Geographical Epidemiology of Health and Deprivation: a Population-Based, Spatio-Temporal Analysis of Health and Social Inequality in Nova Scotia, Canada

Abstract

Narrowing the gap in health inequality is vital not only from an equity point of view but also from an economic cost point of view. Small-area level investigations of health inequalities can play an important role in this effort. This research is an attempt to produce evidence of within-province social and health inequality. This cross-sectional, ecological study examines the geographical distribution of life expectancy at birth (LE) and its relationships with two domains of deprivation—material and social—at two time periods (1995-1999 and 2003-2007) across 182 ‘communities.’ The deprivation measures were derived from a set of indices now widely used in Quebec. Five community types assigned to the communities represented relative levels of rurality. A general pattern was observed that material deprivation became more prominent as ‘rurality’ increased. The pattern of social deprivation by rurality was more ‘flat’ where other levels of rurality than the most urban type had similar deprivation scores and rankings. LE was patterned by a relative degree of deprivation but not by rurality per se, though high socioeconomic deprivation tends to be observed in ‘rural areas.’ The gaps in LEs between the most and least deprived were wider for males than for females. Inequalities in LE by material deprivation of the communities appear to have widened over time. The regression models indicated the presence of an interaction effect—material and social deprivation together exacerbate the risk of low LE. The study also observed some regional clustering of unaccounted factors, which requires further investigation to determine what potential regional phenomena account for this effect. Lastly, the deprivation scores left more variations in LE in rural communities unexplained than variations in urban communities, leading us to suspect that the indices employed might be less sensitive for health inequalities in rural communities than in urban communities. Further research efforts are necessary to tackle many questions this research could not address, which would more fully inform policy related to the reduction of health and social inequality in Nova Scotia and elsewhere.