Health inequalities associated with neighbourhood deprivation in the Quebec population with hypertension in primary prevention of cardiovascular disease.

INTRODUCTION: Although a number of studies look at prevalence, incidence, treatment, mortality and morbidity in relation to hypertension, few have taken into account the effect of residential neighbourhood on these health indicators in the population diagnosed with hypertension.

OBJECTIVES: The objective of this study was to measure and compare prevalence, mortality, morbidity, use of medical resources and treatments in relation to the level of material and social deprivation of the area of residence, in a population with a diagnosis of hypertension in primary prevention for cardiovascular disease (CVD) in Quebec in 2006-2007.

METHODS: This study is based on a secondary analysis of the medical administrative data of the Quebec health insurance board, the Régie de l'assurance maladie du Québec, for a cohort of 276 793 patients aged 30 years or older who had been diagnosed with hypertension in 2006 or 2007, but who did not have a known diagnosis of CVD. The health indicators adjusted for age and sex are prevalence, death, a cardiovascular event, physician visits, emergency department visits and use of antihypertensives. Twenty-five types of areas of residence were obtained by crossing the material and social deprivation quintiles.

RESULTS: Compared with patients living in materially and socially advantaged areas, those living in deprived areas were at 46% higher risk of a cardiovascular event, 47% higher risk of being frequent emergency department visitors and 31% higher risk of being frequent users of a general practitioner's services, but 25% lower risk of being frequent users of medical specialists' services. Little or no variation was observed in the use of antihypertensives.

CONCLUSION: This study reveals the existence, in a CVD primary prevention context, of large variations in a number of health indicators among hypertensive patients owing to the material and social deprivation of residential neighbourhood. It is therefore important to take the socioeconomic context into account when planning interventions to prevent CVDs and their consequences.