Inflammatory bowel disease (IBD), characterized by chronic gastrointestinal inflammation, represents a significant childhood chronic disease. In this thesis, a case ascertainment definition of paediatric-onset IBD was validated using administrative data and developed the Ontario Crohn’s and Colitis Cohort (OCCC). The epidemiology of paediatric IBD in Ontario was described, demonstrating that Ontario has one of the highest worldwide incidence rates. Statistically significant increases in incidence were noted in 0-4 year olds (5.0%/year, p=0.03) and 5-9 year olds (7.6%/year, p<0.0001), but not in other age groups. Lower income children were more likely to be hospitalized at least once (hazard ratio (HR) 1.17, 95% confidence intervals (CI) 1.05-1.30) or visit the ED (HR 1.21, 95% CI 1.09-1.35) and had more IBD-related physician visits (odds ratio (OR) 3.73, 95% CI 1.05-13.27). Lower income children with Crohn's disease (CD) (not ulcerative colitis [UC]) were more likely to undergo intra-abdominal surgery within 3 years of diagnosis (OR 1.22, 95% CI 1.01-1.49), especially if diagnosed after 2000 (OR 1.79, 95% CI 1.27-2.53). Finally, changes in health services utilization and surgical rates were described, as were changes in specialist care provision and immunomodulator use in children with IBD between 1994-2007. The changes to care included increased outpatient care provided by paediatric gastroenterologists, and increased immunomodulator use. Children diagnosed with CD, but not UC, in recent years had lower surgical rates. In CD patients, intra-abdominal surgical rates within three years of diagnosis decreased from 18.8% in children diagnosed in 1994-1997 to 13.6% in those diagnosed in 2001-2004 (P = 0.035). When stratified by age at diagnosis, this decrease was significant in children diagnosed ≥10 years old (OR 0.67, 95% CI 0.48-0.93). The OCCC will continue to be used to investigate the epidemiology and burden of paediatric IBD and to improve the care received by children with IBD in Ontario.

Multiple transitions between care settings have been reported to affect the quality of life of the older adults and their families. In Canada, there have been no studies that have examined transitions between care settings at the end of life in older adults who are on homecare. The aim of this thesis was to address this gap, and to describe transitions between care settings in older homecare clients towards the end of their life and examine what personal, health system and health service use factors predict these transitions. The sample used in this study was the cohort of individuals 65 years and older(n=7866) who died in Manitoba within the fiscal years 2003-2006, and who received homecare for at least 30 days in the last year of their life. The outcome variables in this study were transitions and independent variables included demographic (e.g., age, sex), health service use (homecare days) and system factors (e.g., hospital bed supply). The study involved secondary data analysis of anonymized administrative data (the hospital, homecare and personal care home (PCH) data), vital statistics data, health insurance registry, census data, and annual provincial statistical reports. Descriptive and inferential data analyses methods were used to analyze the data in the study. It was found in the study that more than half of the homecare clients had one or more transitions between care settings in their last month of life, and more than half of the homecare clients in the study died in hospitals. Homecare clients who were males, in the 75-84 years age group, received more homecare days and lived in regions of high hospital bed supply were more likely to have one or more transitions in the last month of their life, and those who were single, in the lower income quintile groups, lived in regions of high physician and PCH bed supply had lower odds of having one or more transitions. The findings suggest the need for increasing palliative care and homecare services to reduce transitions and hospital deaths at the end of life. Increasing physician supply, particularly in rural areas should also be considered. Future studies should also attempt to classify which of the transitions towards the end of life were essential or burdensome.

