BACKGROUND: The association of social capital with health and mortality is contentious, and empirical findings are inconsistent. This study tests the association of neighbourhood-level volunteerism with mortality. METHODS: Cohort study of 1996 New Zealand census respondents aged 25-74 years (4.75 million person years) using multilevel Poisson regression analyses. Neighbourhood (average population 2,034) measures included indices of social capital (volunteering activities for all census respondents) and deprivation. RESULTS: Adjusting for just age and marital status, the mortality rate ratios for people living in the quintile of neighbourhoods with the lowest compared with highest volunteerism were 1.16 (95% confidence interval 1.08-1.24) and 1.09 (1.01-1.18), for males and females, respectively. Adjusting for potential individual-level and neighbourhood-level socioeconomic confounders reduced the rate ratios to 0.94 (0.88-1.01) and 0.92 (0.85-1.01), respectively. There was no significant association with any cause of death, including suicide [rate ratios 0.89 (0.64-1.22) and 0.57 (0.31-1.05), respectively]. Restricting the analyses to only those census respondents living at their census night address for five or more years, and therefore 'exposed' to that level of volunteerism for a longer period, did not substantially alter findings. CONCLUSIONS: This study, one of the largest multilevel studies yet, found no statistically significant independent association of a structural measure of neighbourhood social capital with mortality-including suicide. Assuming social features of neighbourhoods are important determinants of health, future research should examine other features (e.g. social fragmentation) and other outcomes (e.g. behaviour).
BACKGROUND: The association of social capital with health and mortality is contentious, and empirical findings are inconsistent. This study tests the association of neighbourhood-level volunteerism with mortality. METHODS: Cohort study of 1996 New Zealand census respondents aged 25-74 years (4.75 million person years) using multilevel Poisson regression analyses. Neighbourhood (average population 2,034) measures included indices of social capital (volunteering activities for all census respondents) and deprivation. RESULTS: Adjusting for just age and marital status, the mortality rate ratios for people living in the quintile of neighbourhoods with the lowest compared with highest volunteerism were 1.16 (95% confidence interval 1.08-1.24) and 1.09 (1.01-1.18), for males and females, respectively. Adjusting for potential individual-level and neighbourhood-level socioeconomic confounders reduced the rate ratios to 0.94 (0.88-1.01) and 0.92 (0.85-1.01), respectively. There was no significant association with any cause of death, including suicide [rate ratios 0.89 (0.64-1.22) and 0.57 (0.31-1.05), respectively]. Restricting the analyses to only those census respondents living at their census night address for five or more years, and therefore 'exposed' to that level of volunteerism for a longer period, did not substantially alter findings. CONCLUSIONS: This study, one of the largest multilevel studies yet, found no statistically significant independent association of a structural measure of neighbourhood social capital with mortality-including suicide. Assuming social features of neighbourhoods are important determinants of health, future research should examine other features (e.g. social fragmentation) and other outcomes (e.g. behaviour).
Authors: Jun Aida; Katsunori Kondo; Hiroshi Hirai; S V Subramanian; Chiyoe Murata; Naoki Kondo; Yukinobu Ichida; Kokoro Shirai; Ken Osaka Journal: BMC Public Health Date: 2011-06-25 Impact factor: 3.295
Authors: Tuula Oksanen; Mika Kivimäki; Ichiro Kawachi; S V Subramanian; Soshi Takao; Etsuji Suzuki; Anne Kouvonen; Jaana Pentti; Paula Salo; Marianna Virtanen; Jussi Vahtera Journal: Am J Public Health Date: 2011-07-21 Impact factor: 9.308