Population-based Health Administrative Data Research Articles

Uptake and cardiac events of COVID-19 vaccinations among Canadian youth and young adults.

Few studies have examined population-level data of the COVID-19 original and bivalent vaccine on its uptake and potential side effects. We used population-based health administrative data from Jan 2021-Feb 2023 to identify Ontario residents aged 12-35 years old to calculate their rates of COVID-19 vaccine uptake and vaccine-related cardiac events (myocarditis and pericarditis). Multivariable Cox, logistic, and negative binomial regression analyses were used to adjust for covariates. Hazard ratios (HR) were reported with 95% confidence intervals (CI). The study population included 5,012,721 individuals. Comparing to the general population, those with chronic diseases were associated with 13-37% higher rates of vaccine uptake and 1.39-2.27 times higher odds of receiving booster doses. Overall, post-vaccination cardiac event incidence rates ranged from 3-12 per 100,000 persons. Compared to the general population, the incidence rate of cardiac events among those with asthma and allergic diseases was significantly higher, 3.7 events per 100,000 persons. Compared to the general population, those with asthma and/or allergic diseases had significantly higher associated likelihoods of a cardiac event (HR = 1.31, 95% CI: 1.08-1.57). Females, adults, and those with prior COVID-19 infections had decreased odds of cardiac events after 2nd vaccine doses. No significant differences in post-vaccine cardiac events were detected between original and bivalent doses. This Canadian population-based study reported substantially higher rates of vaccine uptake and a very rare incidence of temporally associated post-vaccination cardiac events. While substantially smaller than the benefits of vaccination, our results indicated a continued small risk of cardiac side effects from bivalent COVID-19 vaccines in individuals with comorbidities.

Real-world cost-effectiveness of panel-based genomic testing to inform therapeutic decisions for metastatic colorectal cancer

BackgroundMutations in KRAS and NRAS are associated with a lack of response to cetuximab and panitumumab, two biologics used for third-line therapy of metastatic colorectal cancer (mCRC). In British Columbia, Canada, eligibility for cetuximab or panitumumab was first based on single-gene KRAS testing. OncoPanel, a multi-gene next-generation sequencing panel with both KRAS and NRAS, was introduced in 2016. Our objective was to estimate the real-world cost-effectiveness of OncoPanel versus to single-gene KRAS testing to inform eligibility for cetuximab or panitumumab in mCRC. MethodsUsing population-based administrative health data, we identified a cohort of mCRC patients who had received a KRAS or OncoPanel test, and completed prior chemotherapy in 2010–2019. We matched KRAS- and OncoPanel-tested patients (1:1) using genetic matching to balance baseline covariates. Mean and incremental 3-year costs, survival, and quality-adjusted survival were estimated using inverse-probability-of-censoring weighting and bootstrapping. We conducted scenario-based sensitivity analysis for key costs and assumptions. FindingsAll OncoPanel-tested cases (n=371) were matched to a KRAS-tested comparator. In the KRAS and OncoPanel groups, respectively, 55·8 % and 41·2 % of patients were potentially eligible for cetuximab or panitumumab based on mutation status. Incremental cost and effectiveness of OncoPanel were $72 (95 % CI: −6387, 6107), −0·004 life-years (95 % CI: −0·119, 0·113), and −0·011 quality-adjusted life-years (95 % CI: −0·094, 0·075). Reductions in systemic therapy costs were offset by increased costs in other resources. Results were moderately sensitive to time horizon and changes in testing or treatment cost. InterpretationThe use of OncoPanel resulted in more precise targeting of cetuximab and panitumumab, but there was no change in incremental cost or quality-adjusted survival. Understanding the balance of costs achieved in practice can provide insight into the effect of future changes in testing policy, test cost, treatment eligibility, or drug prices in this setting.

Patient-Physician Sex Discordance and "Before Medically Advised" Discharge from Hospital: A Population-Based Retrospective Cohort Study.

