Association Between Precarious Employment and Cognitive Decline: A Longitudinal Study of Middle-Aged and Older Workers in Korea

Abstract

BackgroundGlobally, many countries are experiencing rapid aging of their working populations. Moreover, older workers are particularly susceptible to poor employment conditions, which can contribute to health inequalities. ObjectiveWe explored the association between precarious employment (PE) and cognitive decline. DesignA longitudinal analysis of a cohort of Korean workers. ParticipantsWe included a nationwide sample of Korean adults aged >= 45 years (n = 2137), with repeated measurements conducted biennially from 2006 to 2020 (6290 observations). Main MeasuresPE was assessed based on three dimensions: employment insecurity, income inadequacy, and a lack of rights and protection. A summative score was used to categorize an individual's PE into quartiles (lowest, low, high, and highest). Cognitive decline was defined as a decrease in the Mini-Mental State Examination score by >= 3 after a 2-year follow-up. Generalized estimating equations were used to determine the association between PE and cognitive decline. We estimated odds ratios (ORs) and 95% confidence intervals (CIs). Key ResultsThe mean age was 51.6 years, and the mean baseline MMSE score was 28.7. During the study period, cognitive decline was observed in 15.1% of the observations over a 2-year follow-up. Regarding each PE element, workers with the lowest wage (<60% of the median) was associated with increased odds of experiencing cognitive decline (OR, 1.45; 95% CI, 1.02-2.06). Based on a summative score, workers with high or the highest PE levels had increased odds of experiencing cognitive decline (OR, 1.38; 95% CI, 1.07-1.77 for high PE and OR, 1.51; 95% CI, 1.14-1.99 for the highest PE) compared with workers with the lowest PE level. ConclusionsThis study suggests that PE is a risk factor for cognitive decline in workers. Enhancing employment conditions for older adults is crucial for promoting healthy aging.