Health disparities by neighborhood socioeconomic status and the role of spatial spillovers

Abstract

Abstract Background The contextual determinants of population health disparities across neighborhoods with similar socioeconomic characteristics are not well understood. We aimed to estimate subjective and objective population health measures within and between neighborhoods with similar socioeconomic status (NSES) scores, and the (in)direct potential of a spillover effect of NSES of adjacent neighborhoods. Methods Based on whole-population neighborhood data we determined the percentage of inhabitants with good/very good self-assessed health (SAH) and with at least one chronic disease (CD) in 11,521 neighborhoods with on average 1,470 inhabitants. Neighborhoods were classified by the quintile of a composite NSES score. Spatial lag of X models was applied by including neighborhood cross-sectional units on population density, the percentage of inhabitants aged 65 and over, and the NSES of adjacent neighborhoods by constructing a spatial weights matrix. Results Substantial population health disparities in SAH and CD both between neighborhoods with different and similar NSES scores were observed, with the largest SAH variance in the lowest NSES group. These differences were only partially explained by neighborhood characteristics. Neighborhoods adjacent to higher SES neighborhoods showed a higher SAH and a lower prevalence of CD, adjusted for other explanatory variables. When NSES in the first decile would be increased to the NSES of the quintile median, the direct effect on SAH would increase by 5.6% in the lowest NSES group. Spillovers would lead to an additional increase of 1.7% in all NSES groups. Conclusions Population health differs substantially among neighborhoods with similar socioeconomic characteristics, which can partially be explained by a socioeconomic spillover effect. The mechanisms behind these spillovers need further study, but may already provide interesting leads to policy design aimed at improving population health outcomes of deprived neighborhoods. Key messages Neighborhood population health is partially affected by a SES spillover effect. This study provides interesting leads to policy design aimed at improving health outcomes of deprived neighborhoods.