Patient-physician sex discordance (when patient sex does not match physician sex) has been associated with reduced clinical rapport and adverse outcomes including post-operative mortality and unplanned hospital readmission. It remains unknown whether patient-physician sex discordance is associated with "before medically advised" hospital discharge (BMA discharge; commonly known as discharge "against medical advice"). To evaluate whether patient-physician sex discordance is associated with BMA discharge. Retrospective cohort study using 15years (2002-2017) of linked population-based administrative health data for all non-elective, non-obstetrical acute care hospitalizations from British Columbia, Canada. All individuals with eligible hospitalizations during study interval. Exposure: patient-physician sex discordance. BMA discharge (primary), 30-day hospital readmission or death (secondary). We identified 1,926,118 eligible index hospitalizations, 2.6% of which ended in BMA discharge. Among male patients, sex discordance was associated with BMA discharge (crude rate, 4.0% vs 2.9%; adjusted odds ratio [aOR] 1.08; 95%CI 1.03-1.14; p = 0.003). Among female patients, sex discordance was not associated with BMA discharge (crude rate, 2.0% vs 2.3%; aOR 1.02; 95%CI 0.96-1.08; p = 0.557). Compared to patient-physician sex discordance, younger patient age, prior substance use, and prior BMA discharge all had stronger associations with BMA discharge. Patient-physician sex discordance was associated with a small increase in BMA discharge among male patients. This finding may reflect communication gaps, differences in the care provided by male and female physicians, discriminatory attitudes among male patients, or residual confounding. Improved communication and better treatment of pain and opioid withdrawal may reduce BMA discharge.

Physician Financial Incentives to Reduce Unplanned Hospital Readmissions: A Propensity Score Weighted Cohort Study

BackgroundUnplanned hospital readmissions are associated with adverse patient outcomes and substantial healthcare costs. It remains unknown whether physician financial incentives for enhanced discharge planning can reduce readmission risk. MethodsIn 2012, policymakers in British Columbia, Canada, introduced a $75 fee-for-service physician payment to incentivize enhanced discharge planning (the “G78717” fee code). We used population-based administrative health data to compare outcomes among G78717-exposed and G78717-unexposed patients. We identified all nonelective hospitalizations potentially eligible for the incentive over a 5-year study interval. We examined the composite risk of unplanned readmission or death and total direct healthcare costs accrued within 30 days of discharge. Propensity score overlap weights and adjustment were used to account for differences between exposed and unexposed patients. ResultsA total of 5262 of 24,787 G78717-exposed and 28,096 of 136,541 unexposed patients experienced subsequent unplanned readmission or death, suggesting exposure to the G78717 incentive did not reduce the risk of adverse outcomes after discharge (crude percent, 21.1% vs 20.6%; adjusted odds ratio, 0.97; 95% CI, 0.93-1.01; P = .23). Mean direct healthcare costs within 30 days of discharge were $3082 and $2993, respectively (adjusted cost ratio, 1.00; 95% CI, 0.95-1.05; P = .93). ConclusionsA physician financial incentive that encouraged enhanced hospital discharge planning did not reduced the risk of readmission or death, and did not significantly decrease direct healthcare costs. Policymakers should consider the baseline prevalence and effectiveness of enhanced discharge planning, the magnitude and design of financial incentives, and whether auditing of incentivized activities is required when implementing similar incentives elsewhere. Trial RegistrationClinicalTrials.gov ID, NCT03256734

Sociodemographic Factors and Trends in Bronchiolitis-Related Emergency Department Visit and Hospitalization Rates

Bronchiolitis is the most common and most cumulatively expensive condition in pediatric hospital care. Few population-based studies have examined health inequalities in bronchiolitis outcomes over time. To examine trends in bronchiolitis-related emergency department (ED) visit and hospitalization rates by sociodemographic factors in a universally funded health care system. This repeated cross-sectional cohort study was performed from April 1, 2004, to March 31, 2022, using population-based health administrative data from children younger than 2 years in Ontario, Canada. Bronchiolitis ED visit and hospitalization rates per 1000 person-years reported for the equity stratifiers of sex, residence location (rural vs urban), and material resources quintile. Trends in annual rates by equity stratifiers were analyzed using joinpoint regression and estimating the average annual percentage change (AAPC) with 95% CI and the absolute difference in AAPC with 95% CI from April 1, 2004, to March 31, 2020. Of 2 921 573 children included in the study, 1 422 088 (48.7%) were female and 2 619 139 (89.6%) lived in an urban location. Emergency department visit and hospitalization rates were highest for boys, those with rural residence, and those with least material resources. There were no significant between-group absolute differences in the AAPC in ED visits per 1000 person-years by sex (female vs male; 0.22; 95% CI, -0.92 to 1.35; P = .71), residence (rural vs urban; -0.31; 95% CI -1.70 to 1.09; P = .67), or material resources (quintile 5 vs 1; -1.17; 95% CI, -2.57 to 0.22; P = .10). Similarly, there were no significant between-group absolute differences in the AAPC in hospitalizations per 1000 person-years by sex (female vs male; 0.53; 95% CI, -1.11 to 2.17; P = .53), residence (rural vs urban; -0.62; 95% CI, -2.63 to 1.40; P = .55), or material resources (quintile 5 vs 1; -0.93; 95% CI -3.80 to 1.93; P = .52). In this population-based cohort study of children in a universally funded health care system, inequalities in bronchiolitis ED visit and hospitalization rates did not improve over time.

