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Given the importance in prevention of lower extremity amputations (LEA) associated with diabetes or peripheral artery disease (PAD), we sought to document the trends of primary LEA in Quebec, Canada, from years 2006 to 2019.Using the Quebec Integrated Chronic Disease Surveillance System, we calculated crude and age-standardized annual incidence rates of primary LEA associated with diabetes and/or PAD among adults ≥40 years (99% confidence intervals [CI]), and all-cause 1-year mortality proportion trends following a primary LEA (95% CI), stratified by minor or major as the highest level of LEA during the same hospital stay and age groups. Trends were asssessed using multivariate regression models.In 2019, the crude rate of primary LEA was 116.0 per 100,000 (n=825) with 93.7 and 21.9 per 100,000 of minor (n=665) and major (n=160) LEA, respectively. A tendency of decrease by 8% (-15.0 to 0.4%) of age-standardized incidence of primary LEA was observed between 2006 and 2019, while minor LEA increased by 14.2% (3.7 to 25.9%) and major LEA decreased by 49.5% (-57.1 to -40.5%). Incidence trends remained stable among the 40-64 years, and declined by 14.6% and 20.1% for the 65-79 and ≥80 years, respectively. Major LEA decreased in all age groups, while minor LEA increased by 26.2% among the 40-64 years only. Age-standardized 1-year mortality decreased by 35.1% (95% CI: -43.4 to -25.7%) between 2006 and 2019, with a crude 1-year mortality of 11.3% in 2019.The reduction of major LEA and 1-year mortality are encouraging while increased minor LEA, especially in younger age groups, emphasizes the importance to further improve preventive care.

Background Vascular diseases, encompassing coronary heart disease (CHD), cerebrovascular disease (CVD), and peripheral artery disease (PAD), are leading causes of the global mortality and morbidity burdens. Our objective was to evaluate the temporal trends in the burden of vascular diseases in the province of Quebec from 2000 to 2015. Methods We identified subjects aged ≥ 20 years with vascular diseases in the Quebec Integrated Chronic Disease Surveillance System (a combination of 5 provincial health administrative datasets). We identified Quebecers with CHD, CVD, or PAD by tracking codes identifying vascular diseases (and interventions for CHD) in the hospitalization datasets. We used the 2011 Quebec standard population for age standardization. Results In 2015, the crude prevalence of vascular diseases was 7.3% (n = 473,305), and the all-cause crude mortality rate was 6.6% (n = 31,320). Age-standardized prevalence of vascular diseases increased relatively by 21.4% between 2000 (5.6%; 99% confidence interval [CI], 5.5-5.6) and 2015 (6.8%; 99% CI, 6.7-6.8), whereas the age-standardized incidence and mortality rates showed relative decreases of 46.2% and 32.6%, respectively. PAD and CVD had lower prevalence and incidence but higher mortality than CHD. Most patients with CHD only had this vascular disease in contrast to patients with PAD who generally had diseases involving more than 1 vascular bed. CHD only and CHD with PAD ranked first and second, respectively, in mortality burdens. Conclusions During the last decade, the age-standardized incidence and mortality rate of vascular diseases declined, but their prevalence increased with the overall burden of vascular diseases remaining substantial in Quebec, Canada.

Background It is unclear whether generics are as safe as brand-name drugs in cardiology. For public health surveillance purposes, we evaluated if switching from the brand-name losartan, valsartan, or candesartan impacted the occurrence of the following outcomes: emergency room (ER) consultations, hospitalizations, or death. Study Design This was a retrospective cohort study. Methods This study was conducted in the Quebec Integrated Chronic Disease Surveillance System, including healthcare administrative data of the population of Quebec, Canada. We included brand-name users of losartan, valsartan, or candesartan aged ≥ 66 years who had undergone ≥ 30 days of stable treatment on the brand-name drug prior to cohort entry (substitution time-distribution matching was used to prevent immortal time bias). Outcomes up to 1 year were compared between groups using multivariable Cox proportional hazards regression models (validity assumptions were verified). Results In our cohorts (losartan, n =15,783; valsartan, n =16,907; candesartan, n =26,178), mean age was 76–78 years, 59–66% were female, 90–92% had hypertension, and 13–15% had heart failure. Validity assumptions were violated for losartan only. For patients switched to generic valsartan, the hazard ratio (95% confidence interval) was 1.07 (0.99–1.14) for ER consultation, 1.26 (1.14–1.39) for hospitalization, and 1.01 (0.61–1.67) for death. The corresponding rates for candesartan were 1.00 (0.95–1.05), 0.96 (0.89–1.03), and 0.57 (0.37–0.88), respectively. Conclusions We observed an increased risk of hospitalizations for patients switched to generic valsartan, and a decreased risk of death for patients switched to generic candesartan, compared with those who continued taking the brand-name drug. The differences between generic and brand-name drugs may lead to some differences in public health outcomes, but this safety signal must be further studied using other cohorts and settings. Electronic supplementary material The online version of this article (10.1007/s40268-020-00307-2) contains supplementary material, which is available to authorized users.

