Bonding versus bridging social capital and their associations with self rated health: a multilevel analysis of 40 US communities

Study objective: Few studies have distinguished between the effects of different forms of social capital on health. This study distinguished between the health effects of summary measures tapping into the constructs of community bonding and community bridging social capital. Design: A multilevel logistic regression analysis of community bonding and community bridging social capital in relation to individual self rated fair/poor health. Setting: 40 US communities. Participants: Within community samples of adults (n = 24 835), surveyed by telephone in 2000 - 2001. Main results: Adjusting for community sociodemographic and socioeconomic composition and community level income and age, the odds ratio of reporting fair or poor health was lower for each 1-standard deviation (SD) higher community bonding social capital (OR = 0.86; 95% = 0.80 to 0.92) and each 1-SD higher community bridging social capital (OR = 0.95; 95% CI = 0.88 to 1.02). The addition of indicators for individual level bonding and bridging social capital and social trust slightly attenuated the associations for community bonding social capital (OR = 0.90, 95% CI = 0.84 to 0.97) and community bridging social capital (OR = 0.96, 95% CI = 0.89 to 1.03). Individual level high formal bonding social capital, trust in members of one's race/ethnicity, and generalised social trust were each significantly and inversely related to fair/poor health. Furthermore, significant cross level interactions of community social capital with individual race/ethnicity were seen, including weaker inverse associations between community bonding social capital and fair/poor health among black persons compared with white persons. Conclusions: These results suggest modest protective effects of community bonding and community bridging social capital on health. Interventions and policies that leverage community bonding and bridging social capital might serve as means of population health improvement.