July 21, 2010
By: David Gutierrez
Newsweek has published a feature article exposing what many psychology researchers refer to as “the dirty little secret”: that antidepressant drugs do not work any better than placebo pills.
Author Sharon Begley notes that while antidepressants do in fact cause improvement in 75 percent of patients, so do placebo pills. In a landmark 1998 study, researchers Irving Kirsch and Guy Sapirstein found that a full 75 percent of antidepressants’ effectiveness could be attributed to the placebo effect.
Upon facing criticism for not including every study in their analysis, Kirsch and Sapirstein used the Freedom of Information Act to acquire data from all corporate-funded antidepressant studies submitted to the FDA. Two interesting facts emerged. First, the researchers found that 40 percent of studies conducted had gone unpublished, significantly higher than the 22 percent for other drugs.
“By and large, the unpublished studies were those that failed to show a significant benefit,” Kirsch said.
Second, when all studies were included, the drugs came out less effective, with placebo accounting for 82 percent of their effectiveness. The non-placebo improvement was only 1.8 points on the 54-point depression diagnostic scale. Sleeping better counts for six points.
The Newsweek article further notes that even those extra 1.8 points can be attributed to placebos: people in drug studies who experience side effects realize they are taking a real drug, which makes their placebo reaction stronger. The placebo effect also explains the increased effectiveness of higher drug doses, and why sometimes a second or third drug is effective when the first failed. It all comes down to belief.
These findings have serious implications for the entire premise on which antidepressant drugs rest: the chemical theory of depression. Other than the presumed effectiveness of antidepressants — a presumption called into question yet again by a recent study in the Journal of the American Medical Association — there is literally no evidence to support this theory.
“Direct evidence doesn’t exist,” Begley writes. “Lowering people’s serotonin levels does not change their mood.”
January 06, 2010
Los Angeles Times
By Shari Roan
Antidepressant medications probably provide little or no benefit to people with mild or moderate depression, a new study has found. Rather, the mere act of seeing a doctor, discussing symptoms and learning about depression probably triggers the improvements many patients experience while on medication.
Only people with very severe depression receive additional benefits from drugs, said the senior author of the study, Robert J. DeRubeis, a University of Pennsylvania psychology professor. The research was released online Tuesday and will be published today in the Journal of the American Medical Assn.
Hundreds of studies have attested to the benefits of antidepressants over placebos, DeRubeis said. But many studies involve only participants with severe depression. Confusion arises, he said, “because there is a tendency to generalize the findings to mean that all depressed people benefit from medications.”
The current analysis attempted to quantify how much of antidepressants’ benefit is attributable to chemical effects on the brain and how much can be explained by other factors, such as visiting a doctor, taking action to feel better or merely the passage of time.
Researchers reviewed six randomized, placebo-controlled studies with a total of 718 patients who took either an antidepressant or placebo. The patients were adults with levels of depression ranging from mild to very severe based on the Hamilton Depression Rating Scale, a questionnaire widely used in depression research. The studies did not exclude patients who were likely to have a strong response to a placebo. Researchers then compared the patients’ depression scores at the beginning of treatment with those after at least six weeks of treatment.
The study found that the magnitude of the drugs’ benefit increased with the baseline level of depression. The effect of treatment was similar in people with mild, moderate and severe symptoms, regardless of whether they took an antidepressant or placebo. Only the people who rated very severe on the depression scale at the start of the study showed measurable improvements on antidepressants.