Maternal diabetes and fracture risk in offspring: a population-based analysis.

Factors affecting intrauterine environment exerts influence on skeletal health and fracture risk in later life. Diabetes during pregnancy is known to influence birth weight and is associated with fetal overgrowth. However, the effects of maternal diabetes on fracture risk in offspring is unknown. This study was aimed to evaluate the association between maternal diabetes and fracture risk in offspring. Using population-based administrative health data for Manitoba, Canada, we identified deliveries complicated by gestational diabetes and type 2 diabetes between April 1, 1980, and March 31, 2020. The cohort was followed for a median of 15.8yr. The primary outcome was any incident fracture in offspring. Secondary outcomes were long bone upper extremity fracture, long bone lower extremity fracture, vertebral fracture, and any non-trauma fractures. Cox proportional hazard regression models were used to estimate fracture risk in offspring by maternal diabetes status adjusted for relevant covariates. Of the 585 176 deliveries, 26 397 offspring were born to women with diabetes (3.0% gestational diabetes and 1.5% type 2 diabetes), and 558 779 were born to women without diabetes. The adjusted risk for any fracture was 7% (hazard ratio, 1.07; 95% CI, 2.7-11.5%) higher in the offspring of mothers with diabetes than offspring of mothers without diabetes. Types of fractures were similar between the 2 groups with a predominance of long bone upper extremity fractures. In conclusion, maternal diabetes was associated with a modest increase in fracture risk in offspring. Longitudinal prospective studies are needed to understand intrauterine and postnatal factors that may influence fracture risk in the offspring of mothers with diabetes.

Evaluating the Association between the Implementation of the PoET (Prevention of Error-Based Transfers) Southwest Spread Project and Palliative Care Provision: A Quasi-Experimental Matched Cohort Study Using Population-Level Health Administrative Data

ObjectivesThe PoET (Prevention of Error-based Transfers) project seeks to align long-term care (LTC) home informed consent practices to existing legislation, thereby reducing consent-related error-based transfers to acute care. We sought to measure changes in resident-level palliative care provision after participating in the PoET Southwest Spread Project (PSSP), and to identify patient and LTC home characteristics associated with palliative care provision. DesignQuasi-experimental matched (1:1 ratio) cohort study design using linked population-based health administrative data. SettingSixty LTC homes (PSSP = 30; Control = 30) in Ontario, Canada, from November 2019 to December 2021. MethodsWe matched 30 PSSP to 30 control homes and described incidence rates for resident-level palliative care provision (ie, physician palliative care encounters and palliative medication prescriptions) during the 7-month postimplementation period. We used generalized linear mixed models to evaluate the association between PSSP implementation and palliative care provision during the postimplementation period. We adjusted for resident-level characteristics (ie, age, sex, comorbidity status) and home-level characteristics (ie, rurality status, profit model, COVID-19 impact). We identified a decedent subcohort to measure palliative care provision patterns during the last 2 months of life. ResultsWe captured a matched cohort of 8894 residents (PSSP = 4103; Control = 4791). Incidence rates of palliative care encounters increased during the postimplementation period for PSSP (82.6 to 85.4 per 100 person-months) but not for control residents (68.8 to 65.3 per 100 person-months). After adjusting for key covariates, PSSP exposure was associated increased palliative care provision (incidence rate ratio 2.47, 95% CI 2.31-2.64) and palliative care medication prescription (1.16, 95% CI 1.12-1.20). Larger home size, certain health regions, and higher number of comorbidities were associated with increased physician palliative care encounters. Conclusions and ImplicationsBy promoting correct informed consent practices in LTC, PSSP participation increased palliative care provision for PSSP LTC residents across all settings.

