Background: Primary health care provides treatment for most patients with depression. Despite their importance for organizing services, long-term course of depression and risk factors for poor outcome in primary care are not well known.
Method: In the Vantaa Primary Care Depression Study, a stratified random sample of 1119 patients representing primary care patients in a Finnish city was screened for depression with the Primary Care Evaluation of Mental Disorders. SCID-I/P and SCID-II interviews were used to diagnose Axis I and II disorders. The 137 patients with DSM-IV depressive disorder were prospectively followed up at 3, 6, 18 and 60 months. Altogether, 82% of patients completed the 5-year follow-up, including 102 patients with a research diagnosis of major depressive disorder (MDD) at baseline. Duration of the index episode, recurrences, time spent in major depressive episodes (MDEs) and partial or full remission were examined with a life-chart.
Results: Of the MDD patients, 70% reached full remission, in a median time of 20 months. One-third had at least one recurrence. The patients spent 34% of the follow-up time in MDEs, 24% in partial remission and 42% in full remission. Baseline severity of depression and substance use co-morbidity predicted time spent in MDEs.
Conclusions: This prospective, naturalistic, long-term study of a representative cohort of primary care patients with depression indicated slow or incomplete recovery and a commonly recurrent course, which need to be taken into account when developing primary care services. Severity of depressive symptoms and substance use co-morbidity should be systematically evaluated in planning treatment.