Determinants of Subjective Economic Status and Quality of Life Among Middle- and Older-Aged Koreans: The Roles of Living Costs, Employment, and Smoking Using Korean Longitudinal Study of Data on Older Adults

This study examined how living costs, employment, and smoking are associated with subjective economic status and quality of life among middle-aged Koreans aged 45 to 57, the cohort that will constitute the older population of the coming decades. Drawing on social determinants of health theory, the study specified expenditure on food, vehicles, and housing as curvilinear rather than monotonic correlates of the two outcomes. Data were drawn from the 2022 wave of the Korean Longitudinal Study of Older Adults’ Employment (n = 4392), and quadratic multiple regression models were estimated for each outcome. Food cost and vehicle cost displayed inverted U-shaped associations with subjective economic status, and vehicle cost displayed the same pattern with quality of life, whereas housing cost was negatively and linearly associated with subjective economic status. Employment was positively associated with subjective economic status but negatively associated with quality of life, and smoking was negatively associated with both outcomes. Subjective economic status was, in turn, positively associated with quality of life. These results indicate that the level at which expenditure occurs, rather than expenditure as such, is relevant to how middle-aged Koreans evaluate their economic circumstances and their lives, and they carry implications for welfare policy addressed to the pre-old cohort.