Long-term follow-up of chronic depression treated with imipramine.

A long-term follow-up assessment was conducted in 25 chronically depressed patients who had participated in a 6-week trial of imipramine to determine if imipramine responders would sustain a more favorable long-term outcome than nonresponders or noncompleters. Imipramine responders tended to remain on imipramine treatment throughout the follow-up interval and had a significantly better outcome. Eighty-nine percent of the imipramine responders met the criteria for recovery at follow-up compared with 31% in the comparison groups. Imipramine responders also fared significantly better at follow-up on measures of depression, global severity of illness, and social/vocational functioning. The results supported a more favorable long-term outcome in chronic depression patients who had responded to imipramine and suggest that maintenance therapy may be indicated and effective for this disorder.