Insulin pumps improve glycemic control and quality of life in children with type 1 diabetes (T1D). Canada's provinces have implemented universal pediatric programs to improve access. However, these programs provide differing financial coverage, allowing for unique cross-jurisdictional comparisons.To evaluate possible socioeconomic status (SES) disparities in pump uptake in Québec, where pumps are fully funded, with those in Manitoba, where pumps are partially funded.Using health administrative databases and a clinical registry, parallel, population-based cohort studies of children with diabetes were conducted from April 1, 2011, in Québec, and April 1, 2012, in Manitoba, until March 31, 2017. In analysis conducted from July 1, 2019, to November 30, 2021, multivariable Cox proportional hazards regression models were applied to study the association between pump uptake and SES, defined using validated area-based material and social deprivation indices. Children aged 1 to 17 years with T1D were identified using a validated definition in administrative data (Québec) and a clinical registry (Manitoba). Those using pumps before the initiation of provincial programs were excluded.Socioeconomic status.Insulin pump uptake.A total of 2919 children with T1D were identified in Québec: 1550 male (53.1%), mean (SD) age at diagnosis, 8.3 (4.4) years, and 1067 (36.6%) were using a pump. In Manitoba, 636 children were identified: 364 male (57.2%), mean (SD) age at diagnosis, 8.8 (4.4) years, and 106 (16.7%) were using a pump. In Québec, the mean age at diagnosis of T1D was lower in children using the pump compared with those not using a pump (7.6 [4.1] vs 8.7 [4.5] years); sex distribution was similar (562 [52.7%] vs 988 [53.3%] male). No differences in mean (SD) age at diagnosis (8.8 [4.4] vs 8.8 [4.3] years) or sex (57 [53.8%] vs 307 [57.9%] male) were noted in both groups in Manitoba. Increasing material deprivation was associated with decreased pump uptake in both Québec (adjusted hazard ratio [aHR] 0.89; 95% CI, 0.85-0.93) and Manitoba (aHR, 0.70; 95% CI, 0.60-0.82). Inclusion of ethnic concentration did not change this association. Socioeconomic disparities in pump uptake were greater in Manitoba than Québec (P = .006 by t test; Cochran Q, 8.15; P = .004; I2 = 87.7%; 95% CI, 52.5%-96.8%).The results of this study suggest that the program of full coverage for pumps available in Québec partially mitigates observed SES disparities in uptake and may be a model to improve access for all children with T1D.

Introduction: Non-traumatic lower limb amputations (LLA) represent an important complication of diabetes (DM) and peripheral arterial disease (PAD). In Quebec, Canada, the latest data between 1996 to 2004 suggested a reduction in the incidence of LLA while other Canadian provinces observed a recent increase between 2010 and 2016. Our objective was to update the incidence trends of LLA in Quebec from fiscal years 2006 to 2019. Methods: Age-standardized incidence of LLA among individuals ≥40 years was assessed using the Quebec Integrated Chronic Disease Surveillance System (n=4,527,533 in 2019). The mean age of incident cases and the presence / duration of DM and/or PAD was collected. Estimations were presented for all, by sexes and by types of LLA (minor: below the knee; major: knee and above), with 99% confidence intervals (CI). Results: Between 2006 and 2019, incident cases of LLA increased from 818 to 1,099 but age-standardized incidence remained stable (Figure 1) for both sexes. Men had a higher age-standardized incidence of LLA then women (32.7 per 100,000 [99% CI: 29.7-35.9] vs 12.9 per 100,000 [11.2-14.9] in 2019). From 2006 to 2019, the age-standardized incidence of major LLA showed a relative decrease of 48% while minor LLA remained stable (Figure 1). Reduction in age-standardized incidence of major LLA was attributable to men (3.8 per 100,000 [2.7-5.3] to 1.7 per 100,000 [1.1-2.6]). The mean age of incident cases went from 68.2 to 69.5 years from 2006 to 2019 (72.4 for women and 68.3 for men in 2019). Ninety-eight percent of LLA had DM, while 95% had PAD and 95% had both in 2019. Between 2006 and 2019, the average time between the first LLA and DM diagnosis increased from 7.0 to 14.7 years and from 2.0 to 2.6 years for PAD. Conclusions: Although the age-standardized incidence of LLA is stable, men remain at higher risk then women. The portrait of incident cases is changing towards an older average age, longer DM duration and a reduction of major LLA. These results emphasize the importance to improve further preventive care of LLA in Quebec.

Introduction: The progression of type 2 diabetes (T2D) is unique to each patient and can be depicted through individual temporal trajectories. Latent group trajectory methods (latent growth mixture models [LGMM] or latent class growth analysis [LCGA]) can be used to classify similar individual trajectories in a priori non-observed groups (latent groups), sharing common characteristics. Although increasingly used in the field of T2D epidemiology, many questions remain regarding the utilization of these methods. Objective: To review the literature of longitudinal studies using latent group trajectory methods among individuals with T2D. Methods: MEDLINE (Ovid), EMBASE, CINAHL and Web of Science were searched through August 25 th , 2021. Data were collected on the type of method used (LGMM or LGCA), characteristics of studies and quality of reporting using the GRoLTS-Checklist. Results: From the 4,694 citations screened, a total of 38 studies were included. The studies were published between 2010 and 2021. Total follow-ups ranged from 8 weeks to 11 years, with 95% (36 out of 38) studies with a follow-up of 1 year of more. The characteristics of studies are presented in Table 1. Regarding the quality of reporting, trajectory groups were adequately presented, however many studies failed to report important decisions made for the trajectory group identification. Many studies considered trajectory groups as exposures to a subsequent outcome. Yet, issues in relation with selection bias, immortal bias and residual confounding were suspected and poorly addressed. Conclusions: Although LCGA were preferred, the context of utilization, data sources and research questions were diverse and unrelated to the type of method used. We recommend authors to clearly report the decisions made in trajectory groups identification.

Background: Inequities between guideline-recommended drugs (GRD) exposure and socioeconomic status might exist. The objective was to assess the association between a material and a social deprivation index and GRD exposure following a first acute myocardial infarction (AMI) in older adults in the province of Quebec. Methods: We conducted a retrospective cohort study using the Quebec Integrated Chronic Disease Surveillance System. Elderly ≥66 years, hospitalized for a first AMI between January 1, 2006, and December 31, 2011 and covered by the public drug plan were identified. Exposure to GRD (i.e. simultaneous use of 1) antiplatelet, 2) beta-blocker, 3) lipid-lowering and 4) angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker drugs) was assessed 30 and 365 days following hospital discharge. Associations between deprivation index and GRD exposure were estimated with log-binomial regressions adjusting for potential confounders. Results: Exposure to GRD was 52.2% and 48.0%, 30 and 365 days after hospital discharge, respectively. No statistically significant association was observed in multivariate analysis for both time points. Thirty days post hospital discharge, adjusted prevalence ratio of non-exposure to GRD was 0.98 (95% confidence interval [CI]: 0.95-1.02) for most materially deprived vs. least deprived and 1.04 (95% CI: 0.99-1.08) for most socially deprived vs. least deprived. Similar results were observed for 365 days. Conclusion: Exposure to GRD after a first urgent AMI among older adults insured by the public drug plan in the province of Quebec is relatively low. Reasons and risk groups for this low exposure should be studied to improve secondary prevention. However, results suggest equitable access to GRD, regardless of deprivation.

