Association between social jetlag and anxiety symptoms: Findings from a nationally representative sample of the Korean working population.

Objectives: Social jetlag (SJL), which arises from the misalignment of biological and social rhythms, is associated with adverse health outcomes. We explored the association between SJL and anxiety symptoms in Korean workers.

Methods: This cross-sectional study included a nationally representative sample, consisting of 2731 adult workers. SJL was calculated as the absolute difference in the midpoint between sleep onset and offset times on workdays and free days. The Generalized Anxiety Disorder-7 scale was used to assess anxiety symptoms. Logistic regressions were used to estimate the odds ratios (ORs) and 95 % confidence intervals (CIs).

Results: Among the sample, 66.5 % individuals had 0-59 min of SJL, 22.6 % had 60-119 min of SJL, and 10.9 % had ≥120 min of SJL. The prevalence of anxiety symptoms was 3.4 % for those with 0-59 min of SJL, 3.2 % for those with 60-119 min of SJL, and 7.7 % for those with ≥120 min of SJL. Workers with ≥120 min of SJL, compared with those with 0-59 min of SJL, were associated with an increase in the odds of having anxiety symptoms (OR:2.04, 95 % CI:1.10-3.78). A 1-h increase in SJL is associated with a 1.35-fold increase in the odds of anxiety symptoms (95 % CI:1.04-1.75). This positive association remained robust after adjusting for the effect of sleep deprivation using a sleep-corrected formula.

Conclusion: ≥2 h of SJL is associated with anxiety symptoms in Korean workers. Policy measures are required to mitigate excess SJL and monitor the mental health of workers with high SJL levels.