A systematic review and meta-analysis of 90 cohort studies on social isolation, loneliness, and mortality.
Associations between social isolation, loneliness, and the risk of all-cause mortality, cardiovascular disease (CVD), and cancer are controversial. We systematically reviewed prospective studies on the association between social isolation, loneliness, and mortality outcomes in adults over 18 years of age, as well as studies on these relationships in people with CVD or cancer, and performed a meta-analysis.
The study protocol was registered with PROSPERO (reg. no. CRD42022299959). A total of 90 prospective cohort studies involving 2,205,199 people were included.
Here we show that, in the general population, both social isolation and loneliness were significantly associated with an increased risk of all-cause mortality (pooled effect size for social isolation, 1.32; confidence interval (CI) 95%, 1.26 to 1.39; P < 0.001; pooled effect size for loneliness, 1.14; 95% CI, 1.08 to 1.20; P < 0.001) and cancer mortality (size pooled effect size for social isolation, 1.24, 95% CI, 1.19 to 1.28, P < 0.001; pooled effect size for loneliness, 1.09, 95% CI, 1.01 to 1.17; P = 0.030).
Social isolation also increased the risk of CVD mortality (1.34; 95% CI, 1.25 to 1.44; P < 0.001).
There was an increased risk of all-cause mortality in socially isolated individuals with CVD (1.28; 95% CI, 1.10 to 1.48; P = 0.001) or breast cancer (1.51; 95% CI %, 1.34 to 1.70; P < 0.001), and people with breast cancer had higher cancer-specific mortality due to social isolation (1.33; 95% CI, 1.02 to 1.75 ; P = 0.038).
An increased focus on social isolation and loneliness can help improve people’s well-being and mortality risk.
Reference : Wang, F., Gao, Y., Han, Z. et al. A systematic review and meta-analysis of 90 cohort studies of social isolation, loneliness and mortality. Nat Hum Behav (2023). https://doi.org/10.1038/s41562-023-01617-6
