Abstract
Objectives
The aim of this study was to measure and compare the magnitude of income-related inequalities for oral and general health outcomes in Canada.
Methods
Data for this study were from the 2007/09 Canadian Health Measures Survey (CHMS). The sample size consisted of 3,413 Canadians aged 18–79 (1,601 men and 1,812 women). Oral health indicators were the total number of decayed and missing teeth. General health was measured as obesity and high blood pressure. Socio-economic status was measured as equivalized household income. We used the concentration index (CI) to quantify income-related inequalities in these outcomes. Values for the concentration index range from -1 to +1 with negative (or positive) concentration indices showing that the outcome is more concentrated among the less well off (or among the better off). All statistical analyses were weight-adjusted for the complex survey design and standardized for age.
Results
The concentration indices for oral health outcomes (decayed teeth = −0.25, missing teeth = −0.15) were greater than for general health outcomes (obesity = −0.05, high blood pressure = −0.04). The concentration indices for oral health outcomes, in contrast to general health outcomes, were statistically significant.
Conclusion
There were income-related inequalities for oral health outcomes with the disease concentrated more among the poor. Inequalities in oral health were greater than inequalities in general health. The variation in the funding of oral health care and general health care is likely to explain the differences in the magnitude of income-related inequalities for oral and general health.
Key words: Socioeconomic factors, oral health, income, obesity, blood pressure
Résumé
Objectifs
Mesurer et comparer l’ampleur des inégalités liées au revenu pour ce qui est des résultats de santé buccodentaire et de santé générale au Canada.
Méthode
Les données de l’étude proviennent de l’Enquête canadienne sur les mesures de la santé (ECMS) de 2007–2009. L’échantillon englobait 3 413 Canadiens de 18 à 79 ans (1 601 hommes et 1 812 femmes). Les indicateurs de la santé buccodentaire étaient le nombre total de dents cariées et manquantes. La santé générale a été mesurée selon l’obésité et l’hypertension artérielle. Le statut socioéconomique a été mesuré selon le revenu équivalent des ménages. Nous avons utilisé l’indice de concentration (IC) pour chiffrer les inégalités liées au revenu dans les résultats obtenus. La valeur de l’indice de concentration variait de −1 à +1, les indices négatifs (ou positifs) montrant que le résultat était plus concentré dans les populations plus démunies (ou plus aisées). Les analyses statistiques ont été pondérées en fonction de la complexité de l’enquête et standardisées selon l’âge.
Résultats
Les indices de concentration des résultats de santé buccodentaire (dents cariées = −0,25, dents manquantes = −0,15) étaient supérieurs à ceux des résultats de santé générale (obésité = −0,05, hypertension artérielle = −0,04). Les indices de concentration des résultats de santé buccodentaire, contrairement aux résultats de santé générale, étaient statistiquement significatifs.
Conclusion
Il y avait des inégalités liées au revenu pour les résultats de santé buccodentaire, la maladie étant davantage concentrée chez les pauvres. Les inégalités de santé buccodentaire étaient plus prononcées que les inégalités de santé générale. L’écart entre le financement des soins de santé buccodentaires et les soins de santé généraux explique probablement les différences dans l’ampleur des inégalités liées au revenu pour ce qui est de la santé buccodentaire et de la santé générale.
Mots clés: facteurs socioéconomiques, santé buccodentaire, revenu, obésité, pression artérielle
Footnotes
Acknowledgements: This research was funded in part by the Association of Canadian Faculties of Dentistry, the Canadian Association for Dental Research, the Institute for Musculoskeletal Health and Arthritis, the Nova Scotia Health Research Foundation, the Order of Dentists of Quebec and the Network for Oral and Bone Health Research. Access to data from the 2007–2009 Canadian Health Measures Survey was obtained through Statistics Canada at McGill University.
Conflict of Interest: None to declare.
