Living alone is associated with all-cause and cardiovascular mortality: 32 years of follow-up in the Copenhagen Male Study

As a consequence of modern urban life, an increasing number of individuals are living alone. Living alone may have potential adverse health implications. The long-term relationship between living alone and all-cause and cardiovascular mortality, however, remains unclear.

Participants from The Copenhagen Male Study were included in 1985–86 and information about conventional behavioural, psychosocial, and environmental risk factors were collected. Socioeconomic position (SEP) was categorized into four groups. Multivariable Cox-regression models were performed with follow-up through the Danish National Registries. A total of 3346 men were included, mean (standard deviation) age 62.9 (5.2) years. During 32.2 years of follow-up, 89.4% of the population died and 38.9% of cardiovascular causes. Living alone (9.6%) was a significant predictor of mortality. Multivariable risk estimates were [hazard ratio (95% confidence interval)] 1.23 (1.09–1.39), P = 0.001 for all-cause mortality and 1.36 (1.13–1.63), P = 0.001 for cardiovascular mortality. Mortality risk was modified by SEP. Thus, there was no association in the highest SEP but for all other SEP categories, e.g. highest SEP for all-cause mortality 1.01 (0.7–1.39), P = 0.91 and 0.94 (0.6–1.56), P = 0.80 for cardiovascular mortality; lowest SEP 1.58 (1.16–2.19), P = 0.004 for all-cause mortality and 1.87 (1.20–2.90), P = 0.005 for cardiovascular mortality. Excluding participants dying within 5 years of inclusion (n = 274) did not change estimates, suggesting a minimal influence of reverse causation.

Living alone was an independent risk factor for all-cause and cardiovascular mortality with more than three decades of follow-up. Individuals in middle- and lower SEPs were at particular risk. Health policy initiatives should target these high-risk individuals.