Arcady A. Putilov
Since Seasonal Depressive Disorder (SAD) was “discovered” in the field of biological rhythm research, it was mainly studied and theoretically explained in framework of several biological paradigms. Psychosocial and cultural aspects were not successfully included in theories of this condition and remained to be explored. Earlier investigations of SAD prevalence in USA, Canada, and Europe suggested that women outnumber men in the symptomatic groups. However, those of later reports that were based on data from South and East Asia (e.g., such countries as Japan, China, and India) revealed that sex ratio might be close to 1:1. Prevalence of SAD was assessed in one south region (Turkmenia in Central Asia, 38º N) and in 4 Northern regions (West Siberia, 55º N, South Yakutia, 63-64º N, Chukotka, 64-66º N, and North Yakutia of Asian part of Russia, 66-67º N). Seasonal Pattern Assessment Questionnaire (SPAQ) was administered to groups of residents with mean age 37.5 – 44.4 years (N from 177 to 511). It was found that, in Turkmenia, the most often type was summer SAD (the worst well-being in summer, 13.9 %), whereas in the northern regions this was winter SAD (the worst well-being in winter, 12.5-16.8 %, independently on latitude). Unlike males in the nothern regions and similar to males from South and East Asia, native males from Turkmenia (but not non-native males) outnumbered females in the symptomatic groups. Such result points at influence of cultural factors on SAD prevalence.