ObjectivesTo evaluate the evolution of the burden of aortic stenosis (AS) by sex in the province of Quebec from 2006–2007 to 2018–2019 and compare the percentage of mortality between people who underwent aortic valve intervention and those who did not.MethodsPersons aged ≥20 years were identified from the Quebec Integrated Chronic Disease Surveillance System using International Classification of Diseases and intervention codes in the hospital files.ResultsIn 2018, the crude prevalence and incidence of AS were 0.89% (99% CI 0.89 to 0.90) (n=59 025) and 1.39 per 1000 (1.35 to 1.43) (n=9105), respectively. Age-standardised prevalence and incidence of AS diagnosis increased between 2006 and 2018 from 0.67% (0.66 to 0.68) to 0.75% (0.74 to 0.76) and from 0.91 per 1000 (0.88 to 0.95) to 1.20 per 1000 (1.17 to 1.23), respectively. Among incident AS, the age-standardised percentage of valve interventions increased from 11.7% (10.9 to 12.6) to 14.5% (13.9 to 15.3). This increase was only observed in men. The 30-day mortality was stable among patients with incident AS treated conservatively, from 6.9% (6.5 to 7.4) to 7.3% (6.9 to 7.6), and decreased from 7.6% (6.1 to 9.3) to 3.8% (3.1 to 4.7) among operated patients with incident AS. This decrease was only observed in women. However, from 2010, the age-adjusted mortality among prevalent AS tended to be higher in women.ConclusionsIn the province of Quebec, age-standardised prevalence and incidence of AS diagnosis increased between 2006 and 2018. Among incident AS, there was an increase in valve intervention in men and a decrease in 30-day mortality in women who underwent valve intervention. Overall and age-standardised mortality remained higher in women.

Introduction: In the last decade, an increase in the prevalence and a reduction in the incidence of diabetes have been observed in many countries including Canada. Yet, some Canadian provinces depicted an elevation in incidence rates among younger age groups. Our objective was to document these trends in the province of Quebec from fiscal years 2001 to 2017. Hypothesis: Prevalence is increasing because of raising incidence in individuals aged Methods: Prevalence, incidence and all-cause mortality among cases of diabetes ≥20 years were assessed using the Quebec Integrated Chronic Disease Surveillance System (n=6,551,045 in 2017). Estimations were age-standardized or stratified by 10-year age groups. Results: In 2017, the crude prevalence and incidence of diabetes were 9.9% [99% confidence interval: 9.9-10.0] (n=651,370) and 6.0 per 1,000 inhabitants [5.9-6.0] (n=35,355), respectively. Between 2001 and 2017, the age-standardized prevalence increased by 43% (6.3% [6.3-6.3] to 9.0% [9.0-9.1]), while age-standardized incidence decreased by 29% (8.3 per 1,000 [8.2-8.4] to 5.9 per 1,000 [5.9-6.0]). In every age group, the prevalence increased steadily with progressive stabilization from 2011 and onward, except for the 60-69 years old group who depicted a reduction from 2012 to 2017. Incidence remained stable among Conclusions: The rise and stabilization of diabetes prevalence could be due to a reduction in incidence in patients aged ≥50 years and mortality among all age groups. Prevention of diabetes should be a priority among individuals aged

Background Cardiovascular effects of environmental noise are a growing concern. However, the evidence remains largely limited to the association between road traffic noise and hypertension and coronary heart diseases. Objectives To investigate the association between long-term residential exposure to environmental/transportation noise and the incidence of myocardial infarction (MI) in the adult population living in Montreal. Methods An open cohort of adults aged 45 years old and over, living on the island of Montreal and free of MI before entering the cohort was created for the years 2000–2014 with the Quebec Integrated Chronic Disease Surveillance System; a systematic surveillance system from the Canadian province of Quebec starting in 1996. Residential noise exposure was calculated in three ways: 1) total ambient noise levels estimated by Land use regression (LUR) models; 2) road traffic noise estimated by a noise propagation model CadnaA and 3) distances to transportation sources (roads, airport, railways). Incident MI was based on diagnostic codes in hospital admission records. Cox models with time-varying exposures (age as the time axis) were used to estimate the associations with various adjustments (material deprivation indicator, calendar year, nitrogen dioxide, stratification for sex). Indirect adjustment based on ancillary data for smoking was performed. Results 1,065,414 individuals were followed (total of 9,000,443 person-years) and 40,718 (3.8%) developed MI. We found positive associations between total environmental noise, estimated by LUR models and the incidence of MI. Total noise LUR levels ranged from ~44 to ~79 dBA and varied slightly with the metric used. The adjusted hazard ratios (HRs) (also adjusted for smoking) were 1.12 (95% Confidence Intervals [CI]: 1.08–1.15), 1.11 (95%CI: 1.07–1.14) and 1.10 (95%CI: 1.06–1.14) per 10 dBA noise levels increase respectively in Level Accoustic equivalent 24 h (LAeq24 h), Level day-evening-night (Lden) and night level (Lnight). We found a borderline negative association between road noise levels estimated with CadnaA and MI (HR: 0.99 per 10 dBA; 95%CI: 0.98–1.00). Distances to major roads and highways were not associated with MI while the proximity to railways was positively associated with MI (HR for ≤100 vs > 1000 m: 1.07; 95%CI: 1.01–1.14). A negative association was found with the proximity to the airport noise exposure forecast (NEF25); HR ( 1000 m) = 0.88 (95%CI: 0.81–0.96). Conclusions These associations suggest that exposure to total environmental noise at current urban levels may be related to the incidence of MI. Additional studies with more accurate road noise estimates are needed to explain the counterintuitive associations with road noise and specific transportation sources.

