Abstract
OBJECTIVE: To quantify the extent to which income and education explain gradients in oral health outcomes.
METHODS: Using data from the Canadian Community Health Survey (CCHS 2003), binary logistic regression models were constructed to examine the relationship between income and education on self-reported oral health (SROH) and chewing difficulties (CD) while controlling for age, sex, ethnicity, employment status and dental insurance coverage. The relative index of inequality (RII) was utilized to quantify the extent to which income and education explain gradients in poor SROH and CD.
RESULTS: Income and education gradients were present for SROH and CD. From fully adjusted models, income inequalities were greater for CD (RIIinc = 2.85) than for SROH (RIIinc = 2.75), with no substantial difference in education inequalities between the two. Income explained 37.4% and 42.4% of the education gradient in SROH and CD respectively, whereas education explained 45.2% and 6.1% of income gradients in SROH and CD respectively. Education appears to play a larger role than income when explaining inequalities in SROH; however, it is the opposite for CD.
CONCLUSION: In this sample of the Canadian adult population, income explained over one third of the education gradient in SROH and CDs, whereas the contribution of education to income gradients varied by choice of self-reported outcome. Results call for stakeholders to improve affordability of dental care in order to reduce inequalities in the Canadian population.
Key Words: Oral health, socio-economic factors, educational status, income, population health
Résumé
OBJECTIF: Chiffrer la mesure dans laquelle le revenu et l’instruction expliquent les gradients dans les résultats de santé buccodentaire.
MÉTHODE: À l’aide des données de l’Enquête sur la santé dans les collectivités canadiennes (ESCC, 2003), nous avons construit des modèles de régression logistique pour examiner la relation entre le revenu, d’une part, et l’instruction, d’autre part, sur la santé buccodentaire autodéclarée (SBA) et sur les difficultés de mastication (DM), en tenant compte des effets de l’âge, du sexe, de l’ethnicité, de la situation d’emploi et de l’assurancesoins dentaires. Nous avons utilisé l’indice relatif d’inégalité (IRI) pour chiffrer la mesure dans laquelle le revenu et l’instruction expliquent les gradients des problèmes de SBA et des DM.
RÉSULTATS: Les gradients du revenu et de l’instruction étaient présents tant pour la SBA que pour les DM. Selon les modèles pleinement ajustés, les inégalités de revenu étaient plus prononcées pour les DM (IRIrev = 2,85) que pour la SBA (IRIrev = 2,75), mais il n’y avait pas de différence marquée dans les inégalités en matière d’instruction. Le revenu expliquait 37,4 % et 42,4 % du gradient de l’instruction pour la SBA et les DM, respectivement, tandis que l’instruction expliquait 45,2 % et 6,1 % du gradient du revenu pour la SBA et les DM, respectivement. L’instruction semble jouer un plus grand rôle que le revenu lorsqu’il s’agit d’expliquer les inégalités de SBA; c’est toutefois le contraire pour les DM.
CONCLUSION: Dans cet échantillon de la population adulte canadienne, le revenu a expliqué plus du tiers du gradient de l’instruction pour la santé buccodentaire autodéclarée et pour les difficultés de mastication, tandis que l’apport de l’instruction dans les gradients du revenu variait selon le choix du résultat autodéclaré. Ces résultats appellent les acteurs du milieu à améliorer l’abordabilité des soins dentaires pour réduire les inégalités dans la population canadienne.
Mots Clés: santé buccodentaire, facteurs socioéconomiques, niveau d’instruction, revenu, santé des populations
Footnotes
Conflict of Interest: None to declare.
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