Abstract
Objectives
Growing literature demonstrates widening socio-economic gradients in cancer incidence in different countries. However, few studies have measured the magnitude of socio-economic inequalities in the incidence of different types of cancers. This study aimed to evaluate socio-economic inequalities in bladder cancer incidence in Canada over time.
Methods
Using data obtained from the Canadian Cancer Registry (CCR), the Canadian Census of Population (CCP), and the National Household Survey (NHS), we examined socio-economic inequalities of bladder cancer incidence among men and women in Canada from 1992 to 2010. Income- and education-related inequalities were measured using the concentration index (C) approach. We also analyzed the trends of income- and education-related inequalities over the study period.
Results
There is an increasing trend in bladder cancer incidence in Canada. The estimated C suggested a higher incidence of bladder cancer among low socio-economic-status individuals. The results revealed that income-related inequality in bladder cancer incidence increased among the female population. Education-related inequality in the incidence of bladder cancer widened for both males and females in Canada.
Conclusion
The concentration of bladder cancer in Canada is growing among the socio-economically disadvantaged population. Further studies are required to help elucidate causal relationships between socio-economic status and bladder cancer incidence in Canada.
Résumé
Objectifs
L’élargissement des gradients socioéconomiques de l’incidence du cancer dans différents pays est de plus en plus attesté dans la littérature scientifique. Peu d’études ont toutefois mesuré l’ampleur des inégalités socioéconomiques dans l’incidence de différents types de cancers. Nous avons cherché à évaluer les inégalités socioéconomiques dans l’incidence du cancer de la vessie au Canada au fil du temps.
Méthode
À l’aide des données du Registre canadien du cancer (RCC), du Recensement de la population canadienne (RPC) et de l’Enquête nationale auprès des ménages (ENM), nous avons examiné les inégalités socioéconomiques de l’incidence du cancer de la vessie chez les hommes et les femmes au Canada de 1992 à 2010. Nous avons mesuré les inégalités liées au revenu et au niveau d’instruction par la méthode de l’indice de concentration (C). Nous avons également analysé les tendances des inégalités liées au revenu et au niveau d’instruction sur la période de l’étude.
Résultats
L’incidence du cancer de la vessie est en hausse au Canada. L’indice C estimatif indique une incidence supérieure du cancer de la vessie chez les personnes de faible statut socioéconomique. Selon les résultats que nous avons obtenus, les inégalités liées au revenu dans l’incidence du cancer de la vessie ont augmenté dans la population féminine. Les inégalités liées au niveau d’instruction dans l’incidence du cancer de la vessie se sont creusées chez les hommes et les femmes au Canada.
Conclusion
La concentration des cancers de la vessie au Canada s’accentue dans les populations défavorisées sur le plan socioéconomique. Il faudrait pousser la recherche pour élucider les relations causales entre le statut socioéconomique et l’incidence du cancer de la vessie au pays.
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Acknowledgements
Ryan Densmore was a recipient of a Research in Medicine (RIM) studentship funding from the Faculty of Medicine Patrick Madore Memorial Student Fund. Mohammad Hajizadeh acknowledges a Research Development Grant from the Faculty of Health at Dalhousie University to conduct this study. The analyses for this paper were conducted at Statistics Canada’s Atlantic Research Data Centre (ARDC) at Dalhousie University, which is part of the Canadian Research Data Centre Network (CRDCN). We would like to thank CRDCN for facilitating the access to data, and ARDC analyst Heather Hobson for her support and assistance.
Funding
This research was conducted with the support of the Dalhousie Medical Research Foundation Cresco Studentship and a Research Development Grant from the Faculty of Health at Dalhousie University.
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The data for this study were accessed through Statistics Canada’s Research Data Centre (RDC). Statistics Canada has put in place strict disclosure practices which the RDC closely obeys, allowing their approved project to be exempt from research ethics board review based on Tri-council policy statement: Ethical conduct for research involving humans (TCPS2) article 2.2 (a).
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Densmore, R., Hajizadeh, M. & Hu, M. Trends in socio-economic inequalities in bladder cancer incidence in Canada: 1992–2010. Can J Public Health 110, 722–731 (2019). https://doi.org/10.17269/s41997-019-00227-y
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DOI: https://doi.org/10.17269/s41997-019-00227-y