background Major depressive disorder (mdd) tends to be chronic. However, few studies have examined the long-term course of mdd in primary care.
aim To examine the 39-month natural history of mdd in adult primary care patients, and whether the outcome is related to severity of depression.
methods Prospective cohort study of 1338 consecutive attendees with follow-up after six, 12 and 39 months with dsm-iv mdd and severity of depression (phq-9) at each assessment.
results At baseline, mdd was present in 13%. Of these, 38% remained depressed or were again depressed after 39 months, and 20% were in remission but had multiple episodes. Patients with a chronic or recurrent course had severer depressive symptoms at baseline than those who remitted.
conclusion The majority of patients with mdd attending primary care have a chronic or recurrent course. Furthermore, chronic and intermittent course patterns are associated with higher levels of severity of depression.