Association between living alone and incident type 2 diabetes among middle-aged individuals in Korea: a nationwide cohort study

We studied the association between living alone and the risk of incident type 2 diabetes in middle-aged individuals using nationwide cohort data from the Korean population. 11,686, 677 middle-aged individuals aged 40–64 years who underwent health examinations by the Korean National Health Insurance System between 2009 and 2012 were followed up until December 31, 2015. The hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards regression analysis. During the median follow-up duration of 5.6 years, 393,438 individuals developed type 2 diabetes. Living alone was significantly associated with incident type 2 diabetes in all adjusted models (HR 1.08; 95% CI 1.07–1.09 in model 4). Individuals who lived alone for < 1 year and 1–7 years were associated with increased HRs of 1.07 (1.04–1.09) and 1.08 (1.07–1.09). Living alone was associated with incident type 2 diabetes in all subgroups. The association was stronger in men than in women and younger individuals than in older individuals. Living alone, even for a short duration, may be an important factor in type 2 diabetes development. Better household conditions and appropriate support to one-person households may be needed to prevent type 2 diabetes.