@article {Crowe2020.07.10.20147488,
	title = {Associations of Loneliness and Social Isolation with Health Span and Life Span in the US Health and Retirement Study},
	journal = {The Journals of Gerontology: Series A },
	volume = {76},
	year = {2021},
	pages = {1997-2006},
	abstract = {Background Loneliness and social isolation are emerging public health challenges for aging populations.Methods We followed N=11,302 US Health and Retirement Study (HRS) participants aged 50-95 from 2006-2014 to measure persistence of experiences of loneliness and exposure to 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, with 6\% meeting criteria at two or more follow-up assessments. For social isolation, these fractions were 21\% and 8\%. HRS participants who experienced loneliness and were exposed to social isolation were at increased risk for disease, disability, and mortality. Those experiencing persistent loneliness were at a 57\% increased hazard of mortality compared to those who never experienced loneliness. 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 were exposed to social isolation also exhibited physiological indications of advanced biological aging (Cohen{\textquoteright}s-d for persistent loneliness and social isolation=0.26 and 0.21, respectively). For loneliness, but not social isolation, persistence was associated with increased risk.Conclusion Deficits in social connectedness prevalent in a national sample of US older adults were associated with morbidity, disability, and mortality and with more advanced biological aging. Bolstering social connectedness to interrupt experiences of loneliness may promote healthy aging.Competing Interest StatementThe authors have declared no competing interest.Funding StatementThis research was supported by the Robert N Butler Columbia Aging Center, Russel Sage Foundation (grant 1810-08987), and the Jacobs Foundation. CLC is supported by a fellowship from the National Institute of Mental Health (5T32MH013043).Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:The Columbia University Irving Medical Center IRB approved this research.All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesAll data are publicly available on the Health and Retirement Study (HRS) website.},
	keywords = {Healthspan, Loneliness, social isolation},
	doi = {10.1093/gerona/glab128},
	author = {Crowe, CL and Benjamin W Domingue and Hu, G and Keyes, KM and Kwon, Dy and Daniel W. Belsky}
}