Green spaces (GS) have many functions that can moderate the climate change impact and help prevent disease and thus alleviate public health expenses in a context of aging societies. However, several socioeconomic, demographic and geographic processes may render the access to GS challenging. Moreover, it is often critical to know what type of GS service to develop at a specific place. Also, measurements accuracy issues could be critical for planning and decision making. As an example of what could happen in many other cities of different sizes, we modeled and compared the access to GS, including several of their specific functions, in the Census Metropolitan Areas (CMA) of Montreal and Quebec City in Canada. We used the Quebec Integrated Chronic Disease Surveillance System (QICDSS) (average of 3 million people per year over 1996–2011) to measure over time, the proximity of each individual to the closest GS boundary using travel costs and spatial interaction models. ANOVA models and their corresponding base regressions were used to evaluate the statistical significance of the relationship of GS distances and surface to density, deprivation, gender and age, including interaction terms. The spatial clustering of the reduction of distances to GS was evaluated on a chronological basis. Unlike the larger CMA of Montreal, Quebec City CMA showed greater equity in access to GS, largely due to the specific geographic insertion of linear GS. The CMA of Montreal showed an improvement in the access to GS which benefits the wealthy in the densest areas on the island of Montreal. Everything happens as if a green gentrification process affects the access to GS in Montreal. Our results suggest that for the promotion of GS as an important element of primary prevention in public health, both the quality or functions of GS and the geographic determinants of their access are of higher importance than a simple consideration of total GS surface per capita as often used by decision makers or public health promoters. They also underline the limits of standard measurements of attraction and accessibility and the complexity for large cities to promote environmental justice, given the complexity of their socio-demographic processes.

Objective This study proposes the DEDE (Door-from-Emergency to Door-to-EVAR [endovascular aneurysm repair]) time as a new metric for ruptured abdominal aortic aneurysm (RAAA) delay time to surgery, permitting coherent centralization in large territories. It demonstrates how the DEDE time can be applied, using data from the province of Quebec, and looks at its potential effect on 30-day mortality. Methods We used the Quebec Integrated Chronic Disease Surveillance System (QICDSS), the linkage of five health administrative databases, to build a retrospective cohort of RAAA patients repaired operatively between April 1, 2006, and March 31, 2013. A validated algorithm was used to identify open surgical repair (OSR) and EVAR patients. Hospitals performing these operations were further characterized according to their location, volume of RAAA, types of surgeries (OSR vs EVAR), and surgeon's volume. Logistic and log-binomial regression analyses identified the risk of 30-day mortality with age, sex, hospital volume, and surgical groups as variables. Using the DEDE 90 metric and the attributable fraction, we projected how centralization and increasing the number of EVAR would affect the 30-day mortality. Results Among patients aged ≥65 years, 895 RAAAs were identified. OSR was performed in 839 patients (93.7%) and EVAR in 56 (6.3%). The overall 30-day mortality was 34.4%, and more specifically, was 35.5% for OSR compared with 17.9% for EVAR ( P = .0046). RAAAs were treated in 39 hospitals, including 16 centers averaging less than one RAAA repair per year. Low-volume (39.4%) vs high-volume centers (32.5%) had similar 30-day mortality ( P = .2198). In the multivariate analysis, the relative risk for OSR was 1.95 ( P = .0211) and was not significant for hospital volume. Applying the DEDE 90 metric and increasing access to EVAR to 50% of patients, the overall 30-day mortality would be 26.8%. Conclusions DEDE 90 is a new metric for a coherent centralization model, particularly in large territories, where transport time is crucial. Increasing access to EVAR performed in high-volume centers, with consideration to transport time, could improve the 30-day mortality after a RAAA repair.

Background: Even with many direct oral anticoagulant options, brand-name or generic warfarin is still widely used to prevent atherothrombotic events in cardiology. Federal standards regulate bioequivalence of generic vs. brand-name drugs through comparative bioavailability studies but does not regulate clinical equivalence nor tolerability in a “real-life” settings. Through public health surveillance, we have evaluated the impact of the generic warfarin commercialization on health care utilization: emergency room (ER) consultations or hospitalizations. Methods: We used an interrupted time series analysis using the Quebec Integrated Chronic Disease Surveillance System, a surveillance system from the second populous province in Canada (~8.3 million in 2017). Rates of health care utilization for warfarin users (n=280,158) aged ≥ 66 years were calculated for 6-month periods, 5 years before up to 15 years after warfarin commercialization (from January 1996 to January 2016). Periods before and after generic warfarin commercialization were compared by negative binomial segmented regression models for all users with a specific variable for generic or brand-name users. Sensitivity analyses were also conducted. Results: Generic warfarin analogs (n=5) were commercialized from January 2001. There was an approximated mean rate of 1134 ER or hospitalizations for 1000 brand-name and generic users per 6-month period, similar before and after generics commercialization. After generics commercialization, there was an immediate increase in rates of health care utilization for generic (9.9%) vs. brand-name users (0%), a statistically significant difference (9.9% [95% confidence interval: 4.4% to 15.5%], p = 0.0001). Rates of health care utilization remained stable and higher for generic vs. brand-name users throughout the period after generics commercialization. Conclusion: Among generic warfarin users, we observed an increased rates of health care utilization soon after generics commercialization. Risk and survival analysis studies controlling for potential confounders are required to deepen this pharmacovigilance signal as stricter licensing process may be required.

Background— Once the patent of a brand-name drug expires, generic drugs are commercialized, and substitution from brand-name to generics may occur. Generic drug equivalence is evaluated through comparative bioavailability studies. Few studies have assessed outcomes after generic drug commercialization at a population level. We evaluated the impact of 3 generic angiotensin II receptor blockers commercialization on adverse events: hospitalizations or emergency room consultations. Methods and Results— This is an interrupted time series analysis using the Quebec Integrated Chronic Disease Surveillance System. Rates of adverse events for losartan, valsartan, and candesartan users (N=136 177) aged ≥66 years were calculated monthly, 24 months before and 12 months after generics commercialization. Periods before and after generics commercialization were compared by negative binomial segmented regression models. Sensitivity analyses were also conducted. For all users, there was a monthly mean rate of 100 adverse events for 1000 angiotensin II receptor blocker users before and after generic commercialization. Among generic users of losartan, valsartan, and candesartan, there was an increase in rates of adverse events of 8.0% (difference of proportions versus brand-name, 7.5% [95% confidence interval, −0.9% to 15.9%]; P =0.0643), 11.7% (difference of proportions, 17.1% [95% confidence interval, 9.9%–24.3%]; P P P =0.0033) ≤1 year after generics commercialization. Similar results were found in sensitivity analyses. Conclusions— Among generic users, immediate or delayed differences in adverse events rates were observed right after generic commercialization for 3 antihypertensive drugs. Rates of adverse events remained higher for generic users. Increases were more pronounced for generic candesartan, which is the studied product with the largest difference in comparative bioavailability. Risk and survival analysis studies controlling for several potential confounding factors are required to better characterize generic substitution.