Distinguishing Primary Prevention From Secondary Prevention Implantable Cardioverter Defibrillators Using Administrative Health and Cardiac Device Registry Data

BackgroundAdministrative health data and cardiac device registries can be used to empirically evaluate outcomes and costs after implantable cardioverter defibrillator (ICD) implantation. These datasets often have incomplete information on the indication for implantation (primary vs secondary prevention of sudden cardiac death). MethodsWe used 16 years of population-based cardiac device registry and administrative health data from British Columbia, Canada, to derive and internally validate statistical models that predict the likely indication for ICD implantation. We used chart review data as the reference standard for ICD indication in the Cardiac Device Registry database (CDR; 2004-2012 [Cardiac Services BC]) and nonmissing indication as the reference standard in the Heart Information System registry database (HEARTis; 2013-2019 [Cardiac Services BC]). We created 3 logistic regression prediction models in each database: one using only registry data, one using only administrative data, and one using both registry and administrative data. We assessed the predictive performance of each model using standard metrics after optimism correction with 200 bootstrap resamples. ResultsModels that used registry data alone demonstrated excellent predictive performance (sensitivity ≥ 89%; specificity ≥ 87%). Models that used only administrative data performed well (sensitivity ≥ 84%; specificity ≥ 70%). Models that used both registry and administrative data showed modest gains over those that used registry data alone (sensitivity ≥ 90%; specificity ≥ 89%). ConclusionsAdministrative health data and cardiac device registry data can distinguish secondary prevention ICDs from primary prevention ICDs with acceptable sensitivity and specificity. Imputation of missing ICD indication might make these data resources more useful for research and health system monitoring.

Mortality of Pediatric Surgical Lung Biopsies in Ontario, Canada, 2000-2019.

Rationale: Surgical lung biopsies are often required for the definitive diagnosis of nonmalignant pediatric diffuse lung diseases; however, the literature on mortality after surgical lung biopsy in pediatric patients is sparse. Objectives: To determine the 30-day postoperative mortality rate after surgical lung biopsies for nonmalignant lung disease in pediatric patients in Ontario, Canada, and to identify risk factors associated with mortality. Methods: We performed an observational cohort study using population-based health administrative data available from ICES in Ontario, Canada, from 2000 to 2019. Cases were identified using the Canadian Classification of Health Interventions. Inclusion criteria were first surgical lung biopsies between 2000 and 2019 and age <18 years. Individuals with lung cancer, lung transplant, or missing data were excluded. A multivariable logistic regression model with generalized estimating equation was used to estimate the 30-day odds of mortality after surgical lung biopsy and to identify patient characteristics associated with increased mortality while accounting for clustering by hospital. Results: We identified 1,474 pediatric patients who underwent surgical lung biopsy in Ontario between 2000 and 2019. The overall mortality rates decreased over the study duration from 6.6% (2000-2004) to 3.0% (2015-2019). The study cohort for multivariate analyses consisted of 1,342 patients who had complete data. The pediatric mortality 30 days after surgical lung biopsy was 5.1% but was <1% in elective cases. Risk factors for increased mortality included open surgical lung biopsy (vs. video-assisted) (odds ratio [OR], 13.13; 95% confidence interval [CI], 3.76, 45.87; P < 0.001), nonelective procedure (OR, 11.74; 95% CI, 3.51, 39.27; P < 0.001), younger age (<3 mo) (OR, 6.04; 95% CI, 2.40, 15.22; P < 0.001), and higher comorbidity score (OR, 1.15; 95% CI, 1.05, 1.26; P = 0.003). Conclusions: Pediatric mortality postsurgical lung biopsy is not insignificant, particularly in nonelective procedures. Other important risk factors to consider when pursuing pathologic diagnosis include surgical approach, younger age, and higher comorbidity.