Aggressive hospital discharge policies adopted in the 1990s led to an influx of patients recovering from acute illness accessing post-acute home care services. Performance of the post-acute home care program in the Saskatoon Health Region was examined using formative program evaluation methods. Brief surveys of clients and nurse providers captured: care objectives and service outcomes; patient-centeredness; trust in providers; health improvement/decline; emotional/social functioning; functional status; injury avoidance; and overall quality. For clients, perceptions of quality were significantly affected by patient centeredness and experiencing unexpected health complications, which accounted for 83.0% of the variation. For nurse providers, overall quality of care was significantly related to patient centeredness, service outcomes, team communication and injury avoidance. Analysis revealed for clients with complex needs, the service period could be extended from 60 to 97 days which would cover 50.0% of clients. The research examining administrative data predicted the dependent variable Log of Total Care Hours (TCH) to enable analysis using General Linear Modelling. The results showed post-acute home care clients referred from Emergency Departments received approximately 84.2 % more TCH; post-acute home care clients referred from Surgical wards received approximately 42.1% more TCH; and post-acute home care clients referred from Cardiology received approximately 66.3% more TCH than clients referred from the community. Furthermore, single clients received more TCH than married clients. Nursing chart reviews of post-acute home care clients with wound care also predicted the Log of TCH to enable analysis using General Linear Modelling. Post-admission, 11.3% of post-acute home care clients receiving wound care displayed clinical signs and symptoms of emerging infection, while 19.7% displayed clinical signs and symptoms of acquired infection. Post-acute home care clients receiving wound care experiencing injury, trauma or harm while admitted to home care received approximately 53.3% TCH; and post-acute home care clients who acquired an infection after admission received approximately 70.2% TCH. The implications of this research suggest there is room to improve post-acute home care services to address client re-hospitalisation, unexpected health symptoms/complications, and wound care.

Background/Objectives: West Nile neuroinvasive disease (WNND) is a severe neurological illness that develops in approximately 1% of individuals infected with West Nile virus (WNV). Manifesting most frequently as encephalitis (WNE), meningitis (WNM), or acute flaccid paralysis (WNP), there is no cure for WNND beyond supportive care and rehabilitation, and death or permanent disability are common outcomes. As the virus arrived in North America less than 20 years ago, determinants of severe disease progression following infection are still being explored. This project is the first to examine comorbid conditions as risk factors of WNND in Ontario using a population-based study design. As prevention is the only avenue of defence against WNND, identifying comorbid risk factors of WNND would allow for public health prevention campaigns targeted to high-risk groups. The main objectives of this thesis were to explore whether pre-existing chronic diseases were associated with the development of WNND, or any of its three manifestations (i.e., encephalitis, meningitis, acute flaccid paralysis). Methods: This was a retrospective, population-based study including all Ontario residents with a confirmed diagnosis of WNV infection between January 1, 2002 and December 31, 2012. A cohort of individuals with WNV was identified from a provincial laboratory database and individually-linked to health administrative databases. In the WNV cohort, individuals with WNND and 13 comorbid conditions were identified using algorithms based on ICD-10-CA diagnostic codes. Incidence of WNND following WNV infection was then compared among individuals with and without comorbid conditions using relative risks estimated by log binomial regression. Additionally, risk ratios were calculated for associations between specific comorbid conditions and WNND neuroinvasive manifestation (i.e., encephalitis, meningitis, acute flaccid paralysis). Finally, associations between Charlson Comorbidity Index (CCI) scoring and development of WNND was examined through calculation of relative risk using log binomial regression. Results/Potential Impact: Risk factors for WNND included male sex (aRR: 1.21; 95% CI: 1.00-1.46) in addition to the combined effect of hypertension and increasing age (5-year intervals) (aRR: 1.16; 95% CI: 1.08-1.24); WNND was also associated with increasing CCI scores; individuals in low, medium, and high categories had increased risk compared to individuals with a score of zero, but the greatest risk was in the high CCI category (aRR: 3.45; 95% CI: 2.25-4.83) Male sex (aRR: 1.32; 95% CI: 1.00-1.76), increasing age (aRR: 1.02; 95% CI: 1.02-1.03), and being immunocompromised (aRR: 2.61; 95% CI: 1.23-4.53) were associated with development of WNE. No risk factors were identified for WNM and WNP. Identification of comorbid risk factors of WNND will allow public health officials to identify high-risk groups and to develop prevention strategies targeted for vulnerable individuals.

No description available.

