The prophylactic efficacy of tricyclic antidepressants--a five year followup

1. In order to evaluate the efficacy of antidepressants in the prevention of recurrent depression, a longitudinal life-table analysis was carried out involving 217 unipolar patients whose depressive symptoms had remitted following treatment with one of five standard tricyclics (imipramine, amitriptyline, desipramine, nortriptyline, and doxepin). 2. Following six months continued euthymic mood these patients were maintained on the medication to which they initially responded to in a clinical setting over a 5 year period. These patients were compared against a group of 28 individuals who were treated acutely for their depression and responded to one of the above the 5 standard antidepressants, but following 5-6 months continuation treatment were taken off the antidepressant at their own request. 3. Though there was a lower rate of relapse in patients receiving active medication vs the no treatment group, the frequency of relapse was high for the group on active drug. 4. Using the longitudinal life-table method of Fleiss there was a pessimistic-optimistic average relapse rate of 30%, 50%, and 60%, at 1, 2, and 3 years respectively while on active drug vs a 51%, 74%, and 83% relapse rate on no treatment. Overall 87 of 217 patients on active drug (40.1%) were observed to have suffered a depressive relapse over the 5 year course.