In a study to be published in the Nov. 12 special edition of the Journal of the American Medical Association (JAMA), researchers at McGill University, Johns Hopkins University and six other institutions from around the world question the American Heart Association's recent suggestion that millions of North American cardiac patients be automatically screened for depression. Such screening would involve administering a questionnaire and other tests to try to identify individuals who might have had no history or clinical indications of depression but who may, nonetheless, be depressed.
The AHA maintains that the link between depression and cardiac care is important.
But Dr. Brett Thombs of McGill and the affiliated Jewish General Hospital, and Dr. Roy Ziegelstein, of Johns Hopkins, say there is not nearly enough medical evidence to support such a "massive, expensive and labour-intensive undertaking," and in fact provide evidence that testing for depression would not benefit patients in a cardiac care environment.
"It's a very appealing idea that non-mental health professionals can administer a quick, easy-to-use depression screening test, and that would somehow benefit patients," said Thombs, a psychologist and assistant professor in the Department of Psychiatry at McGill's Faculty of Medicine and at the JGH. "Unfortunately, the reality is that it would be an extremely difficult undertaking that wouldn't produce practical benefits for patients."
The study drew upon a collection of more than 1,500 clinical studies from around the world, of which 17 were selected for detailed review.
"We discovered that screening alone or screening and referral doesn't help most patients. This is true even in primary care where the doctor is usually better trained than a cardiologist to manage depression," said Thombs. "We see positive effects only in 'enhanced care' or 'collaborative care,' environments where they have mental-health specialists on call. And even there we only see tiny effects."
The researchers found that treating depression in people with heart disease only accounted for a 1 per cent to 4 per cent change in symptoms compared with those treated with placebo. This result, Ziegelstein said, is "too low to expect meaningful benefits for most people, particularly since screening methods are not very precise in identifying people who would benefit from the treatment."
"Moreover, we found no connection at all between getting treated for depression and cardiovascular outcomes, like having a subsequent heart attack," Thombs added. "That said, in no sense are we saying that depression doesn't matter. Depression leads to a great deal of suffering, cardiovascular effects aside, and it can definitely affect how well people take care of themselves after they've had a heart attack.
"We're just saying we don't have the tools in cardiovascular care settings to identify and improve the lives of people who aren't already being treated for depression. What we really need is more research on how best to help heart disease patients adopt healthy behaviours that combat depression, such as how to stop smoking, exercise regularly and maintain a healthy weight."
Source: McGill University