Abstract
Background
Canada has a single-payer, publicly-funded health care system that provides comprehensive health care, and therefore significant disparities in health outcomes are not expected in our population. The objective of this study was to determine if differences exist in endometrial cancer outcomes across regions in Ontario.
Methods
This was a population-based study of all endometrial (uterine) cancer cases diagnosed from 1996 to 2000 in Ontario and linked to various administrative databases. Univariate analyses examined trends in demographics (age, income, co-morbidities), treatment (surgical staging and adjuvant pelvic radiotherapy), and pathology (grade, histology, stage) across 14 geographic regions defined by local health integration networks (LHINs) in Ontario. Primary outcome was 5-year overall survival among LHINs, which were compared in a multilevel Cox regression model to account for clustering of patient data at the hospital level.
Results
There were 3,875 evaluable cases with complete information on demographics, treatment, pathology, and outcomes. There was significant variation in patient demographics, treatment, and pathology across the 14 LHINs. Low income level and surgery at a low-volume, community hospital without gynecologic oncologists were not associated with a higher risk of death. There was a trend towards clustering of patients within hospitals. After adjustment for covariates, there was no significant difference in survival across LHINs.
Conclusions
In the context of a single-payer, publicly-funded health care system, we did not find significant regional differences in endometrial cancer outcomes.
Key words: Endometrial neoplasms, local health integration networks (LHINs), delivery of health care, outcome assessment
Résumé
Contexte
Puisque le Canada est doté d’un régime public de soins de santé à payeur unique qui offre toute la gamme des soins, on ne s’attend pas à observer de disparités importantes dans les résultats cliniques de la population. Notre étude visait à déterminer l’existence d’écarts régionaux dans les résultats des cancers de l’endomètre en Ontario.
Méthode
Il s’agissait d’une étude représentative de tous les cas de cancer de l’endomètre (utérus) diagnostiqués entre 1996 et 2000 en Ontario et liés à diverses bases de données administratives. Des analyses univariées ont permis de dégager des tendances concernant le profil démographique (âge, revenu, comorbidités), le traitement (stadification par chirurgie et radiothérapie pelvienne adjuvante) et la pathologie (degré, histologie, stade) dans les 14 régions géographiques définies par les réseaux locaux d’intégration des services de santé (RLISS) de l’Ontario. Le principal résultat était la survie globale de 5 ans dans les divers RLISS, que nous avons comparés à l’aide d’un modèle de régression de Cox multiniveau pour tenir compte de la concentration des données des patientes dans les hôpitaux.
Résultats
Nous avons trouvé 3 875 cas évaluables pour lesquels il existait des données complètes (sur le profil démographique, le traitement, la pathologie et les résultats). Le profil démographique des patientes, le traitement et la pathologie variaient de façon significative dans les 14 RLISS. Les faibles niveaux de revenu et les chirurgies dans les petits hôpitaux communautaires sans gynécologue oncologue n’étaient toutefois pas associés à un risque de décès plus élevé. Nous avons observé une tendance à la concentration des cas à l’intérieur des hôpitaux. Compte tenu des covariables, il n’y avait pas d’écart significatif dans les taux de survie d’un RLISS à l’autre.
Conclusion
Dans le contexte d’un régime public de soins de santé à payeur unique, nous n’avons constaté aucune différence régionale significative dans les résultats des cas de cancer de l’endomètre.
Mots clés: tumeurs de l’endomètre, réseaux locaux d’intégration des services de santé (RLISS), prestation des soins de santé, évaluation des résultats
Footnotes
Acknowledgement: This work was supported by a junior scientist award in gynecologic cancer research from Cancer Care Ontario, the Mitchell Family, and the National Ovarian Cancer Association (to Dr. Kwon).
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