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Unipolar depression in adults: Epidemiology, pathogenesis, and neurobiology

Ranga Krishnan, MD
Section Editor
Peter P Roy-Byrne, MD
Deputy Editor
David Solomon, MD


Depression is a major public health problem associated with increased functional disability and mortality. In the United States in 2010, the estimated annual economic consequences of unipolar major depression, including direct medical costs and workplace costs, exceeded 200 billion dollars [1].

The epidemiology, pathogenesis, and neurobiology of depression in adults are reviewed here. The clinical features, course of illness, assessment, diagnosis, and treatment of depression are discussed separately.

(See "Unipolar depression in adults: Clinical features".)

(See "Unipolar depression in adults: Course of illness".)

(See "Unipolar depression in adults: Assessment and diagnosis".)


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