Résumé : La douleur lombaire (DL) est l’une des conditions musculosquelettiques les plus fréquentes et coûteuses au Canada. La prévalence annuelle de DL aigüe varierait de 19 % à 57 %, et un patient sur quatre souffrirait de récurrence dans la même année. La présente étude vise donc à produire une analyse descriptive de l’épidémiologie de la DL récurrente à l’échelle de la population. Une nouvelle approche méthodologique est proposée afin d’optimiser l’identification de vrais cas incidents de DL récurrente à partir d’une analyse secondaire de données administratives. Puisque 10 % des patients ayant de la DL seraient responsables de 80 % des coûts qui y sont associés, nous avons également déterminé la tendance séculaire des coûts d’interventions médicales des patients récurrents incidents entre 2003 et 2008. En utilisant le fichier des services médicaux rémunérés à l’acte de la Régie de l’assurance maladie du Québec, des cohortes prévalentes ont été construites à partir de 401 264 dossiers de patients ayant consulté au moins trois fois pour de la DL entre 1999 et 2008. Onze ans d’historique médical des 81 329 patients de la cohorte de 2007 ont ensuite été analysés afin d’exclure les patients ayant eu des consultations antérieures de DL. Une valeur prédictive positive et un coefficient de Kappa élevés ont permis d’identifier une clairance optimale pour récupérer les cas véritablement incidents. Les coûts de consultations ont ensuite été calculés pour tous les patients incidents de 2003 à 2007 à partir des manuels de facturation. Nous avons observé une prévalence annuelle de la DL récurrente de 1,64 % en 2000 chez les hommes diminuant à 1,33 % en 2007. Cette baisse a majoritairement eu lieu dans le groupe d’âge des 35-59 ans. Les femmes âgées (> 65 ans) étaient 1,4 fois plus à risque de consulter un médecin de manière récurrente que les hommes du même âge. L’incidence annuelle de la DL en 2007 était de 242 par 100 000 personnes. Les hommes de 18 à 34 ans étaient 1,2 fois plus à risque que les femmes de développer un premier épisode récurrent et les personnes âgées 1,9 fois plus à risque que les jeunes. L’incidence annuelle a diminué de 12 % entre 2003 et 2007 pendant que les coûts totaux augmentaient de 1,4 %. La médiane des coûts était la plus élevée chez les femmes âgées et tendait à augmenter dans le temps. Ces analyses secondaires suggèrent de s’intéresser particulièrement à la DL chez les personnes très âgées, et de déterminer si la baisse de fréquence de consultations récurrentes observée dans le temps est liée à une meilleure gestion de la DL ou à un problème d’accessibilité. Les coûts devraient faire l’objet d’un suivi continu pour limiter les hausses. // Abstract : Low back pain (LBP) is one of the most frequent and costly musculoskeletal health conditions in Canada. Annual prevalence was found to vary between 19 % and 57 % and likely one out of four patients experience a LBP recurrence within one year. The body of knowledge on the prevalence of recurrent LBP is still limited. This study sought to present a descriptive analysis on the epidemiology of recurrent LBP in a medical population. A new methodology is also proposed to identify true cases of incident recurrent LBP. Since 10 % of LBP patients have been reported to generate 80 % of the costs, we will sought to determine the secular trend of medical costs for the incident cohorts of 2003 to 2008. Using the Canadian province of Quebec medical administrative physicians’ claims database, 401 264 prevalent claims-based recurrent LBP patients were identified between 1999 to 2008 for having consulted at least three times for LBP in a period of 365 days. The medical history of 81 329 prevalent patients in 2007 was screened for a retrospective period of 11 years. High positive predictive values and Kappa statistics were used to determine the optimal clearance period for capturing true incidence cases among patients with no prior encounters for LBP. Physicians’ claims manuals were then used to apply a price for every intervention provided to LBP incident patients in their index year and follow-up years. We observed a decrease from 1.64 % to 1.33 % in the LBP annual prevalence between 2000 and 2007 for men. This decrease was mostly observed between 35 and 59 years of age. Older women (≥ 65 years) were 1.4 times more at risk to consult a physician for LBP in a recurrent manner than older men. The annual incidence in 2007 of adult claims-based recurrent LBP was 242 per 100 000 persons. Males of 18 to 34 years of age were found 1.2 times more at risk than their counterparts. Altogether, elderlies were 1.9 times more at risk than young adults to consult in a recurrent manner for LBP. The annual incidence decreased by 12 % between 2003 and 2007, while the direct costs increase by 1.4 %. The median cost for consultations was highest for elder women and increasing in time. These secondary analyses emphasize the importance to keep the watch on the elders in regards to LBP, and to determine if the timely decrease in morbidity is related to improvements in LBP management or to a medical accessibility issue. Also, costs will need to be surveyed on a regular basis to limit the impact of future increases.

