Socioeconomic Vulnerability, Mental Health, and Their Combined Effects on All-Cause Mortality in Koreans, over 45 Years: Analysis of Korean Longitudinal Study of Aging from 2006 to 2014.

Background: We evaluated the effects of socioeconomic factors and psychosocial factors, both individually and combined, on all-cause mortality risk (mortality risk).

Methods: We conducted an 8-year (2006-2014) longitudinal analysis of 10,247 individuals who took part in the Korean Longitudinal Study of Aging, a nationwide survey of people aged 45-79 years. Socioeconomic vulnerability (SEV) was assessed with factors such as education, household income, commercial health insurance, and residential area. Mental health (MH) was assessed with factors such as depression, social engagement, and life satisfaction. The covariates were age, gender, marital status, cohabiting, number of chronic diseases, and health behaviors such as regular exercise, smoking, and alcohol intake. We used a Cox proportional hazard analysis to investigate the effects of SEV and MH on mortality risk and also to analyze the superimposed effects of SEV-MH on mortality risk.

Results: After the controlling for the covariates, high SEV and negative MH were found to be strong predictors of all-cause mortality. The highest quartile of SEV (vs. lowest) had a 1.70 times greater mortality risk (hazard ratio [HR], 1.70; 95% confidence interval [CI], 1.24-2.33) and the highest quartile of MH (vs. lowest) had a 2.13 times greater mortality risk (HR, 2.13; 95% CI, 1.72-2.64). Being in the highest quartile for both SEV and MH (vs. lowest) increased mortality risk more than 3 times (HR, 3.11; 95% CI, 2.20-4.40).

Conclusion: High SEV and negative MH were independently associated with increased mortality risk, and their superimposed effects were associated with an increased risk of mortality.