Abstract
Objective
The objective of this paper is to examine spatial patterns of asthma prevalence in the province of Ontario by age and sex between 2002 and 2006.
Methods
We conducted a population-based, ecological-level study using the Ontario Asthma Surveillance Information System Database (OASIS), a validated registry of all Ontario residents with asthma. Data were mapped and analyzed at the sub-Local Health Integration Network (subLHIN) level (n=141). Comparative morbidity figures (CMFs) were calculated and analyzed for local clusters of high and low values (“hot spots” and “cold spots”).
Results
There were 1,601,353 individuals identified as having asthma over the study period, representing an overall prevalence rate of 12.93%. Results demonstrate distinct spatial patterns of asthma prevalence across the province which are age- and sex-specific. There was little overlap between asthma hot spots by age group, suggesting that different spatial processes are at play. Patterns of cold spots are consistently seen in the urban and suburban subLHINs in and around Toronto and Hamilton as well as in several of the highly rural northern subLHINs.
Conclusions
Findings illustrate the need for more geographically focused public health and health care planning and resource allocation, and highlight the need for research aimed at understanding the factors that may explain the spatial patterns identified here.
Key words: Asthma, prevalence, spatial analysis, Ontario
Résumé
Objectif
Examiner les structures spatiales de la prévalence de l’asthme dans la province de l’Ontario, par âge et par sexe, entre 2002 et 2006.
Méthode
Nous avons mené une étude écologique en population à l’aide de la base de données OASIS (Ontario Asthma Surveillance Information System), un registre validé de tous les résidents de l’Ontario atteints d’asthme. Les données ont été mappées et analysées au niveau des sous-réseaux locaux d’intégration des services de santé (sous-RLISS) (n=141). Nous avons calculé et analysé des indices comparatifs de morbidité pour les grappes locales de valeurs élevées et faibles (« points chauds » et « points froids »).
Résultats
Sur la période de l’étude, 1 601 353 personnes ont été identifiées comme faisant de l’asthme, soit un taux de prévalence global de 12,93 %. Les résultats font état de structures spatiales de prévalence de l’asthme distinctes dans la province, ces structures étant propres à l’âge et au sexe. Il y a peu de chevauchements entre les points chauds de l’asthme par groupe d’âge, ce qui pourrait indiquer que différents processus spatiaux sont en cause. Des points froids sont systématiquement observés dans les sous-RLISS urbains et suburbains de la grande région de Toronto et de Hamilton ainsi que dans plusieurs des sous-RLISS très ruraux du nord de la province.
Conclusion
Ces constatations soulignent que la planification et l’attribution des ressources de la santé publique et des soins de santé devraient se faire davantage sur une base géographique; il faudrait pousser la recherche pour comprendre les facteurs pouvant expliquer les structures spatiales cernées ici.
Mots clés: asthme, prévalence, analyse spatiale, Ontario
Footnotes
Acknowledgements: Funding for this study was provided by the Government of Ontario and AllerGen NCE Inc. Population-based data were provided by the Institute for Clinical Evaluative Sciences (ICES). The sponsors/funders had no influence on design and conduct of the study; collection, management, analysis and interpretation of the data; or preparation, review and approval of the manuscript. The opinions, results and conclusions are those of the authors and no endorsement by the Government of Ontario, AllerGen NCE Inc. or ICES is intended or should be inferred.
Conflict of Interest: None to declare.
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