Effect of trajectory of employment status on all-cause mortality in the late middle-aged and older population: results of the Korea Longitudinal Study of Aging (2006-2020)

OBJECTIVES: This study conducted a longitudinal analysis of the effect of trajectory of employment status (TES) on all-cause mortality in late middle-aged and older Koreans based on the Korean Longitudinal Study of Aging (KLoSA). METHODS: After excluding missing values, data on 2,774 participants were analyzed using the chi-square test and the group-based trajectory model (GBTM) for data from the first to fifth KLoSA and the chi-square test, log-rank test, and Cox proportional hazard regression for data from the fifth to eighth KLoSA. RESULTS: The GBTM analysis identified 5 TES groups: sustained white collar (WC; 18.1%), sustained standard blue collar (BC; 10.8%), sustained self-employed BC (41.1%), WC to job loss (9.9%), and BC to job loss (20.1%). Compared to the sustained WC group, the WC to job loss group had higher mortality at 3 years (hazard ratio [HR], 4.04, p=0.044), 5 years (HR, 3.21, p=0.005), and 8 years (HR, 3.18, p<0.001). The BC to job loss group had higher mortality at 5 years (HR, 2.57, p=0.016) and 8 years (HR, 2.20, p=0.012). Those aged 65 years and older and males in the WC to job loss and BC to job loss groups had an increased risk of death at 5 years and 8 years. CONCLUSIONS: There was a close association between TES and all-cause mortality. This finding highlights the need for policies and institutional measures to reduce mortality within vulnerable groups with an increased risk of death due to a change in employment status.