Introduction Avec l'accroissement du fardeau des maladies chroniques, la surveillance est fondamentale pour améliorer la prévention et la prise en charge de ces dernières. L'Institut national de santé publique du Québec a donc développé un système novateur de surveillance des maladies chroniques, le Système intégré de surveillance des maladies chroniques du Québec (SISMACQ), dont les principales caractéristiques, les forces et les limites sont présentées ici. Méthodologie Le SISMACQ est le résultat du jumelage de cinq fichiers médicoadministratifs. Mises à jour annuellement, ses données couvrent actuellement la période du 1er janvier 1996 au 31 mars 2012. Trois étapes en caractérisent le modèle opérationnel : 1) l'extraction et le jumelage des données médico-administratives grâce à divers critères de sélection; 2) les analyses (principalement la validation des définitions) et la production des mesures de surveillance et 3) l'interprétation, le dépôt et la diffusion de l'information. Le SISMACQ permet actuellement l'étude des maladies chroniques suivantes : diabète, maladies cardiovasculaires, maladies respiratoires, ostéoporose, maladies ostéoarticulaires, troubles mentaux et Alzheimer et maladies apparentées. Il permet également l'analyse de la multimorbidité et de la polypharmacie. Résultats Pour 2011-2012, le SISMACQ contenait des données sur 7 995 963 Québécois, et leur moyenne d'âge était de 40,8 ans. Parmi eux, 95,3 % répondaient à au moins un critère de sélection permettant l'application de définitions de cas pour la surveillance des maladies chroniques. Cette proportion variait avec l'âge : de 90,1 % chez les Québécois de 19 ans et moins à 99,3 % chez ceux de 65 ans et plus. Conclusion Le SISMACQ permet la production de données, à l'échelle de la population, sur le fardeau de plusieurs maladies chroniques, sur l'utilisation des services de santé et sur la consommation de médicaments. Il rend possible l'étude intégrée de la combinaison de plusieurs maladies, une approche jusqu'à présent rarement mise en oeuvre dans un contexte de surveillance populationnelle. Le SISMACQ répond aux attributs essentiels d'un système de surveillance et aide à la diffusion de l'information auprès des décideurs en vue d'actions en santé publique.

Background The surveillance of heart failure (HF) is currently conducted using either survey or hospital data, which have many limitations. Because Canada is collecting medical information in administrative health data, the present study seeks to propose methods for the national surveillance of HF using linked population-based data. Methods Linked administrative data from 5 Canadian provinces were analyzed to estimate prevalence, incidence, and mortality rates for persons with HF between 1996/1997 and 2008/2009 using 2 case definitions: (1) 1 hospitalization with an HF diagnosis in any field (H_Any) and (2) 1 hospitalization in any field or at least 2 physician claims within a 1-year period (H_Any_2P). One hospitalization with an HF diagnosis code in the most responsible diagnosis field (H_MR) was also compared. Rates were calculated for individuals aged ≥40 years. Results In 2008/2009, combining the 5 provinces (approximately 82% of Canada's total population), both age-standardized HF prevalence and incidence were underestimated by 39% and 33%, respectively, with H_Any when compared with H_Any_2P. Mortality was higher in patients with H_MR compared with H_Any. The degree of underestimation varied by province and by age, with older age groups presenting the largest differences. Prevalence estimates were stable over the years, especially for the H_Any_2P case definition. Conclusions The prevalence and incidence of HF using inpatient data alone likely underestimates the population rates by at least 33%. The addition of physician claims data is likely to provide a more inclusive estimate of the burden of HF in Canada.

Background: Clopidogrel is widely used to prevent atherothrombotic events. Federal standards regulate bioequivalence of generic and brand-name drugs through comparative bioavailability studies but does not regulate clinical equivalence nor tolerability in “real-life” settings. We evaluated the impact of the generic clopidogrel commercialization on some adverse events: emergency room consultations (ER) or hospitalizations. Methods: This is an interrupted time series analysis using the Quebec Integrated Chronic Disease Surveillance System. Rates of adverse events for clopidogrel users (n=75,130) aged ≥ 66 years were calculated monthly, 12 months before and 12 months after generics commercialization. Periods before and after generics commercialization were compared by negative binomial segmented regression models for all users with a specific variable for generic and brand-name users after generics commercialization. Results: Generic clopidogrel analogs (n=6) were commercialized in 2012. There was an approximated monthly mean rate of 157 adverse events per 1000 brand-name and generic users-month. After generics commercialization, there was an immediate increase in rates of adverse events for generic vs. brand-name users (22 vs. 2%, p < 0.0001, Figure 1). This was explained by increased rates of ER (+22%) and hospitalizations (+20%) the month of generic clopidogrel commercialization. Hospitalization trend up to 1 year after generics commercialization was stable for generic users but reduced for brand-name users (-0.9 vs. -2.9%, p = 0.01), while ER trends were comparable (-1.1 vs. -1.8%, p = 0.2443). Conclusion: Among generic clopidogrel users, increased rates of ER and hospitalizations were observed soon after generics commercialization. The trend of hospitalizations was also affected following generic clopidogrel commercialization. Risk and survival analysis studies controlling for potential confounding are required to better characterize generic substitution.

