Prediction of relapse with the TRH test and prophylactic amitriptyline in 39 patients with endogenous depression

The authors conducted a double-blind prospective study of 39 patients with unipolar endogenous depression who recovered after ECT. Thyrotropin (TSH)-releasing hormone (TRH) tests were performed before and after ECT. Patients were divided into three groups on the basis of their altered TSH response: Persistent remission was predicted for patients in group 1 (N = 15) and relapse was predicted for groups 2A (N = 13) and 2B (N = 11). Patients in groups 1 and 2A received placebo and those in group 2B received amitriptyline for 6 months. Fewer relapses occurred in groups 1 and 2B than in group 2A (p less than .05), showing that relapse can be predicted by the TRH test and prevented by amitriptyline.