Researchers published their findings online in the Journal of Affective Disorders.
“This very large, population-based study provides evidence of seasonal variations in depressive symptoms, which appear to be more pronounced in women than in men,” said researcher Daniel Smith, MD, a professor of psychiatry at the University of Glasgow, Scotland.
“We don’t yet fully understand why this should be the case, but it was interesting that the changes were independent of social and lifestyle factors, perhaps suggesting a sex-specific biological mechanism.”
“Clearly, this is a complex but important area which requires further study,” Dr. Smith said.
The study involved participants from the UK Biobank cohort. Researchers looked at depressive symptoms overall as well as symptoms of low mood, anhedonia or inability of experience pleasure, tenseness, and tiredness by season, day length, and outdoor temperature.
“Clinicians should be aware of these population-level sex differences in seasonal mood variation,” Dr. Smith said, “to aid the recognition and treatment of depressive symptoms across the calendar year.”