Background: Substitution from brand-name to generic drugs is one way to reduce costs of pharmacological treatments. Generic drugs licensing is obtained through comparative bioavailability studies for which a variation of up to 20% is generally accepted. However, “real-life” efficacy and tolerance of generic drugs are not studied prior to commercialization. We aimed to evaluate the impact of brand-name to generic losartan, valsartan or candesartan substitution on serious adverse events (hospitalizations, emergency room consultations [ER] or mortality). Method: Three cohorts of persistent angiotensin II receptor blockers (ARB) users (losartan [brand-name and 8 generics], valsartan [brand-name and 5 generics] and candesartan [brand-name and 3 generics])aged ≥ 66 years were constituted using data from the Quebec Integrated Chronic Disease Surveillance System. Generic exposition was determined by substitution time-distribution matching. Time free of adverse events up to 365 days after the onset of generic exposition was compared between groups by survival analysis using Cox regression models adjusted for age, sex, comorbidities, concomitant treatments, socioeconomic status, previous brand-name drug, healthcare resources utilization and prescriber’s speciality, to provide hazard ratio (HR). Sensitivity analysis including non-persistent users was also conducted. Results: Within cohorts (losartan, n = 15,469; valsartan, n = 17,205; and candesartan, n = 25,008), proportions of exposed to generic substitution vs. unexposed who had at least one adverse event were respectively: 35% vs. 25%, 34% vs. 28% and 31% vs. 27% (all, p p < 0.0001]; 1.22 [ p < 0.0001] and 1.08 [ p = 0.0317]) and ER (HR: 1.55; 1.20 and 1.16, all = p < 0.0001). Regarding mortality, HR were respectively: 0.63 [ p = 0.1456]; 0.95 [ p = 0.8487] and 0.43 [ p < 0.0001]). Survival was not significantly different for exposed to generic losartan and valsartan substitution. However, even if the time free of hospitalizations and ER was 8% and 16% shorter for patients exposed to generic candesartan substitution, their survival was 2.3 times better when compared to patients who remained on brand-name candesartan (unexposed). Sensitivity analysis yield similar results. Conclusion: Substitution to generic antihypertensive drugs is associated with a significantly reduced delay before hospitalizations and ER for the three ARBs but a better survival for patients exposed to generic candesartan substitution only. Better bioavailability of generics versions of candesartan or differences in health cares between users could explain these differences.

Background The theory that elevated iron stores can induce vascular injury and ischemia remains controversial. We conducted a cohort study of the effect of blood donation on the risk of coronary heart disease (CHD) by taking advantage of the quasi-random exclusion of donors who obtained a falsely reactive test for a transmissible disease (TD) marker. Study Design and Methods Whole blood donors who were permanently disqualified because of a false-reactive test between 1990 and 2007 in the province of Quebec were compared to donors who remained eligible, matched for baseline characteristics. The incidence of CHD after entry into the study was determined through hospitalization and death records. We compared eligible and disqualified donors using an “intention-to-treat” framework. Results Overall, 12,357 donors who were permanently disqualified were followed for 124,123 person-years of observation, plus 50,889 donors who remained eligible (516,823 person-years). On average, donors who remained eligible made 0.36 donation/year during follow-up and had an incidence of hospitalizations or deaths attributable to CHD of 3.60/1000 person-years, compared to 3.52 among permanently disqualified donors (rate ratio, 1.02; 95% confidence interval, 0.92-1.13). Conclusion Donors who remained eligible did not have a lower risk of CHD, compared to donors who were permanently disqualified due to a false-reactive TD marker. Because of the quasi-random nature of false-reactive screening tests, this natural experiment has a level of validity approaching that of a randomized trial evaluating the effect of regular blood donation on CHD risk. These results do not support the iron hypothesis.

Background: There are limited data on the effects of climate and air pollutant exposure on heart failure (HF) within taking into account individual and contextual variables. Objectives: We measured the lag effects of temperature, relative humidity, atmospheric pressure and fine particulate matter (PM2.5) on hospitalizations and deaths for HF in elderly diagnosed with this disease on a 10-year period in the province of Quebec, Canada. Methods: Our population-based cohort study included 112,793 elderly diagnosed with HF between 2001 and 2011. Time dependent Cox regression models approximated with pooled logistic regressions were used to evaluate the 3- and 7-day lag effects of daily temperature, relative humidity, atmospheric pressure and PM2.5 exposure on HF morbidity and mortality controlling for several individual and contextual covariates. Results: Overall, 18,309 elderly were hospitalized and 4297 died for the main cause of HF. We observed an increased risk of hospitalizations and deaths for HF with a decrease in the average temperature of the 3 and 7days before the event. An increase in atmospheric pressure in the previous 7days was also associated with a higher risk of having a HF negative outcome, but no effect was observed in the 3-day lag model. No association was found with relative humidity and with PM2.5 regardless of the lag period. Conclusions: Lag effects of temperature and other meteorological parameters on HF events were limited but present. Nonetheless, preventive measures should be issued for elderly diagnosed with HF considering the burden and the expensive costs associated with the management of this disease. Keywords: Heart failure, Elderly, Climate changes, Fine particulate matter, Lag effect, Canada

This study aimed at determining the role of proximity to specific types of green spaces (GSes) as well as their spatial location in the relationship with the most morbid cardiovascular diseases (CVD) and diabetes. We measured the accessibility to various types of GS and used a cross-sectional approach at census Dissemination Area (DA) levels in the Montreal and Quebec City metropolitan zones for the period 2006-2011. Poisson and negative binomial regression models were fitted to quantify the relationship between distances to specific types of GS and CVD morbidity as well as some risk factors (diabetes and hypertension) while controlling for several social and environmental confounders. GSes that have sports facilities showed a significant relationship to cerebrovascular diseases: the most distant population had an 11% higher prevalence rate ratio (PRR) compared to the nearest, as well as higher diabetes risk (PRR 9%) than the nearest. However, the overall model performance and the understanding of the role of GSes with sport facilities may be substantially achieved with lifestyle factors. Significantly higher prevalence of diabetes and cerebrovascular diseases as well as lower access to GSes equipped with sports facilities were found in suburban areas. GSes can advantageously be used to prevent some CVDs and their risk factors, but there may be a need to reconsider their types and location.

Introduction Studies suggest that hypertension is more prevalent in the most deprived. Our objective was to examine the association between incident hypertension and deprivation in Quebec based on different modes of case identification, using two administrative databases. Methods We identified new incident cases of hypertension in 2006/2007 in the population aged 20 years plus. Socio-economic status was determined using a material and social deprivation index. Negative binomial regression analyses were carried out to examine the association between incident hypertension and deprivation, adjusting for several covariates. Results We found a positive and statistically significant association between material deprivation and incident hypertension in women, irrespective of the identifying database. Using the hospitalization database, the incidence of hypertension increased for both sexes as deprivation increased, except for social deprivation in women. However, whether using the physician billing database or the validated definition of hypertension obtained by combining data from the two databases, the incidence of hypertension decreased overall as deprivation increased. Conclusion Associations between hypertension and deprivation differ based on the database used: they are generally positively associated with the hospitalization database and inversely with the standard definition and the physician billing database, which suggests a consultation bias in favour of the most socio-economically advantaged.