Patterns in COVID-19 vaccination among children aged 5–11 years in Alberta, Canada: Lessons for future vaccination campaigns

ObjectivesIn Alberta, Canada, the COVID-19 vaccination program for children aged 5–11 years was launched on November 26, 2021. Our objectives were to determine the cumulative vaccine coverage, stratified by age, during the first thirteen months of vaccine availability, and investigate factors associated with vaccine uptake. Study designThis retrospective cohort study used population-based administrative health data. MethodsWe determined cumulative vaccine coverage among 5–11 year olds, stratified by year of age, during the first thirteen months of vaccine availability and used a modified Poisson regression to evaluate factors associated with vaccine uptake. ResultsOf 377,103 eligible children, 44.8 % (n = 168,761) received one or more doses of COVID-19 vaccine during the study period (9.7 % received only one dose, while 35.1 % received 2 doses). Almost 90 % of initial doses were received within the first two months of vaccine availability. We found a step-wise relationship between increasing child age and higher vaccine coverage. ConclusionsPlateaued vaccine uptake indicates a need to adapt programmatic efforts to encourage parents to act on positive vaccination intentions, and reach the large contingent of parents who have reported that they remain undecided. In order to promote vaccine uptake, messaging around vaccine safety and need should be tailored to child age, rather than uniformly applied across the 5–11 year age range.

Association of birthweight with diabetes, hypertension, and ischemic heart disease in young adulthood: a retrospective cohort study.

Birthweight has been associated with diabetes in a reverse J-shape (highest risk at low birthweight and moderately high risk at high birthweight) and inversely associated with hypertension in adulthood with inconsistent evidence for cardiovascular disease. There is a lack of population-based studies examining the incidence of cardiometabolic outcomes in young adults born with low and high birthweights. To evaluate the association between birthweight and diabetes, hypertension, and ischemic heart disease (IHD) in young adulthood, we conducted a retrospective cohort study of 874,904 singletons born in Ontario, Canada, from 1994 to 2002, identified from population-based health administrative data. Separate Cox regression models examined birthweight in association with diabetes, hypertension, and IHD adjusting for confounders. Among adults 18-26 years, the diabetes incidence rate was 18.15 per 100,000 person-years, hypertension was 15.80 per 100,000 person-years, and IHD was 1.85 per 100,000 person-years. Adjusted hazard ratios (AHR) for the hazard of diabetes with low (<2500g) and high (>4000g), compared with normal (2500-4000g) birthweight, were 1.46 (95% CI 1.28, 1.68) and 1.09 (0.99, 1.21), respectively. AHR for hypertension with low and high birthweight were 1.34 (1.15, 1.56) and 0.86 (0.77, 0.97), respectively. AHR for IHD with low and high birthweight were 1.28 (0.80, 2.05) and 0.97 (0.71, 1.33), respectively. Overall, birthweight was associated with diabetes in young adults in a reverse J-shape and inversely with hypertension. There was insufficient evidence of an association with IHD. Further evidence is needed to understand the causal mechanisms between birthweight and cardiometabolic diseases in young adults.

Population-Based Trends in Complexity of Hospital Inpatients

Clinical experience suggests that hospital inpatients have become more complex over time, but few studies have evaluated this impression. To assess whether there has been an increase in measures of hospital inpatient complexity over a 15-year period. This cohort study used population-based administrative health data from nonelective hospitalizations from April 1, 2002, to January 31, 2017, to describe trends in the complexity of inpatients in British Columbia, Canada. Hospitalizations were included for individuals 18 years and older and for which the most responsible diagnosis did not correspond to pregnancy, childbirth, the puerperal period, or the perinatal period. Data analysis was performed from July to November 2023. The passage of time (15-year study interval). Measures of complexity included patient characteristics at the time of admission (eg, advanced age, multimorbidity, polypharmacy, recent hospitalization), features of the index hospitalization (eg, admission via the emergency department, multiple acute medical problems, use of intensive care, prolonged length of stay, in-hospital adverse events, in-hospital death), and 30-day outcomes after hospital discharge (eg, unplanned readmission, all-cause mortality). Logistic regression was used to estimate the relative change in each measure of complexity over the entire 15-year study interval. The final study cohort included 3 367 463 nonelective acute care hospital admissions occurring among 1 272 444 unique individuals (median [IQR] age, 66 [48-79] years; 49.1% female and 50.8% male individuals). Relative to the beginning of the study interval, inpatients at the end of the study interval were more likely to have been admitted via the emergency department (odds ratio [OR], 2.74; 95% CI, 2.71-2.77), to have multimorbidity (OR, 1.50; 95% CI, 1.47-1.53) and polypharmacy (OR, 1.82; 95% CI, 1.78-1.85) at presentation, to receive treatment for 5 or more acute medical issues (OR, 2.06; 95% CI, 2.02-2.09), and to experience an in-hospital adverse event (OR, 1.20; 95% CI, 1.19-1.22). The likelihood of an intensive care unit stay and of in-hospital death declined over the study interval (OR, 0.96; 95% CI, 0.95-0.97, and OR, 0.81; 95% CI, 0.80-0.83, respectively), but the risks of unplanned readmission and death in the 30 days after discharge increased (OR, 1.14; 95% CI, 1.12-1.16, and OR, 1.28; 95% CI, 1.25-1.31, respectively). By most measures, hospital inpatients have become more complex over time. Health system planning should account for these trends.

