Abstract
Objective
To examine the association of income inequality at the public health unit level with individual health status in Ontario.
Methods
Cross-sectional multilevel study carried out among subjects aged 25 years or older residing in 42 public health units in Ontario. Individual-level data drawn from 30,939 respondents in 1996–97 Ontario Health Survey. Median area income and income inequality (Gini coefficient) calculated from 1996 census. Self-rated health status (SRH) and Health Utilities Index (HUI-3) scores were used as main outcomes.
Results
Controlling for individual-level factors including income, respondents living in public health units in the highest tercile of income inequality had odds ratios of 1.20 (95% CI 1.04–1.38) for fair/poor self-rated health, and 1.11 (95% CI 1.01–1.22) for HUI score below the median, compared with people living in public health units in the lowest tercile. Controlling further for median area income had little effect on the association.
Conclusion
Income inequality was significantly associated with individual self-reported health status at public health unit level in Ontario, independent of individual income.
MeSH terms: Income distribution, Health Status Index
Résmé
Objectif
Examiner l’association entre l’inégalité des revenus à l’échelle des unités de santé publique et l’état de santé individuel en Ontario.
Méthode
Étude transversale multiniveau effectuée auprès de sujets de 25 ans et plus desservis par les 42 bureaux de santé publique de l’Ontario. Les données individuelles provenaient des réponses de 30 939 répondants à l’Enquête sur la santé en Ontario (1996–1997). Le revenu médian par zone et l’inégalité des revenus (coefficient de Gini) ont été calculés d’après les données du recensement de 1996. Les principaux résultats que nous avons utilisés ont été les scores obtenus aux chapitres de l’état de santé auto-évalué (ESAE) et du Health Utilities Index (HUI-3).
Résultats
Après les ajustements pour tenir compte des effets de facteurs individuels, dont le revenu, les répondants desservis par les bureaux de santé publique dans le tercile supérieur de l’inégalité des revenus présentaient un risque relatif de 1,20 (IC de 95 % = 1,04–1,38) pour un ESAE moyen ou mauvais, et un risque relatif de 1,11 (IC de 95 % = 1,01–1,22) pour un HUI inférieur à la médiane, par rapport aux personnes desservies par les bureaux de santé publique dans le tercile inférieur. L’apport d’autres ajustements pour tenir compte des effets du revenu médian de la zone a peu modifié cette association.
Conclusion
L’inégalité des revenus présente une corrélation significative avec l’état de santé auto-évalué à l’échelle des bureaux de santé publique en Ontario, quel que soit le revenu personnel.
Footnotes
Acknowledgements and sources of support: Guoliang Xi acknowledges financial support from the University of Ottawa and the Health Information Partnership, Eastern Ontario Region (HIP). The authors also thank Ms. Nam Bains (Director of HIP) for her invaluable assistance.
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