Les adolescents qui décrochent de l’école secondaire arrivent difficilement à s’intégrer dans une économie axée sur le savoir et éprouvent plusieurs problèmes d’ajustement à l’adolescence et à l’âge adulte. Pour prévenir le décrochage scolaire, une étape cruciale consiste à dépister efficacement les élèves les plus à risque. Deux formes de dépistage axées sur des données peuvent être utilisées en milieu scolaire: une forme utilisant des informations auto-rapportées par les élèves à partir de questionnaires, et une autre fondée sur des informations administratives consignées au dossier des élèves. Toutefois, à notre connaissance, l’efficacité de ces différentes modalités n’a jamais été comparée directement. De plus, il est possible que l’efficacité relative de ces outils de dépistage soit différente selon le sexe de l’élève. Cette étude vise à comparer différents outils de dépistage pour prédire le décrochage scolaire, en tenant compte de l’effet modérateur du sexe. Les outils utilisés seront a) un questionnaire auto-rapporté validé (Archambault et Janosz, 2009) et b) un outil conçu à l’aide de données administratives, créé par une commission scolaire du Québec. La comparaison de ces outils est effectuée en termes de qualités psychométriques et d’aspect pratique pour le milieu scolaire. Pour ce faire, un échantillon de 1557 élèves (50% de garçons), âgé entre 14 et 18 ans est utilisé. Les résultats indiquent que l’indice administratif possède une capacité discriminante adéquate, mais inférieure à celle de l’indice auto-rapportée, jugée excellente. L’effet modérateur du sexe n’a pas été confirmé. Les avantages et inconvénients respectifs de ces deux modes de dépistage sont discutés. / Adolescents who drop out of high school often struggle in a knowledge-based, technologically complex society and experience many adjustment problems in adolescence and adulthood. To prevent dropout, a crucial first step consists of correctly identifying students who are most at risk. Schools can rely on two types of screening tools to identify potential dropouts: based on self–reported questionnaire or based on administrative data. However, the predictive value of risk indices based on self-reported data has never been directly compared to that of indices calculated from administrative data. Moreover, the relative efficacy of different screening tools could be different according to the student gender. The purpose of this study is to compare the efficacy, for boys and girls, of two risk indices for high school dropout: a) a validated index based on a self-reported questionnaire (Archambault & Janosz, 2009) and b) an index based on administrative data and designed by a Quebec school board. The comparison of these two screening methods is made in term of psychometric properties and practicality for school practitioners. To do so, a sample of 1557 students (50% boys), between 14 and 18 years old is used. The results show that the administrative index has an adequate discriminant capacity, but that is lower than that of the self-reported index judged excellent. These results were not moderated by gender. The comparative advantages and disadvantages of both screening methods are discussed.

