Social Isolation, Chronic Inflammation, and Adult Mortality

Yang Yang, University of North Carolina at Chapel Hill
Martha McClintock, University of Chicago
Michael Kozloski, University of Chicago

Health and survival benefits of social embeddedness have been widely documented across social species, but the underlying biophysiological mechanisms have yet to be fully elucidated. This study assessed the process through which social isolation increases the risk of all-cause and chronic disease mortality through inflammatory responses. Using the 18-year mortality follow-up data from the National Health and Nutrition Examination Survey (1988–2006), we conducted survival analyses and found evidence that supports the mediation role of inflammation in the social isolation-mortality link. We also found sex and age differences in this relationship. The mortality effects of social isolation are greater for older males and can be attributed in part to their heightened inflammatory responses to social isolation. A high risk fibrinogen level may be particularly important in such responses. Our findings are similar for circulatory disease mortality in older adults and for cancer mortality in middle-aged males.