Social Isolation, Loneliness, and All-Cause Mortality in Patients With Cardiovascular Disease: A 10-Year Follow-up Study

Objective Social isolation and loneliness have been associated with increased incidence of cardiovascular disease (CVD), but few studies have evaluated the impact of social isolation and loneliness on mortality in people with existing CVD, and these are limited to Western populations. We examined whether social isolation and loneliness are associated with increased risk of mortality in individuals with established CVD in Taiwan. Methods The cohort was composed of 1267 patients with confirmed CVD 65 years or older followed up for up to 10 years. Cox proportional hazard regression models were used to examine the association between social isolation and loneliness at baseline and mortality at follow-up by adjusting for demographic variables, health-related behaviors, and health status. Results There were 593 deaths during the follow-up period. Social isolation was associated with increased risk of mortality after accounting for established risk factors (hazard ratio [HR] = 1.16; 95% confidence interval [CI] = 1.06-1.26), whereas loneliness was not associated with increased risk of mortality (HR = 0.95; 95% CI = 0.82-1.09). When both social isolation and loneliness were included in the model, social isolation maintained an association with mortality (HR = 1.16; 95% CI =1.07-1.27). Conclusions Social isolation is associated with an increased risk of mortality in patients with CVD, and the effects are independent of loneliness. These findings expand our knowledge about the impact of social isolation on the outcomes of CVD in non-Western countries. Efforts to reduce isolation may have substantial benefits in terms of mortality in patients with CVD.