Winter depression and functional impairment among ambulatory primary care patients.

This study of primary care patients sought to estimate the prevalence of and functional impairment associated with winter-seasonal depression. Three hundred three patients visiting a primary care clinic in January or February were assessed for seasonal patterns of health change, current DSM-III-R major depressive disorder (MDD), and current functional status. Approximately 9% of patients met criteria for MDD with winter-seasonal pattern, and an additional 29% reported seasonal mood changes without meeting criteria for current MDD. Multivariate analysis revealed that the functional impairment associated with such winter seasonality exceeded that associated with any of the common chronic medical conditions measured, and that such dysfunction was evident even in the absence of a diagnosable depressive disorder (MDD). Winter-seasonal pain was reported by one quarter of the overall sample and by half of those with current MDD, supporting preliminary reports that pain may be a common presenting symptom in seasonal affective disorder. The findings suggest that efforts at detection and treatment of such syndromes in primary care settings would be justified.