Use of administrative claims data in observational studies of antirheumatic medication effects on pregnancy outcomes: a scoping review protocol.

The primary objective of this review is to examine which disease-modifying antirheumatic drugs (DMARDs) and biologics used to treat pregnant individuals with rheumatic conditions have been reported in observational studies using population-based health administrative data. The secondary objective is to describe which adverse pregnancy outcomes (both maternal and neonatal) have been reported, their definitions, and corresponding diagnostic and/or procedural codes. Pregnant individuals are typically excluded from drug trials due to unknown potential risks to both the pregnant person and fetus, leaving most antirheumatic drugs understudied for use in pregnancy. Despite these substantial knowledge gaps, most pregnant individuals continue to be maintained on antirheumatic medications due to the benefits generally outweighing the risks. In contrast to previous systematic reviews of findings from randomized trials, our scoping review aims to leverage this real-world data to generate real-world evidence of antirheumatic drug safety during pregnancy. Articles must report on observational studies using population-based health administrative data from pregnant individuals with rheumatic conditions (rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis, and psoriatic arthritis) receiving antirheumatic drug therapy (DMARDs and biologics). Randomized trials, reviews, case studies, opinion pieces, and abstracts will be excluded. Electronic databases (MEDLINE [Ovid], Embase [Ovid], CINAHL [EBSCOhost]) and gray literature (OpenGrey, Health Services Research Projects in Progress, World Health Organization Library, and Google Scholar) will be searched for relevant evidence. Search terms will combine 4 concepts: rheumatic diseases, drug therapy, pregnancy, and health care administrative data. Identified articles will be independently screened, selected, and extracted by 2 researchers. Data will be analyzed descriptively and presented in tables. Open Science Framework https://osf.io/5e6tp.

Real-World Cost-Consequence Analysis of an Integrated Chronic Disease Management Program in Saskatchewan, Canada.

An integrated disease management program otherwise called a clinical pathway was recently implemented in Saskatchewan, Canada for patients living with chronic obstructive pulmonary disease (COPD). This study compared the real-world costs and consequences of the COPD clinical pathway program with 2 control treatment programs. The study comprised adult COPD patients in Regina (clinical pathway group, N = 759) matched on propensity scores to 2 independent control groups of similar adults in (1) Regina (historical controls, N = 759) and (2) Saskatoon (contemporaneous controls, N = 759). The study measures included patient-level healthcare costs and acute COPD exacerbation outcomes, both tracked in population-based administrative health data over a one-year follow-up period. Analyses included Cox proportional hazards models and differences in means between groups. The bias-corrected and accelerated bootstrap method was used to calculate 95% confidence intervals (CI). The COPD pathway patients had lower risks of moderate (hazard ratio [HR] =0.57, 95% CI [0.40-0.83]) and severe (HR = 0.43, 95% CI [0.28-0.66]) exacerbations compared to the historical control group, but similar risks compared with the contemporaneous control group. The COPD pathway patients experienced fewer episodes of exacerbations compared with the historical control group (mean difference = -0.30, 95% CI [-0.40, -0.20]) and the contemporaneous control group (mean difference = -0.12, 95% CI [-0.20, -0.03]). Average annual healthcare costs in Canadian dollars were marginally higher among patients in the COPD clinical pathway (mean = $10 549, standard deviation [SD] =$18 149) than those in the contemporaneous control group ($8841, SD = $17 120), but comparable to the historical control group ($10 677, SD = $21 201). The COPD pathway provides better outcomes at about the same costs when compared to the historical controls, but only slightly better outcomes and at a marginally higher cost when compared to the contemporaneous controls.

