A total of 219 inpatients with a DSM-III diagnosis of major depression, (150 women and 69 men), were followed prospectively for three to ten years and mortality was recorded. The patients were previous participants in psychopharmacological multicentre trials, which were carried out for the purpose of comparing the antidepressant effect of newer selective serotonin reuptake inhibitors (SSRI), citalopram and paroxetine, with that of the tricyclic antidepressant drug, clomipramine. Diagnostic classification according to the Newcastle-I Scale into endogenous and nonendogenous depression was performed. The observed mortality was significantly greater than that expected. The increased mortality was essentially due to suicides and mainly found among women. Patients scored as being nonendogenously depressed had a significantly higher suicide rate than endogenously depressed patients. The excess number of suicides in the nonendogenous group largely occurred within the first year of observation. No association was found between response to the antidepressant treatment in the trial and the suicide risk during the first three years of observation.