L'obtention des données a été subventionnée par CIORA (Canadian Initiative for Outcomes in Rheumatology Care). CIORA a aussi financé l'analyse des données effectuées par Justine Zehr. L'Initiative Canadienne Pour Des Resultats En Soins Rhumatologiques (ICORA) a financé l'obtention des données et une partie de l'analyse statistique présentée dans ce mémoire. / La plupart des femmes ayant été atteintes d’arthrite juvénile idiopathique (AJI) continuent de souffrir d’arthrite à l’âge adulte. Certains des médicaments utilisés dans le traitement de l’arthrite tels que les corticostéroïdes et les antiinflammatoires non stéroïdiens (AINS) ne sont pas recommandés durant la grossesse. Le but de ce mémoire est d’estimer l’impact de la prise de ces médicaments sur les événements néfastes à l’accouchement chez ces femmes et leur bébé. Des données administratives sur les prescriptions de médicaments et les hospitalisations d’une cohorte de 1756 femmes ayant souffert d’AJI sont utilisées. Elles ont permis de reconstruire l’historique de consommation de médicaments contre l’arthrite chez les femmes durant la grossesse et l’année précédente. Pour ce faire, deux sous-cohortes de femmes ayant souffert d’AJI ont été formées : une pour la période grossesse et une autre pour la grossesse et l’année précédant celle-ci. Les événements d’intérêt étaient : malformations congénitales, complications néonatales, complications maternelles et petit poids pour l’âge gestationnel. Les proportions de cas présentant l’un de ces événements variaient entre 11,52% et 37,08%. Les médicaments ont été modélisés en terme d’utilisation ou de durée totale de consommation durant la période d’étude. Pour chaque événement, des modèles logistiques ont été estimés pour mesurer l’association entre la prise de médicaments et l’événement, en ajustant pour des variables de confusion potentielles : hypertension avant la grossesse, âge à l’accouchement et obtention du diplôme de secondaire. La consommation de corticostéroïdes semble augmenter statistiquement significativement le risque de présenter des malformations congénitales mais n’avoir aucun impact sur les autres événements. Aucun lien statistiquement significatif n’a été observé entre la consommation de AINS et les événements d’intérêt. / Most women diagnosed with juvenile idiopathic arthritis (JIA) continue to suffer from arthritis in adulthood. Some of the drugs used to treat arthritis such as corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) are not recommended during pregnancy. The objective of this thesis is to estimate the impact of these drugs on adverse birth outcomes in women previously diagnosed with JIA and their baby. Administrative data on drug prescriptions and hospitalizations in a cohort of 1756 women with a history of JIA were used to determine individual histories of drug use for the treatment of arthritis during pregnancy and during the year leading to the pregnancy. Two sub-cohorts of women who suffered from JIA were created : one corresponding to the pregnancy and the other to the pregnancy and the year leading to the pregnancy. The events of interest were : congenital anomalies, neonatal adverse outcomes, maternal adverse outcomes and small for gestational age babies. Proportions of the events ranged between 11,52% and 37,08%. Drugs were modelled in terms of use or duration of use during each of the study periods. Logistic regression models were fitted to measure the association between drugs and each of the events, adjusting for the following potential confounding variables : hypertension before pregnancy, maternal age and graduating from high school. The consumption of corticosteroids was associated with a statistically significant increased risk of congenital anomalies but had no impact on the other adverse events. No statistically significant associations were observed between consumption of NSAIDs and the adverse events of interest.

