|dc.description.abstract||Background: Seasonal variations in mood and behaviour, termed seasonality, are commonly reported in the general
population. As a part of a large cross-sectional health survey in Hordaland, Norway, we investigated the relationship
between seasonality, objective health measurements and health behaviours.
Methodology/Principal Findings: A total of 11,545 subjects between 40–44 years old participated, completing the Global
Seasonality Score, measuring seasonality. Waist/hip circumference, BMI and blood pressure were measured, and blood
samples were analyzed for total cholesterol, HDL cholesterol, triglycerides and glucose. Subjects also completed a
questionnaire on miscellaneous health behaviours (exercise, smoking, alcohol consumption). Hierarchical linear regression
analyses were used to investigate associations between seasonality and objective health measurements, while binary
logistic regression was used for analysing associations between seasonality and health behaviours. Analyses were adjusted
for sociodemographic factors, month of questionnaire completion and sleep duration. Seasonality was positively associated
with high waist-hip-ratio, BMI, triglyceride levels, and in men high total cholesterol. Seasonality was negatively associated
with HDL cholesterol. In women seasonality was negatively associated with prevalence of exercise and positively associated
with daily cigarette smoking.
Conclusions/Significance: High seasonality was associated with objective health risk factors and in women also with health
behaviours associated with an increased risk for cardiovascular disease.||en