Prevalence of seasonal depression in a prospective cohort study.
The prevalence of autumn/winter seasonality in depression has been documented in the longitudinal Zurich cohort study by five comprehensive diagnostic interviews at intervals over more than 20 years (N = 499). Repeated winter major depressive episodes (MDE-unipolar + bipolar) showed a prevalence of 3.44% (5× more women than men), whereas MDE with a single winter episode was much higher (9.96%). A total of 7.52% suffered from autumn/winter seasonality in major and minor depressive mood states. The clinical interviews revealed novel findings: high comorbidity of Social Anxiety Disorder and Agoraphobia within the repeated seasonal MDE group, high incidence of classic diurnal variation of mood (with evening improvement), as well as a high rate of oversensitivity to light, noise, or smell. Nearly twice as many of these individuals as in the other MDE groups manifested the syndrome of atypical depression (DSM-V), which supports the prior description of seasonal affective disorder (SAD) as presenting primarily atypical symptoms (which include hypersomnia and increase in appetite and weight). This long-term database of regular structured interviews provides important confirmation of SAD as a valid diagnosis, predominantly found in women, and with atypical vegetative symptoms.
['Wirz-Justice|Anna|A|', 'Ajdacic|Vladeta|V|', 'Rössler|Wulf|W|', 'Steinhausen|Hans-Christoph|HC|', 'Angst|Jules|J|http://orcid.org/0000-0002-5186-1690']
D000328:Adult D000379:Agoraphobia D015897:Comorbidity D016208:Databases, Factual D003865:Depressive Disorder, Major D005260:Female D006801:Humans D007406:Interview, Psychological D008137:Longitudinal Studies D008297:Male D008875:Middle Aged D000072861:Phobia, Social D016574:Seasonal Affective Disorder D013557:Switzerland D055815:Young Adult
Seasonality Affective disorders Comorbid disorders Zürich longitudinal cohort study