Le diabète de type 2 (DT2) est une maladie chronique associée à de graves et coûteuses complications. Dans un contexte de restriction budgétaire, il est nécessaire de pouvoir estimer les ressources à affecter à la prise en charge des maladies chroniques et donc de suivre l’évolution épidémiologique et économique d’une telle maladie. Une base de données a été construite à partir des données médico-administratives de l’assurance maladie luxembourgeoise. Elle comprenait les consommations de soins, associées au diabète et ses complications, des patients diabétiques de type 2 traités entre 2000 et 2006. L’objectif était d’étudier les champs d’utilisation de ces données et leurs applications possibles pour les décisions en santé publique. Cette thèse en donne quelques exemples. En 2006, la prévalence du DT2 au Luxembourg était de 3,79% (N= 17 070). Un algorithme a permis d’identifier trois stades de la néphropathie diabétique (3,77% des cas de DT2 en 2006). L’analyse de l’adhérence aux recommandations européennes de bonnes pratiques médicales a mis en évidence une situation critique associée à certains facteurs (médecin traitant, type de traitement, région de résidence…). Les dépenses moyennes d’un patient en hémodialyse a été estimé à 116 647€/patient en 2006. Enfin, une analyse médico-économique a montré la dominance coût-efficace d’une stratégie d’implémentation de la dialyse péritonéale sur la situation actuelle. Malgré les difficultés à évaluer leur qualité, les données médico-administratives offrent une source d’informations précieuses pour les décideurs publics et les professionnels de la santé, dans le but d’améliorer la prise en charge des patients. / Type 2 diabetes (T2D) is a chronic disease associated with many severe and costly complications. In a context of budgetary constraint, it is necessary to obtain an estimate the amount of resources to allocate to the management of chronic diseases. This includes monitoring the epidemiologic and economic evolutions. A database was built from medico-administrative databases of the national health insurance of Luxembourg. It included the healthcare consumptions associated with diabetes and its complications, of all type 2 diabetic patients treated in Luxembourg between 2000 and 2006. The objectives were to study the fields of use of this database and the possible applications for public health decision-making. This thesis gives some examples. In 2006, T2D prevalence in Luxembourg was 3.79% (N= 17070). An algorithm was built and permitted to identify three stages of diabetic nephropathy (3.77% of T2D cases in 2006). The analysis of the adherence to European follow-up guidelines showed a critical situation associated to several factors (treating physician, type of treatment, living region…). The mean costs associated with patients in dialysis were estimated at 116 647€/patient in 2006. Finally, a health-economic evaluation showed the dominance of a strategy promoting peritoneal dialysis in Luxembourg over the present situation.

In questo studio, attraverso la realizzazione di un’indagine longitudinale basata su dati amministrativi, sono stati ricostruiti i redditi delle famiglie residenti nel comune di Brescia per gli anni 2005-2008, in una prospettiva trasversale e longitudinale, individuando situazioni di disuguaglianza, di disagio e povertà economica di alcune fasce della popolazione. L’indagine longitudinale è stata realizzata mediante il record-linkage tra i dati amministrativi provenienti dall’Anagrafe comunale e quelli fiscali del Sistema Interscambio Anagrafe Tributaria Enti Locali dell’Agenzia delle Entrate (SIATEL) per il comune di Brescia. La peculiarità e l’importanza di questo lavoro risiedono sia nell’utilizzare dati di fonte amministrativa fiscale e anagrafica nella stima sui redditi e povertà delle famiglie, sia nella possibilità di ottenere stime a livello comunale o small-area, ampliando il campo della ricerca sociale sul tema oggetto di studio. L’approccio teorico di riferimento adottato è quello unidimensionale, basato sul reddito, e relativo, in cui la povertà è definita in relazione allo standard di benessere raggiunto dalla popolazione di riferimento nel suo complesso. Pertanto, anziché la soglia di povertà nazionale, che tende a sottostimare la povertà nel nord d’Italia, è stata adottata una soglia di povertà locale, pari al 60% del reddito mediano equivalente delle famiglie residenti. / In this study the incomes of the families residing in the town of Brescia for the years 2005-2008 have been simulated in a cross-section and longitudinal perspective, through the creation of a Panel based on administrative data. The research aimed at identifying situations of inequality, dislocation and economic poverty of certain population groups. The Panel was carried out on the basis of the record-linkage administrative data from Registry Office and ” Informatics’ System of Local Italian Revenue Agency” (SIATEL), for the town of Brescia. The uniqueness and importance of this work is the use of live data in estimating income and family poverty using fiscal and personal data from registry office sources, as well as in the availability of estimates at the municipal level or small-area, thus expanding the social research on the subject of study. The theoretical approach adopted by reference is one-dimensional (based on income) and relative, in which poverty is defined in relation to the standards being achieved by the reference population as a whole. Therefore, instead of the national poverty line, which tends to underestimate poverty in northern Italy, a local poverty threshold was adopted, equal to 60% of equivalised median income of the families residing in the town of Brescia.