Contexte Selon diverses études, l’hypertension artérielle serait plus fréquente chez les personnes les plus défavorisées. Notre objectif était d’examiner l’association entre l’incidence de l’hypertension et la défavorisation au Québec en nous fondant sur divers modes d’identification des cas, à l’aide de deux fichiers administratifs. Méthodologie Nous avons recensé les nouveaux cas d’hypertension artérielle déclarés en 2006-2007 chez les personnes de 20 ans et plus. Nous avons déterminé le statut socioéconomique de ces personnes en utilisant des indices de défavorisation matérielle et sociale. Nous avons effectué des analyses de régression binomiale négative pour étudier le lien entre le taux d’incidence de l’hypertension et le niveau de défavorisation matérielle ou sociale, en tenant compte de diverses covariables. Résultats Nous avons trouvé une association positive et statistiquement significative entre la défavorisation matérielle et l’incidence de l’hypertension chez les femmes, et ce, peu importe le fichier administratif utilisé pour identifier les cas. En utilisant le fichier des hospitalisations, nous avons observé que l’incidence de l’hypertension croît chez les deux sexes à mesure que le niveau de défavorisation augmente, sauf pour la défavorisation sociale chez les femmes. Toutefois, que ce soit en utilisant le fichier des services médicaux rémunérés à l’acte ou en utilisant la définition validée de l’hypertension obtenue en associant les données des deux fichiers administratifs, nous avons constaté que l’incidence de l’hypertension décroît à mesure que le niveau de défavorisation augmente. Conclusion Les associations observées entre l’hypertension et la défavorisation varient en fonction du fichier administratif utilisé : de façon générale, on observe une association positive lorsqu’on utilise le fichier des hospitalisations, mais négative lorsqu’on utilise la définition standard et le fichier des services médicaux rémunérés à l’acte, ce qui laisse croire qu’il existe un biais de consultation favorisant les personnes les plus avantagées sur le plan socioéconomique.

Background Socioeconomic status (SES) and area of residence are known to impact access to invasive cardiac procedures. Low SES adversely affects long-term mortality after acute myocardial infarction (AMI). Most of the data were derived from private healthcare systems. Our objectives were to evaluate the effects of SES and area of residence on access to coronary angiography, revascularization and mortality after a first AMI in a publicly-funded healthcare system with a high supply of catheterization facilities. Methods Quebec administrative databases were used to identify all patients with a first AMI between 1997 and 2001. The SES was determined with the population deprivation index, which has 2 dimensions: material and social. Six-month access to angiography, revascularization and 1-year mortality were considered in proportional hazards survival regression analyses measuring the effect of deprivation and the geographical area of residence, accounting for several other covariates. Results The study cohort consisted of 50,242 patients. The most materially and socially deprived patients had a 16% (95% confidence interval [CI], 1.08-1.25) and 13% (95% CI, 1.05-1.21) relative increased hazard of dying within 1 year respectively compared with the most privileged subjects. This mortality gradient could not be explained by meaningful differences in access to angiography or revascularization. Geography did not influence access to revascularization procedures. Conclusions Despite universal healthcare system, SES measured with a material and social deprivation index, had significant adverse effect on 1-year mortality after a first AMI. Such findings were not explained by lower access to coronary angiography or revascularization.

Background: Hypertension is a leading risk factor for cardiovascular diseases. Our objectives were to examine the prevalence and incidence of diagnosed hypertension in Canada and compare mortality among people with and without diagnosed hypertension. Methods: We obtained data from linked health administrative databases from each province and territory for adults aged 20 years and older. We used a validated case definition to identify people with hypertension diagnosed between 1998/99 and 2007/08. We excluded pregnant women from the analysis. Results: This retrospective population-based study included more than 26 million people. In 2007/08, about 6 million adults (23.0%) were living with diagnosed hypertension and about 418 000 had a new diagnosis. The age-standardized prevalence increased significantly from 12.5% in 1998/99 to 19.6% in 2007/08, and the incidence decreased from 2.7 to 2.4 per 100. Among people aged 60 years and older, the prevalence was higher among women than among men, as was the incidence among people aged 75 years and older. The prevalence and incidence were highest in the Atlantic region. For all age groups, all-cause mortality was higher among adults with diagnosed hypertension than among those without diagnosed hypertension. Interpretation: The overall prevalence of diagnosed hypertension in Canada from 1998 to 2008 was high and increasing, whereas the incidence declined during the same period. These findings highlight the need to continue monitoring the effectiveness of efforts for managing hypertension and to enhance public health programs aimed at preventing hypertension.

Background Many studies have relied on administrative data to identify patients with heart failure (HF). Objective To systematically review studies that assessed the validity of administrative data for recording HF. Methods English peer-reviewed articles (1990 to 2008) validating International Classification of Diseases (ICD)-8, -9 and -10 codes from administrative data were included. An expert panel determined which ICD codes should be included to define HF. Frequencies of ICD codes for HF were calculated using up to the 16 diagnostic coding fields available in the Canadian hospital discharge abstract during fiscal years 2000/2001 and 2005/2006. Results Between 1992 and 2008, more than 70 different ICD codes for defining HF were used in 25 published studies. Twenty-one studies validated hospital discharge abstract data; three studies validated physician claims and two studies validated ambulatory care data. Eighteen studies reported sensitivity (range 29% to 89%). Specificity and negative predictive value were greater than 70% across 17 studies. Nineteen studies reported positive predictive values (range 12% to 100%). Ten studies reported kappa values (range 0.39 to 0.84). For Canadian hospital discharge data, ICD-9 and -10 codes 428 and I50 identified HF in 5.50% and 4.80% of discharge records, respectively. Additional HF-related ICD-9 and -10 codes did not impact HF prevalence. Conclusion The ICD-9 and -10 codes 428 and I50 were the most commonly used to define HF in hospital discharge data. Validity of administrative data in recording HF varied across the studies and data sources that were assessed.