References
- 1.US Department of HealthHuman Services. Oral Health in America: A Report of the Surgeon General. Rockville, MD: US Department of Health and Human Services, National Institutes of Health, National Institute of Dental and Craniofacial Research; 2000. [Google Scholar]
- 2.Stamm J, Waller M, Lewis D, Stoddart G. Dental Care Programs in Canada: Historical Development, Current Status, and Future Directions—A Report Prepared on Contract for the Department of National Health and Welfare, Canada. Ottawa, ON: Canadian Government Publishing Centre; 1986. [Google Scholar]
- 3.Locker D, Maggirias J, Quinonez C. Income, dental insurance coverage, and financial barriers to dental care among Canadian adults. J Public Health Dentistry. 2011;71(4):327–34. doi: 10.1111/j.1752-7325.2011.00277.x. [DOI] [PubMed] [Google Scholar]
- 4.Report on the Findings of the Oral Health Component of the Canadian Health Measures Survey 2007–2009. Available at: https://doi.org/www.hc-sc.gc.ca/ahc-asc/branch-dirgen/fnihb-dgspni/ocdo-bdc/project-eng.php (Accessed January 1, 2014).
- 5.Allin S. Does equity in healthcare use vary across Canadian provinces? Healthc Policy. 2008;3(4):83–99. [PMC free article] [PubMed] [Google Scholar]
- 6.Statistics Canada. Canadian Health Measures Survey (CHMS). Available at: https://doi.org/www.statcan.gc.ca/cgi-in/imdb/p2SV.pl?Function=getSurvey&SDDS=5071&lang=en&db= imdb&adm=8&dis=2 (Accessed January 1, 2014).
- 7.Mathers C, Stevens G, Mascarenhas M. Global Health Risks: Mortality and Burden of Disease Attributable to Selected Major Risks. Geneva, Switzerland: World Health Organization; 2009. [Google Scholar]
- 8.World Health Organization. Global Database on Body Mass Index: An Interactive Surveillance Tool for Monitoring Nutrition Transition. 2014. [Google Scholar]
- 9.Organisation for Economic Co-operationDevelopment. What Are Equivalence Scales? 2010. [Google Scholar]
- 10.Mackenbach JP, Kunst AE. Measuring the magnitude of socio-economic inequalities in health: An overview of available measures illustrated with two examples from Europe. Soc Sci Med. 1997;44(6):757–71. doi: 10.1016/S0277-9536(96)00073-1. [DOI] [PubMed] [Google Scholar]
- 11.Wagstaff A, Paci P, Vandoorslaer E. On the measurement of inequalities in health. Soc Sci Med. 1991;33(5):545–57. doi: 10.1016/0277-9536(91)90212-U. [DOI] [PubMed] [Google Scholar]
- 12.Wagstaff A. The bounds of the concentration index when the variable of interest is binary, with an application to immunization inequality. Health Econ. 2005;14(4):429–32. doi: 10.1002/hec.953. [DOI] [PubMed] [Google Scholar]
- 13.Ravaghi V Q C, Allison JP. The magnitude of oral health inequalities in Canada: Findings of the Canadian Health Measures Survey. Community Dent Oral Epidemiol. 2013;41(6):490–98. doi: 10.1111/cdoe.12043. [DOI] [PubMed] [Google Scholar]
- 14.Chaplin R, Earl L. Household spending on health care. Health Rep. 2000;12(1):57–65. [PubMed] [Google Scholar]
- 15.Mackenbach JP. An analysis of the role of health care in reducing socioeconomic inequalities in health: The case of the Netherlands. Int J Health Serv. 2003;33(3):523–41. doi: 10.2190/C12H-NBA4-7QWE-6K3T. [DOI] [PubMed] [Google Scholar]
- 16.Gelormino E, Bambra C, Spadea T, Bellini S, Costa G. The effects of health care reforms on health inequalities: A review and analysis of the European evidence base. Int J Health Serv. 2011;41(2):209–30. doi: 10.2190/HS.41.2.b. [DOI] [PubMed] [Google Scholar]
