Social networks and immunosuppression during stress: Relationship conflict or energy conservation?

Abstract

Despite the apparent health benefits of social relationships, some studies indicate that larger social networks can be associated with greater vulnerability to infectious disease, particularly if stressors are also present. Two possibilities for such effects are, first, that more social contacts lead to more negative affect and social conflict during stressors, or second, that maintaining more social contacts is an energetically costly activity, and ecologically motivated immunosuppression is one means of providing energy to maintain social resources. First-year law students (N = 76) completed questionnaires and had delayed-type hypersensitivity skin tests at five time points during their first 6 months of law school. Both moving away from home and a smaller social network associated with larger DTH responses (both p < .05) across all time points. However, negative affect, either broadly defined or as specific affects (hostility, sadness, guilt), did not mediate social network effects, suggesting that negative affect and social conflict are less plausible explanations than ecological immunosuppression. Ecological models would predict that temporary immunosuppression is less harmful to health in the long run than loss of social resources.Social relationships seem to yield significant health benefits, with the mortality risk of a small social network approximately equaling that for cigarette smoking (House et al., 1988). One potential pathway between social connectedness and clinical health is physiological: higher social support is associated with lower tonic blood pressure, reduced cardiovascular reactivity, and higher functional immune assays (e.g., natural killer cell cytotoxicity) and, conversely, loneliness is associated with elevated cortisol and lower functional immune assays (see Cacioppo et al., 2000;Uchino et al., 1996; for reviews). Beneficial effects of social relationships extend to non-human animals. For example, juvenile macaques separated from their mothers had higher lymphocyte proliferative responses if they were housed with conspecifics with whom they had "significant, complex relationships" than if they were housed alone; furthermore, proliferative responses were positively correlated with degree of affiliation with others during the separation (Boccia et al., 1997, p. 193).However, there are some notable cases in which a larger number of social relationships negatively correlated with immunity and health. Miller and Cole (1998) reviewed 10 studies of social relationships and HIV progression. In these studies, loneliness and other measures of low emotional satisfaction with social relationships associated with faster HIV progression. However, larger social network size and other measures of greater social integration such as intent to participate in social activities and greater affinity with social networks also associated with faster progression. An interaction between stress and social connectedness was observed Correspondence to: Suzanne C. Segerstrom, Ph.D., Department of Psycholo...

Personality and risk of adult asthma in a prospective cohort study

“…For example, stress has been associated with increased release of pro-inflammatory neuropeptides by the airway-innervating autonomic nerves [41], with amplification of delayed-type hypersensitivity responses [42], and with increased airway inflammation after allergen exposure [43]. Moreover, immune cells from stressed individuals show a cytokine release profile suggestive of enhanced allergic activity (e.g., Th2-shifted) [44][45][46].…”

Predictors of delayed‐type hypersensitivity to Candida albicans and anti‐epstein‐barr virus antibody among children in Kilimanjaro, Tanzania

“…For example, in the US, most adults are assumed to have competent cell-mediated immune responses, and DTH to tuberculin purified protein derivative (PPD) is used to screen for Mycobacterium tuberculosis exposure (Lee and Holzman, 2002). Conversely, DTH testing with an antigen to which exposure can be assumed, such as the ubiquitous fungal pathogen, Candida albicans , is used to evaluate CMI (e.g., Edelman et al, 1973; Segerstrom, 2008) . C. albicans is the causative agent of “thrush” (oral candidiasis) and “yeast infection” (vaginal candidiasis); among severely immunocompromised individuals, it can cause life-threatening systemic infection (candidemia).…”

Resources, Stress, and Immunity: An Ecological Perspective on Human Psychoneuroimmunology

“…Among first-year law students, relocation to attend law school and attendant separation from established social networks was associated with better cellular immunity as measured by delayed-type hypersensitivity (DTH) testing. Within-person changes in social network size across the first six months of law school paralleled this betweenperson finding: at those assessment points when a student had more social contacts, he or she also had poorer cellular immunity [9]. Although there might be a psychological benefit to tonic and phasic engagement with one's social network, there also appears to be an immunological cost associated with maintaining network contacts while also meeting the demands of law school.…”

“…There are, however, some unusual and perplexing findings with regard to the effects of social networks on immune function. Larger social networks have associated with poorer cellular immunity in healthy young adults and HIV patients [8,9]. One study found that the increased risk of upper respiratory infection that accompanies severe life stressors increased further for those people with large social networks [10].…”