Living alone is a risk factor for mortality in men but not women from the general population:: a prospective cohort study

Background: During the past decades a rising trend of living alone can be observed in the population especially in urban areas. Living alone is considered a psychosocial risk factor. We studied the relationship between living alone, cardiovascular risk factors and mortality. Methods: We analysed data from the population-based MONICA/KORA cohort study including 3596 men and 3420 women of at least one of three surveys carried out between 1984 and 1995 in the region of Augsburg, Germany. They were between 45 and 74 years old and were followed-up until 31 December 2002. During follow-up 811 men and 388 women died. Cox proportional hazards analysis was used to examine the association between living alone and mortality. Results: Altogether 260 men (7%) and 620 women (18%) were living alone at baseline. Men, who lived alone, were less well educated, had fewer children and friends, and they smoked significantly more than other men. Women, living alone, were also significantly more often current smokers and had less children and friends, but they were more often better educated than cohabitating women. The latter group showed a higher proportion of obese and hypertensive women. Men living alone had a twofold risk to die after multivariable adjustment (hazard ratio = 1.96; p < 0.0001; 95% confidence interval 1.56-2.46). This was not the case for women. Conclusion: Living alone is an independent risk factor for mortality in men. It is unclear whether living alone causes an increased mortality or whether predisposition for increased mortality is responsible for men living alone.