Association between weekly working hours and risky alcohol use: A 12-year longitudinal, nationwide study from South Korea

We aimed to investigate the association between long working hours and onset of risky alcohol use. We included a nationally representative sample comprising 11,226 workers in South Korea (57,887 observations). The Alcohol Use Disorders Identification Test was used to assess risky alcohol use. Fixed effect regressions were employed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Adjusted ORs (95% CIs) of risky alcohol use were 1.08 (0.95–1.22) for 41–48 h/week, 1.12 (0.96–1.31) for 49–54 h/week, and 1.40 (1.21–1.63) for ≥55 h/week, compared with standard working hours (35–40 h/week). ORs (95% CIs) of the association between working ≥55 h/week and risky alcohol use was 1.39 (1.17–1.65) for men and 1.34 (0.98–1.82) for women. Yearly cumulative exposure to long working hours (>40 h/week) is positively associated with risky alcohol use in a dose-dependent manner. For instance, exposure to long working hours for ≥3 years was associated with an increased likelihood of risky alcohol use (OR [95% CI]: 2.20 [1.78–2.72]). Sex-stratified analyses showed that long work hours are associated with risky alcohol use in both male and female workers. Appropriate work-hour policy is needed to prevent workers from risky alcohol use.