Antidepressants value over placebo limited

New research has cast doubt on the efficacy of antidepressant medication over placebo in all but the most severe cases of depression. The US meta-analysis included six trials comprising more than 700 adult patients, who received either the tricyclic antidepressant imipramine, the SSRI paroxetine or a placebo for at least six weeks. Drug therapy was significantly more beneficial than placebo only in patients who had very severe depression, as defined by a Hamilton Depression Rating Scale score of 25 or higher. "True drug effects were non-existent to negligible among depressed patients with mild, moderate and even severe baseline symptoms, whereas they were large for patients with very severe symptoms," the study authors wrote in the Journal of the American Medical Association. The finding was important since most of the cases doctors saw were in the mild-to-moderate range, the authors said. However, Professor Nicholas Keks, professor of psychiatry at Melbourne's Monash University, said categorising depression by severity was simplistic and doctors needed to also consider the nature of the depression. It was often more useful, he said, to think of depression as melancholic or non-melancholic, with the former characterised by changes that "give antidepressants a biology to work on". Professor Ian Hickie, executive director of the University of Sydney's Brain and Mind Research Institute, said it was not that the response to drugs increased in severe illness, but rather that the response to placebo decreased. "The takeout [message] is, psychological treatments up-front for the less severe forms of depression, and the use of antidepressants only in those patients who don't respond within 4-6 weeks," Professor Hickie said. "You could also make the argument for medical treatments first up in severe cases."...