THE IMPACT OF COVID-19 ON RESIDENTS AND FAMILY/FRIEND CAREGIVERS IN ASSISTED LIVING HOMES

Abstract Healthcare reforms have neglected assisted living (AL) and nursing homes (NHs) for decades, setting them up for the excessive rates of death and suffering during COVID-19. Research before and during the pandemic has primarily focused on NHs, largely overlooking AL. AL is rapidly expanding, caring for people with similar vulnerabilities as those in NHs, yet is less regulated, offers fewer services, has lower staffing/skill mix levels and requires significant family/friend involvement in care. This symposium presents a program of research (COVCARES, COVID-19 and the Care of Assisted living Residents), aiming to understand how the pandemic has impacted AL resident, family/friend, and facility outcomes, and how resident outcomes compare between NHs and AL. Our research started over a decade ago with the first population-based cohort study comparing AL and NHs in Canada. Our current research includes repeated surveys (10/2020–04/2021 and 07/2021–09/2021) with family/friend caregivers and AL facilities, and population-based clinical and health administrative data (2017-2021) from AL and NH residents in Western Canada. Five presentations will report on the design/methods/goals of COVCARES (#1), the impact of the pandemic on family/friend involvement in AL resident care (#2), impacted of the pandemic on psychotropic drug prescriptions in AL (#3), and the association of AL home preparedness for and response to the pandemic on resident pain (#4) and loneliness (#5). Our discussant (Anna Beeber) will highlight similarities and differences between AL and NHs, similarities and differences in both settings between the US and Canada, and how policymakers can account for these differences.

COVID-19 AND THE CARE OF ASSISTED LIVING RESIDENTS: THE COVCARES PROGRAM OF RESEARCH

Abstract This presentation describes the goals, design and methods of the COVID-19 and the Care of Assisted living Residents (COVCARES) program of research. Our goals were to address critical knowledge gaps related to how COVID-19 impacted assisted living (AL) residents, family/friend caregivers, and homes, and to compare how outcomes differed between AL and nursing homes (NH). Partnering closely with provincial Alzheimer Societies, family caregiver advocates, and health policy decision makers, we conducted two interconnected studies: The first was a prospective cohort study, surveying family/friend caregivers of AL residents and directors of care of AL homes in the Canadian provinces of Alberta and British Columbia twice (10/2020–04/2021 and 07/2021–09/2021). 673 caregivers and 104 AL homes responded to our first survey. Of those, 386 caregivers and 78 AL homes submitted a second survey. The second was a population-based retrospective cohort study (01/2017–12/2021), using clinical and health administrative data of all AL and NH residents in Alberta. Data included Resident Assessment Instrument (RAI) records, acute care and emergency department admission data, prescription medications, data on COVID-19 infections, and vital statistics of 23,355 AL residents and 41,583 NH residents. Analyzing each of the aforementioned data sets individually, and linking family and facility surveys, as well as resident and facility survey data, we provide unique insights into the impacts of the COVID-19 pandemic on AL settings. The presentations in this symposium will share selected key findings from our program of research.

Impact of non-medical cannabis legalization with market restrictions on health service use and incident cases of psychotic disorder in Ontario, Canada

BackgroundCannabis is a risk factor in the onset and persistence of psychotic disorders. There is concern that non-medical cannabis legalization in Canada may have population-level impacts on psychotic disorders. We sought to examine changes in health service use and incident cases of psychotic disorder following cannabis legalization, during a period of tight restrictions on retail stores and product types. MethodsWe conducted a cross-sectional interrupted time-series analysis using linked population-based health administrative data from Ontario (Canada) from January 2014 to March 2020. We identified psychosis-related outpatient visits, emergency department visits, hospitalizations, and inpatient length of stay, as well as incident cases of psychotic disorders, among people aged 14 to 60 years. ResultsWe did not find evidence of increases in health service use or incident cases of psychotic disorders over the short-term (17 month) period following cannabis legalization. However, we found clear increasing trends in health service use and incident cases of substance-induced psychotic disorders over the entire observation window (2014–2020). ConclusionOur findings suggest that the initial period of tight market restriction following legalization of non-medical cannabis was not associated with an increase in health service use or frequency of psychotic disorders. A longer post-legalization observation period, which includes expansion of the commercial cannabis market, is needed to fully understand the population-level impacts of non-medical cannabis legalization; thus, it would be premature to conclude that the legalization of non-medical cannabis did not lead to increases in health service use and incident cases of psychotic disorder.

