Suicide Risk in Placebo-Controlled Trials of Treatment for Acute Manic Episode and Prevention of Manic-Depressive Episode

Abstract
The authors' goal was to investigate whether there is a greater suicide risk in the placebo arms of placebo-controlled studies of active medication for the treatment of acute manic episode and the prevention of manic/depressive episode. If so, this would be a strong ethical argument against the conduct of such studies. All placebo-controlled, double-blind, randomized trials of medication for the treatment of acute manic episode and the prevention of manic/depressive episode that were part of a registration dossier submitted to the regulatory authority of the Netherlands, the Medicines Evaluation Board, between 1997 and 2003, were reviewed for occurrence of suicide and attempted suicide. In 11 placebo-controlled studies of the treatment of acute manic episode, including 1,506 patients (117 person-years) in the combined active compound group and 1,005 patients (71 person-years) in the combined placebo group, no suicides and no suicide attempts occurred. In four placebo-controlled studies of the prevention of manic/depressive episode, including 943 patients (406 person-years) in the combined active compound group and 418 patients (136 person-years) in the combined placebo group, two suicides (493/100,000 person-years of exposure) and eight suicide attempts (1,969/100,000 person-years of exposure) occurred in the combined active compound group, but no suicides and two suicide attempts (1,467/100,000 person-years of exposure) occurred in the combined placebo group. Concern about greater risk of suicide or attempted suicide in the placebo group should not be an argument against the conduct of placebo-controlled trials for these indications, provided that appropriate precautions are taken.