- 17.Ross NA, Wolfson MC, Dunn JR, Berthelot JM, Kaplan GA, Lynch JM. Relation between income inequality and mortality in Canada and in the United States: Cross sectional assessment using census data and vital statistics. Br Med J. 2000;320(7239):898–902. doi: 10.1136/bmj.320.7239.898. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Huguet N, Kaplan MS, Feeny D. Socioeconomic status and health-related quality of life among elderly people: Results from the Joint Canada/United States Survey of Health. Soc Sci Med. 2008;66(4):803–10. doi: 10.1016/j.socscimed.2007.11.011. [DOI] [PubMed] [Google Scholar]
- 19.McGrail KM, van Doorslaer E, Ross NA, Sanmartin C. Income-related health inequalities in Canada and the United States: A decomposition analysis. Am J Public Health. 2009;99(10):1856–63. doi: 10.2105/AJPH.2007.129361. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Wamala S, Merlo J, Bostrom G. Inequity in access to dental care services explains current socioeconomic disparities in oral health: The Swedish National Surveys of Public Health 2004–2005. J Epidemiol Community Health. 2006;60(12):1027–33. doi: 10.1136/jech.2006.046896. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Somkotra T, Detsomboonrat P. Is there equity in oral healthcare utilization: Experience after achieving Universal Coverage. Community Dent Oral Epidemiol. 2009;37(1):85–96. doi: 10.1111/j.1600-0528.2008.00449.x. [DOI] [PubMed] [Google Scholar]
- 22.Donaldson AN, Everitt B, Newton T, Steele J, Sherriff M, Bower E. The effects of social class and dental attendance on oral health. J Dent Res. 2008;87(1):60–64. doi: 10.1177/154405910808700110. [DOI] [PubMed] [Google Scholar]
- 23.Ravaghi V, Underwood M, Marinho V, Eldridge S. Socioeconomic status and self-reported oral health in Iranian adolescents: The role of selected oral health behaviors and psychological factors. J Public Health Dent. 2012;72(3):198–207. doi: 10.1111/j.1752-7325.2012.00330.x. [DOI] [PubMed] [Google Scholar]
- 24.Harper S, Lynch J. Commentary: Using innovative inequality measures in epidemiology. Int J Epidemiol. 2007;36(4):926–28. doi: 10.1093/ije/dym139. [DOI] [PubMed] [Google Scholar]
- 25.Kaplan MS, Huguet N, Feeny DH, McFarland BH. Self-reported hypertension prevalence and income among older adults in Canada and the United States. Soc Sci Med. 2010;70(6):844–49. doi: 10.1016/j.socscimed.2009.11.019. [DOI] [PubMed] [Google Scholar]
- 26.Godley J, McLaren L. Socioeconomic status and body mass index in Canada: Exploring measures and mechanisms. Can Rev Sociol. 2010;47(4):381–403. doi: 10.1111/j.1755-618X.2010.01244.x. [DOI] [PubMed] [Google Scholar]
- 27.Shields M, Tjepkema M. Trends in adult obesity. Health Rep. 2006;17(3):53–59. [PubMed] [Google Scholar]
- 28.McLaren L, Auld MC, Godley J, Still D, Gauvin L. Examining the association between socioeconomic position and body mass index in 1978 and 2005 among Canadian working-age women and men. Int J Public Health. 2010;55(3):193–200. doi: 10.1007/s00038-009-0085-z. [DOI] [PubMed] [Google Scholar]
- 29.McLaren L. Socioeconomic status and obesity. Epidemiologic Rev. 2007;29:29–48. doi: 10.1093/epirev/mxm001. [DOI] [PubMed] [Google Scholar]
- 30.Sabbah W, Tsakos G, Chandola T, Sheiham A, Watt RG. Social gradients in oral and general health. J Dent Res. 2007;86(10):992–96. doi: 10.1177/154405910708601014. [DOI] [PubMed] [Google Scholar]
- 31.Elani HW, Harper S, Allison PJ, Bedos C, Kaufman JS. Socio-economic inequalities and oral health in Canada and the United States. J Dent Res. 2012;91(9):865–70. doi: 10.1177/0022034512455062. [DOI] [PubMed] [Google Scholar]
- 32.Quinonez CR, Figueiredo R, Locker D. Canadian dentists’ opinions on publicly financed dental care. J Public Health Dentistry. 2009;69(2):64–73. doi: 10.1111/j.1752-7325.2008.00102.x. [DOI] [PubMed] [Google Scholar]
- 33.Sehgal AR. Universal health care as a health disparity intervention. Ann Intern Med. 2009;150(8):561–62. doi: 10.7326/0003-4819-150-8-200904210-00011. [DOI] [PubMed] [Google Scholar]