Association of weekly working hours with poor psychological well-being and moderation by employment status in Korean workers

Effect of long working hours on psychological distress among young workers in different types of occupation

BACKGROUND

We investigated how the association between long working hours and psychological distress varies across different employment and occupation types in young workers.

METHODS

Examining a nationally representative sample of 7246 Korean workers (3621 women) aged 15 to 40, we analyzed 23,492 observations spanning from 2016 to 2020. Psychological distress was measured using the Brief Encounter Psychosocial Instrument. We employed a generalized estimating equation to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Of the total observations, 5.2% worked <35 h/week, 52.9% worked 35-40 h/week, 23.5% worked 41-48 h/week, 10.3% worked 49-54 h/week, and 8.2% worked ≥55 h/week. The OR (95% CI) of the association between long working hours and psychological distress was 1.38 (1.11-1.72) for <35 h/week, 1.47 (1.32-1.65) for 41-48 h/week, 1.74 (1.49-2.04) for 49-54 h/week, and 2.11 (1.75-2.55) for ≥55 h/week compared to 35-40 h/week. The OR (95% CI) of the association between working ≥55 h/week and psychological distress was significantly higher among wage workers (OR [95% CI]: 2.37 [1.94-2.89]) compared to self-employed workers (OR [95% CI]: 0.84 [0.52-1.36]). Additionally, the OR (95% CI) of the association between working ≥55 h/week and psychological distress was significantly higher among white-collar workers (OR [95% CI]: 3.24 [2.54-4.13]) compared to service/sales workers (OR [95% CI]: 1.22 [0.86-1.72]) or blue-collar workers (OR [95% CI]: 1.71 [1.10-2.67]). No clear gender differences were observed.

CONCLUSION

Psychological distress caused by long working hours can be pronounced among white-collar and wage workers.

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.