Atlantic)
*This blog post was originally published at ACP Internist*