The study found that the 4.7 percent of the women in the study with 17 to 20 health index points were at much lower risk of stroke overall and of ischemic stroke, compared women with zero-to-four health index points.
"Our findings show the importance of healthy behaviors in the prevention of total and ischemic stroke," the study authors concluded.
The U.S. National Women's Health Information Center has more about heart disease and stroke.
"Because we've had some experience where it may not as clear to authors as it should be, we have tightened our conflict-of-interest statement," said Dr. Catherine D. DeAngelis, editor-in-chief of the Journal of the American Medical Association. "We want utmost transparency."
The move came as welcome news to outside observers.
"The earlier policies left some discretion for individuals to determine what was a 'relevant' conflict of interest," said Dr. Mark Fendrick, a professor of internal medicine at the University of Michigan School of Medicine in Ann Arbor. "Given the multitude of examples where investigators and authors could not police themselves, I believe the new JAMA conflict-of-interest policy is unfortunately required."
The announcement comes in response to the revelation that authors of a recent article on antidepressants had failed to disclose ties to several different drug companies.
Three letters-to-the-editor in the July 12 issue of JAMA responded to the original study, which found that pregnant women who discontinued their antidepressant medication were at a five times higher risk of relapse than women who didn't.
Two of the letters discussed the science of the study but the third, from Dr. Adam Urato of Tufts University-New England Medical Center, noted the "apparent failure [of seven of the authors] to provide appropriate financial disclosure."
According to Urato's letter, readers weren't privy to the fact that "the majority of the authors have been paid by companies that manufacture antidepressants, and that the lead author [Dr. Lee Cohen of Massachusetts General Hospital] appears to have received support from at least eight such companies."
In reply, the authors stated that they had omitted the disclosures because the article did not deal with any specific medications. In retrospect, however, they conceded that "given the implications of these findings relating to potential antidepressant use during pregnancy, we regret that we failed to include disclosures of the financial associations of all of the authors. Such disclosures would have provided utmost transparency with respect to potential conflict of interest, and we wholeheartedly support such a practice."
But this wasn't the first time such an episode had unfolded in the pages of the journal and the editors of JAMA have now decided to formalize their quest for "utmost transparency."
"Just in case authors are not quite understanding our policy, we published this editorial, mostly to eliminate -- at least as far as we know now -- any way for people to misinterpret what we mean," DeAngelis said. "We now make it very specific."
Authors now must disclose any financial or other relationship with any company, even if a specific medication is not mentioned in the article. Also, mention of any relationship must be made not just at the end of the article, but also in the body of the piece.
The editors give an example: Authors of a manuscript about hypertension need to report all financial relationships with manufacturers of hypertension products, not just relationships with companies whose specific products are mentioned in the article.
This latest installment is really a minor episode in an ongoing saga which casts doubt on the independence of medical research.
Recent studies focused on conflict of interest (some of them published in JAMA) have found that doctors who participated in a drug-company-sponsored trial of asthma medications were more likely to prescribe that company's drugs; that clinical trials funded by drug companies and other for-profit entities were more likely to report positive findings for the drug in question than similar trials funded by nonprofit groups; and that industry is paying for more and more medical research.
Perhaps the most egregious example of drug company influence on clinical trials involved Vioxx, the cox-2 inhibitor painkiller removed from the market in September 2004 after a study tied its use to increased cardiovascular events.
Last December, editors of the prestigious New England Journal of Medicine editors published a rare "Expression of Concern" letter charging that a major study on the drug was submitted to the journal only after data on cardiovascular events among Vioxx trial participants was deleted by Merck, which makes Vioxx and funded the trial.
Just last month, the NEJM issued a rare correction on another influential 2005 study on the painkiller. The correction retracted the author's initial claim of an 18-month delay before patients experience increased cardiovascular risks. The correction now states that there is no such delay in the risk. That study was also funded by Merck.
More information
Learn more about psychiatric disorders during pregnancy at the American Pregnancy Association.
