The Impact of Long Working Hours on Cognitive Function: A Follow-Up Study with Gender Stratification

Abstract

Background: Recent studies have shown that long working hours can have adverse consequences on health and possibly trigger biological processes that mediate the relationship between long working hours and cognitive decline. Objective: To investigate whether long working hours and the overall duration such exposure is associated with a decline in cognitive function. Methods: Data obtained during the Korean Longitudinal Study on Aging (n = 2,518) during the period 2006-2018 were used to explore the relationship between long working hours and cognitive decline. Korean version of the Mini-Mental State Examination (K-MMSE) scores were used to evaluate cognitive function. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs), which were used to evaluate declines in K-MMSE scores over the 12-year study period. Results: Overall HR (95% CI) for a decline in cognitive function in long working hours group was 1.13 (0.73-1.17). When categorized by sex, women with long working hours had an HR (95% CI) of 1.50 (1.05-2.22), K-MMSE scores decreased significantly after working long hours for 5 years (p < 0.01). Conclusion: The study furthers understanding of the effects of long working hours on cognitive decline among female workers. Further research is required to determine the effects of long working hours on cognitive functions.