Background. Loneliness and social isolation are emerging public health challenges for aging populations.
Methods. We followed N=11,305 US Health and Retirement Study (HRS) participants aged 50-95 from 2006-2014 to measure persistence of exposure to loneliness and social isolation. We tested associations of longitudinal loneliness and social-isolation phenotypes with disability, morbidity, mortality, and biological aging through 2018.
Results. During follow-up, 18% of older adults met criteria for loneliness and, for 6%, symptoms persisted across two or more follow-up assessments. For social isolation, these fractions were 21% and 8%. HRS participants who experienced loneliness and social isolation were at increased risk for disease, disability, and mortality. Older adults experiencing persistent loneliness were at a 59% increased hazard of mortality compared to those who were never lonely. For social isolation, the increase was 28%. Effect-sizes were somewhat larger for counts of prevalent activity limitations and somewhat smaller for counts of prevalent chronic diseases. Covariate adjustment for socioeconomic and psychological risks attenuated but did not fully explain associations. Older adults who experienced loneliness and social isolation also exhibited physiological indications of advanced biological aging (Cohen's-d for persistent loneliness and social isolation=0.26 and 0.21, respectively). For loneliness, but not social isolation, persistence of symptoms was associated with increased risk.
Conclusion. Deficits in social connectedness prevalent in a national sample of older adults in the US were associated with morbidity, disability, and mortality and with more advanced biological aging. Bolstering social connection to interrupt experiences of loneliness may promote healthy aging.
Spousal Concordance in Telomere Length: New Evidence from Older Adults in the US