The Contribution of Neighbourhood Material and Social Deprivation to Survival: A 22-Year Follow-up of More than 500,000 Canadians

BACKGROUND We examined the incremental influence on survival of neighbourhood material and social deprivation while accounting for individual level socioeconomic status in a large population-based cohort of Canadians. METHODS More than 500,000 adults were followed for 22 years between 1982 and 2004. Tax records provided information on sex, income, marital status and postal code while a linkage was used to determine vital status. Cox models were used to estimate hazard ratios (HR) for quintiles of neighbourhood material and social deprivation. RESULTS There were 180,000 deaths over the follow-up period. In unadjusted analyses, those living in the most materially deprived neighbourhoods had elevated risks of mortality (HR(males) 1.37, 95% CI: 1.33-1.41; HR(females) 1.20, 95% CI: 1.16-1.24) when compared with those living in the least deprived neighbourhoods. Mortality risk was also elevated for those living in socially deprived neighbourhoods (HR(males) 1.15, CI: 1.12-1.18; HR(females) 1.15, CI: 1.12-1.19). Mortality risk associated with material deprivation remained elevated in models that adjusted for individual factors (HR(males) 1.20, CI: 1.17-1.24; HR(females) 1.16, CI: 1.13-1.20) and this was also the case for social deprivation (HR(males) 1.12, CI: 1.09-1.15; HR(females) 1.09, CI: 1.05-1.12). Immigrant neighbourhoods were protective of mortality risk for both sexes. Being poor and living in the most socially advantageous neighbourhoods translated into a survival gap of 10% over those in the most socially deprived neighbourhoods. The gap for material neighbourhood deprivation was 7%. CONCLUSIONS Living in socially and materially deprived Canadian neighbourhoods was associated with elevated mortality risk while we noted a "healthy immigrant neighbourhood effect". For those with low family incomes, living in socially and materially deprived areas negatively affected survival beyond their individual circumstances.