Social isolation, loneliness, and all-cause mortality: A cohort study of 35,254 Chinese older adults

Abstract

Background: Few studies of social isolation, loneliness and associations with all-cause mortality in older adults have been conducted in non-Western countries. The aim of this study was to conduct such an analysis in a nationally representative sample of Chinese older adults.

Methods: This study used eight waves of data from the Chinese Longitudinal Healthy Longevity Survey from 1998 to 2018 and focused on participants aged ≥60 years. A total of 21,570 people died (61.2%) over a median follow-up of 4.8 years. Social isolation, loneliness, demographic, health and lifestyle factors were measured at baseline. The primary outcome was all-cause mortality. Cox proportional hazard regression models were used to examine the associations of isolation and loneliness with all-cause mortality.

Results: This study included 35,254 participants with mean age of 86.63 ± 11.39 years. Social isolation was significantly associated with an increased mortality (adjusted HR 1.22; 95% CI 1.18-1.25; p < 0.01). The association of loneliness with mortality was nonsignificant after adjustment for health indicators and low psychological well-being (HR 1.01; 95% CI 0.98-1.04; p = 0.69). However, when stratified by age, there was a significant association of loneliness with mortality among participants aged <80 years (HR 1.15; 95% CI 1.05-1.26; p < 0.01).

Conclusions: Social isolation was associated with an increased all-cause mortality among the older Chinese adults. However, loneliness was associated with an increased mortality only among younger participants. Public health interventions aimed at increasing social connectedness may potentially reduce excess mortality among older adults.

Keywords: all-cause mortality; loneliness; older adults; social isolation.