Does incomplete recovery from first lifetime major depressive episode herald a chronic course of illness?

Objective: This study investigated the influence of incomplete recovery fro m first lifetime major depressive episodes on longterm outcome. Method: After their first lifetime major depressive episode, patients were divided into asymptomatic (N=70) and residual subthreshold depressive sympt om (N=26) recovery groups and compared on longitudinal course during up to 12 years of prospective naturalistic follow-up. Results: Patients with residual subthreshold depressive symptoms during rec overy had significantly more severe and chronic future courses. Those with residual symptoms relapsed to major and minor depressive episodes faster an d had more recurrences, shorter well intervals, and fewer symptom-free week s during follow-up than asymptomatic patients. Conclusions: Resolution of major depressive episodes with residual subthres hold depressive symptoms, even the first lifetime episode, appears to be th e first step of a more severe, relapsing, and chronic future course. When o ngoing subthreshold symptoms continue after major depressive episodes, the illness is still active, and continued treatment is strongly recommended.