Recent changes in the geography of social disparities in premature mortality in Québec

Most recent research reveals that social inequalities in premature mortality are widening. Such findings mainly apply to countries as a whole. In this study, we model recent changes in the association between premature mortality and a deprivation index (a small area-based index) in four geographic settings in Québec, namely the Montréal metropolitan area, other Québec metropolitan areas, mid-size cities, and small towns and rural areas. Deaths from all-cause and specific causes of mortality among people under age 75 are considered for the periods 1989-1993 and 1999-2003. Mortality rates are modeled using negative binomial regressions. Models are fitted for the overall population and for men and women, separately, in every geographic setting. Three measures of inequalities are used: mortality rates for different population groups, rate ratios and rate differences. Results show that social inequalities in premature mortality increase everywhere in Québec except in the Montréal metropolitan area. Presently, the highest mortality rates among deprived groups are found in mid-size cities, small towns and rural areas; the highest rate ratios in the Montréal metropolitan area and other metropolitan areas of Québec; and the highest rate differences in the Montréal metropolitan area, other metropolitan areas of Québec and mid-size cities. These results are discussed with reference to possible explanatory factors, namely relative deprivation, smoking, immigration and internal migration. Indications on future research and policy implications are provided.