Total and Premature Mortality in Single-Person Households: Comparative Study of Korean and UK Data

To investigate the relationship between living in a single-person household and risk of mortality, particularly premature mortality.

Using data from the Korean National Health Information Database (NHID) (n=2,443,202) and the UK Biobank (n=496,925), this study analyzed the mortality risks associated with living alone in the middle-aged population. We performed Cox proportional hazard regression analyses for the association of single-person household status with total and premature mortality and further examined associated factors. Causal mediation analyses were conducted on the mediating factors leading to death in these households.

Middle-aged individuals living alone had higher risks of total mortality (hazard ratio, 1.25 [95% CI, 1.22 to 1.27] in NHID, 1.22 [95% CI, 1.18 to 1.25] in UK Biobank) and premature mortality (hazard ratio, 1.27 [95% CI, 1.20 to 1.33] in NHID, 1.43 [95% CI, 1.33 to 1.52] in UK Biobank) after adjusting for social and lifestyle factors, metabolic diseases, and cancer. Duration of living alone elevated mortality risk, while living in a multiperson household reduced it. Healthy lifestyle habits decreased mortality risks, especially for those living alone. Income, mental health, and smoking were key mediators.

Living alone is associated with higher mortality risks, which emphasizes the need for tailored medical interventions and robust social support, particularly for those with unhealthy lifestyle habits or low income. Promoting healthy behaviors is crucial to mitigating these risks.