Background: Floods represent a serious threat to human health beyond the immediate risk of drowning. There is few data on the potential link between floods and direct consequences on health such as on cardiovascular health. This study aimed to explore the impact of one of the worst floods in the history of Quebec, Canada on acute cardiovascular diseases (CVD). Methods: A cohort study with a time series design with multiple control groups was built with the adult population identified in the Quebec Integrated Chronic Disease Surveillance System. A geographic information system approach was used to define the study areas. Logistic regressions were performed to compare the occurrence of CVD between groups. Results: The results showed a 25%–27% increase in the odds in the flooded population in spring 2011 when compared with the population in the same area in springs 2010 and 2012. Besides, an increase up to 69% was observed in individuals with a medical history of CVD. Conclusion: Despite interesting results, the association was not statistically significant. A possible explanation to this result can be that the population affected by the flood was probably too small to provide the statistical power to answer the question, and leaves open a substantial possibility for a real and large effect.

Background— We sought to investigate the use of a new parameter, the projected effective orifice area (EOA proj ) at normal transvalvular flow rate (250 mL/s), to better differentiate between truly severe (TS) and pseudo-severe (PS) aortic stenosis (AS) during dobutamine stress echocardiography (DSE). Changes in various parameters of stenosis severity have been used to differentiate between TS and PS AS during DSE. However, the magnitude of these changes lacks standardization because they are dependent on the variable magnitude of the transvalvular flow change occurring during DSE. Methods and Results— The use of EOA proj to differentiate TS from PS AS was investigated in an in vitro model and in 23 patients with low-flow AS (indexed EOA 2 /m 2 , left ventricular ejection fraction ≤40%) undergoing DSE and subsequent aortic valve replacement. For an individual valve, EOA was plotted against transvalvular flow (Q) at each dobutamine stage, and valve compliance (VC) was derived as the slope of the regression line fitted to the EOA versus Q plot; EOA proj was calculated as EOA proj =EOA rest +VC×(250−Q rest ), where EOA rest and Q rest are the EOA and Q at rest. Classification between TS and PS was based on either response to flow increase (in vitro) or visual inspection at surgery (in vivo). EOA proj was the most accurate parameter in differentiating between TS and PS both in vitro and in vivo. In vivo, 15 of 23 patients (65%) had TS and 8 of 23 (35%) had PS. The percentage of correct classification was 83% for EOA proj and 91% for indexed EOA proj compared with percentages of 61% to 74% for the other echocardiographic parameters usually used for this purpose. Conclusions— EOA proj provides a standardized evaluation of AS severity with DSE and improves the diagnostic accuracy for distinguishing TS and PS AS in patients with low-flow, low-gradient AS.

Background— The prosthesis used for aortic valve replacement (AVR) can be too small in relation to body size, thus causing valve prosthesis-patient mismatch (PPM) and abnormally high transvalvular pressure gradients. This study examined if there is a relation between PPM and short-term mortality after operation. Methods and Results— The indexed valve effective orifice area (EOA) was estimated for each type and size of prosthesis being implanted in 1266 consecutive patients and used to define PPM as not clinically significant if >0.85 cm 2 /m 2 , as moderate if >0.65 cm 2 /m 2 and ≤0.85 cm 2 /m 2 , and as severe if ≤0.65 cm 2 /m 2 ; it was correlated with 30-day mortality and compared with other relevant variables. Moderate or severe PPM was present in 38% of patients. Thirty-day mortality was 4.6% (58/1266 patients) and the strongest independent predictors in multivariate analysis were left ventricular ejection fraction P =0.007), infectious endocarditis ( P =0.002), emergent/salvage operation ( P =0.002), cardiopulmonary bypass time >120 minutes ( P =0.001), and PPM ( P =0.003). Relative risk of mortality was increased 2.1-fold (95% confidence interval, 1.2 to 3.7) in patients with moderate PPM and 11.4-fold (4.4 to 29.5) in those with severe PPM. Moreover, risk of mortality for every category of PPM was higher in patients with a left ventricular ejection fraction Conclusion— PPM is a strong and independent predictor of short-term mortality among patients undergoing AVR, and its impact is related both to its degree of severity and the status of left ventricular function. In contrast to other risk factors, moderate-severe PPM can be largely avoided with the use of a prospective strategy at the time of operation.

Background: There is increasing evidence on the cardiovascular effects of transportation noise in European countries, but a notable paucity of studies from other countries such as those in North Am...

OBJECTIVES: Hypertension is a major risk factor for cardiovascular diseases. Nearly one adult in four was diagnosed with hypertension in 2007-2008 in Canada. One of the objectives of this study was to determine whether the prevalence of hypertension in Quebec as assessed using administrative data is comparable to that specifically measured, especially for the elderly population. METHODS: Trends in prevalence, incidence and mortality were examined using the Quebec Integrated Chronic Disease Surveillance System built from grouping numerous administrative databases from 1996-1997 to 2009-2010. Blood pressure measurements, hypertension prevalence, awareness and control were obtained in 1,706 Quebecers in the combined cycles of the Canadian Health Measures Survey. RESULTS: Using administrative databases, 23.6% [95% confidence interval, 23.5-23.6] of the Quebec population (n=1,433,400) aged ≥20 years was diagnosed with hypertension in 2009-2010, an increase of 32.1% compared to 2000 2001. The incidence decreased by 27.3%. Among people aged ≥65 years, the prevalence rose to 69.0% [95% CI: 68.8 69.2] in women and 61.7% [95% CI: 61.5-61.9] in men. For people aged 20-79 years, the prevalence of hypertension was lower with the administrative data compared to the survey (20.2% and 23.1%, respectively). The level of awareness, treatment and control were 84.3%, 83.1% and 67.9%, respectively. CONCLUSION: The prevalence of hypertension derived from administrative data is comparable to that obtained with a health measured survey. Elderly women (≥65 years) are a very high-risk subgroup. The levels of awareness, treatment and control of hypertension in Quebec are very high.