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; 54(2). DOI: 10.1177/0022146513485244
Source: PubMed


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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Available from: Michael Kozloski, May 11, 2015
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    • "Emerging research also shows that social network characteristics are associated with measures of neural integrity (Yang et al., 2013). For example, neuroimaging studies demonstrate that people with larger and more diverse social networks have larger brain volumes and greater functional connectivity in emotional salience processing networks (Bickart et al., 2011, 2012), while larger social networks are indirectly associated with greater volume in the orbital prefrontal cortex, an area implicated in social cognition (Powell et al., 2012). "
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    • "Interestingly a few studies indicate chronic isolation is associated with a pro-inflammatory gene expression profile, but the nature and direction of the inflammatory response also differs across sex and age (Cole et al., 2010, 2011; Yang et al., 2013). Many evidence has indicated that chronic stressors in general including prolonged social isolation could modulate the activity of HPA and affect immune function and immune performance, which may lead to a variety of health problems including chronic infection, autoimmune disease and the development of other diseases (McEwen, 1998; Reiche et al., 2004; Cohen et al., 2007; Miller et al., 2007; McEwen, 2008; Cohen et al., 2012). "
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    • "The quality of personal and social relationships is clearly linked to chronic disease outcomes [117] including heart disease [118], stroke [119], some cancers [120], and allcause mortality [121]. The pathways for this are, as yet, unclear and psychological mediators have not been proven [122], but inflammatory processes have been associated with poor social relations [123] such as spousal ambivalence [124] and isolation [125] and can even stem back to maternal separation in childhood [126]. People who have supportive close relationships have lower levels of systemic inflammation compared to people who have unsatisfactory relationships [127]. "
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