The Small Specific Effects of Antidepressants in Clinical Trials: What Do They Mean to Psychiatrists?
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Although antidepressants continue to be a mainstay for clinicians who treat people suffering from depressive disorders, there have recently been articles published in both the scientific literature and the popular press that have raised questions about the utility of this class of medications. This paper briefly examines recent meta-analyses that have reported small drug versus placebo differences in randomized controlled trials and, from the perspective of a prescribing psychiatrist, discusses the clinical significance of these findings. It is concluded that antidepressants do have relatively modest effects (as compared with placebo) in contemporary randomized controlled trials, and that the contribution of placebo-expectancy factors to individual outcomes is often underestimated. Nevertheless, it is also concluded that the modest benefits of antidepressants in grouped datasets obscure large, specific, and very meaningful therapeutic effects for 10% to 20% of those treated with antidepressants.
KeywordsAntidepressants Placebo Meta-analysis Randomized controlled trials RCT Clinical trials Psychiatrists
Dr. Thase has served as a consultant for Alkermes, AstraZeneca, Bristol-Myers Squibb, Eli Lilly and Company, Dey Pharma, Forest Laboratories, Gerson Lehrman Group, GlaxoSmithKline, Guidepoint Global, H. Lundbeck A/S, MedAvante, Merck & Co. (formerly Schering-Plough and Organon Pharmaceuticals USA), Neuronetics, Novartis, Otsuka Pharmaceutical Co., Ortho-McNeil Pharmaceuticals (Johnson & Johnson), Pamlab, Pfizer (formerly Wyeth-Ayerst International), PGxHealth, Shire US, Supernus Pharmaceuticals, Takeda Pharmaceuticals North America, and Transcept Pharmaceuticals; has received grant support from the Agency for Healthcare Research and Quality, Eli Lilly and Company, Forest Pharmaceuticals, GlaxoSmithKline, the National Institute of Mental Health, Otsuka Pharmaceutical Co., and Sepracor; has received honoraria from AstraZeneca, Bristol-Myers Squibb, Dey Pharma, Eli Lilly and Company, Merck & Co., Pfizer (formerly Wyeth-Ayerst International); has received royalties from the American Psychiatric Foundation, Guilford Publications, Herald House, and W.W. Norton & Company; has received payment for development of educational presentations (including service on speakers’ bureaus) from Pfizer and Bristol-Myers Squibb; and has held stock/stock options in MedAvante. His wife has been employed by Embryon (formerly Advogent).
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