Social Isolation and Adult Mortality: The Role of Chronic Inflammation and Sex Differences.

1Department of Sociology, Lineberger Comprehensive Cancer Center, and Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Journal of Health and Social Behavior (Impact Factor: 2.72). 05/2013; DOI: 10.1177/0022146513485244
Source: PubMed

ABSTRACT The health and survival benefits of social embeddedness have been widely documented across social species, but the underlying biophysiological mechanisms have not been elucidated in the general population. The authors assessed the process by which social isolation increases the risk for all-cause and chronic disease mortality through proinflammatory mechanisms. Using the 18-year mortality follow-up data (n = 6,729) from the National Health and Nutrition Examination Survey (1988-2006) on Social Network Index and multiple markers of chronic inflammation, the authors conducted survival analyses and found evidence that supports the mediation role of chronic inflammation in the link between social isolation and mortality. A high-risk fibrinogen level and cumulative inflammation burden may be particularly important in this link. There are notable sex differences in the mortality effects of social isolation in that they are greater for men and can be attributed in part to their heightened inflammatory responses.

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