What are effective vaccine distribution approaches for equity-deserving and high-risk populations during COVID-19? Exploring best practices and recommendations in Canada: protocol for a mixed-methods multiple case codesign study

IntroductionThe WHO has stated that vaccine hesitancy is a serious threat to overcoming COVID-19. Vaccine hesitancy among underserved and at-risk communities is an ongoing challenge in Canada. Public confidence in...

Cancer risk, disease-modifying therapy, and age in multiple sclerosis: A retrospective population-based cohort study

BackgroundLong-term population-based safety studies are needed to investigate cancer outcomes in people with multiple sclerosis (MS) treated with modern disease-modifying therapy (DMT). ObjectivesTo investigate if exposure to DMT increases the risk of invasive cancer in MS. MethodsWe used population-based administrative health data from Alberta, Canada between 2008 and 2018. DMT exposure was defined in two ways: first as exposure to any DMT, and second by DMT type (modulating, sequestering, depleting). Study outcome was time to first diagnosis of invasive cancer. Cancer risk was compared to the general population using standardized incidence ratios (SIRs) and to the unexposed MS cases using hazard ratios (HRs). ResultsThe analysis included 14,313 MS cases: 5,801 (40.5 %) were exposed to DMT. Median (interquartile range) follow-up was 8.4 (4.3, 10.4) years. Compared to the general population, there was no difference in cancer risk for the overall MS population (SIR: 0.94, 95 % confidence interval [CI]: 0.87, 1.02) or the DMT-exposed MS cases (SIR: 0.89; 95 % CI: 0.75, 1.05). Compared to unexposed MS cases, we found an interaction with age for exposure to any DMT (p = 0.001) and modulating DMT (p = 0.001), indicating that a difference in the risk of cancer associated with DMT depends on age. Cancer risk was not associated with exposure to sequestering DMT (HR: 1.28, 95 % CI: 0.78, 2.08) or depleting DMT (HR: 2.29, 95 % CI: 0.86, 6.14). ConclusionsCancer risk for MS patients was similar to the general population. In the MS population, the age-dependent effect of DMT for cancer risk suggests a higher risk of cancer with age 62 or older and a protective effect at younger age. Further investigation is required to clarify whether the interaction between DMT exposure and age is a causal effect.

Evaluating the Association between the Implementation of the PoET Southwest Spread Project and Reductions in Acute Care Transfers from Long-Term Care: A Quasi-Experimental Matched Cohort Study Using Population-Level Health Administrative Data

ObjectivesTo measure changes in resident-level acute care transfer rates after the PoET Southwest Spread Project (PSSP), and to identify patient and long-term care (LTC) home characteristics associated with acute care transfers after program launch. DesignQuasi-experimental matched (1:1 ratio) cohort study design using linked population-based health administrative data. SettingSixty publicly funded LTC homes (PSSP = 30; control = 30) in Ontario, Canada, from November 2019 to December 2021. MethodsWe matched 30 PSSP homes to 30 control homes with similar characteristics and described incidence rates for resident-level acute care transfers during the 7-month post-implementation period. We used generalized linear mixed models to evaluate the association between PSSP implementation and acute care transfers during the post-implementation period. We adjusted resident-level characteristics (ie, age, sex, comorbidity status) and home-level characteristics (ie, rurality status, profit model, COVID-19 impact). We identified a decedent sub-cohort to measure transfer patterns during the last 2 months of life. ResultsA matched cohort of 8894 residents (PSSP = 4103; control = 4791) was captured. Incidence rates of transfers increased during the post-implementation period for both PSSP (78.8 to 80.9 transfers per 1000 person-months) and control residents (66.9 to 67.9 transfers per 1000 person-months). After adjusting for covariates of interest, PSSP exposure was associated with a reduction in acute care transfers during the post-implementation period after adjusting for covariates (incidence rate ratio, 0.73; 95% CI, 0.62–0.87; P = .0002). Older age and select health regions were associated with reduced transfers, whereas higher comorbidity status and higher COVID-19 outbreak days were associated with increases. Similar patterns persisted for transfers during the last 2 months of life. Conclusions and ImplicationsThis study systematically evaluated the impact of an ethics-based health care intervention in LTC using health care utilization databases. PoET implementation is associated with reduced acute care transfer rates, especially in the last 2 months of life in LTC.