Neighbourhood Income Quintile Research Articles

Examining The Care Pathways Patients Experience When Accessing Outpatient Psychiatric Care in British Columbia

The British Columbia (BC) mental health roadmap prioritizes equitable access to care. This study investigates the equity of care pathways experienced by BC residents accessing outpatient psychiatric care for the first time. Community-based care pathways are paramount as they indicate timely access to care and are less expensive for the health system. We analyzed linked administrative BC health data spanning April 1st 2013, to March 31st 2022, to study how sociodemographic factors relate to accessing psychiatric care pathways. Pathways to outpatient psychiatric care include a community-based pathway, hospitalization to primary care to outpatient psychiatry, and hospitalization directly to outpatient psychiatry. Sociodemographic factors considered were administrative sex, immigration recency and status, neighbourhood income quintile and being a recipient of a low-income drug plan. These relationships were analyzed using multinomial logistic regression, adjusting for age, location, fiscal year, and stratifying by mental disorder diagnoses. Being male, a low-income drug plan recipient, living in a lower income neighbourhood, or being a recent economic immigrant or permit holder was associated with increased odds of accessing outpatient psychiatric care via either hospitalization pathway. Having a diagnosis of schizophrenia/bipolar disorder was independently associated with both hospitalization pathways, and this diagnosis exacerbated the magnitude of the estimates for the sociodemographic characteristics. We find clear disparities in pathways to accessing outpatient psychiatric care. These disparities indicate health system failures in addressing specific population needs, highlighting the importance of targeted interventions, such as increasing the number of community health workers, to achieve equitable mental health care in BC.

Linking Community-based Substance Use Disorder Treatment to Health Administrative Data: understanding vulnerable populations.

IntroductionMost substance use disorder (SUD) treatment occurs in community settings. Community-based SUD treatment information is rarely captured or utilized. The objective of this study was to examine the efficiency of a data linkage of community-based SUD treatment to health administrative data holdings in Ontario, Canada, and to describe sociodemographic and clinical characteristics of individuals accessing SUD services. MethodsData from community-based SUD service providers (>180) from April 2015 to March 2022 were linked to administrative data holdings at ICES. Linkage rates were evaluated. Sociodemographic (age, sex, neighbourhood-level income) and clinical (substance use, physician visits, Emergency Department (ED) visits and hospitalizations) characteristics were evaluated. ResultsThe linkage rate of DATIS ICES data holdings was >92% for all years (2015-2022). Of the 234,501 individuals admitted to a DATIS program, 36.1% were female, 46.2% were 25-44 years old, and 51.6% resided in the two lowest neighbourhood income quintiles. Alcohol (33.4%) was the most common substance identified. For outpatient care occurring within 1 year prior to admission, around 56.0% and 23.3% had Mental Health and Addictions (MHA) related primary care and psychiatrist visits, respectively. For acute health services, 29.8% and 14.2% had a MHA- related ED visit or hospitalization, respectively. DiscussionSUD treatment data from community settings can be successfully linked to other health administrative data. Individuals with SUD have a high rate of acute health care use, and a relatively low access to psychiatrists. SUD treatment data linkage should be used to understand how to optimize access to care for vulnerable individuals.

Exploring variations in patient safety events across equity-deserving populations

The objective of this analysis was to examine variations in rates of hospital harm (HH), an important indicator of patient safety events, across population subgroups in Canada. We conducted a descriptive study of HH in provinces and territories using three years (2016 to 2018) of CIHI’s Discharge Abstract Database (DAD) linked to the 2016 Canadian Census, also known as Statistics Canada’s Canadian Census Health and Environment Cohorts (CanCHEC). We investigated the influence of sociodemographic variables not generally available in hospital administrative data. We calculated age-standardized rates (ASR) per 100 hospital discharges and 95% confidence intervals for HH, stratified by sex, income (area and individual), racialized group, education, immigration status, language, disability status, social and material deprivation, and geography (urban vs. rural/remote). Despite males experiencing higher rates of harm (ASR 4.36 vs. 4.23), overall females experienced 54% of all HH events, with an average age of 64 (vs age 49 for those discharged without a HH event). For neighbourhood income quintile, the highest rates of HH were observed in the lowest quintile (4.08, 4.04 – 4.11). The rate of HH decreased as neighbourhood income increased. Patients from rural/remote neighbourhoods had lower rates of HH (3.7, 3.66-3.73) than those living in urban neighbourhoods (4.47, 4.44-4.49). Additional equity-stratified results will be presented. Our analysis revealed that marginalized populations were more likely to experience a harmful event during their hospital stay. Measuring and monitoring inequalities in patient safety provides health systems with information to better understand, target, and evaluate healthcare quality improvement initiatives.

Brief Report: A population-based study of the impact of the COVID-19 pandemic on benzodiazepine use among children and young adults.

The COVID-19 pandemic was associated with increases in the prevalence of depression and anxiety among children and young adults. We studied whether the pandemic was associated with changes in prescription benzodiazepine use. We conducted a population-based study of benzodiazepine dispensing to children and young adults ≤ 24 years old between January 1, 2013, and June 30, 2022. We used structural break analyses to identify the pandemic month(s) when changes in prescription benzodiazepine dispensing occurred, and interrupted time series models to quantify changes in dispensing following the structural break and compare observed and expected benzodiazepine use. A structural break occurs where there is a sudden change in the trend of a time series. We observed an immediate decline in benzodiazepine dispensing of 23.6 per 100,000 (95% confidence interval [CI]: -33.6 to -21.2) associated with a structural break in April 2020, followed by a monthly decrease in the trend of 0.3 per 100,000 (95% CI: -0.74 to 0.14). Lower than expected benzodiazepine dispensing rates were observed each month of the pandemic from April 2020 onward, with relative percent differences ranging from - 7.4% (95% CI: -10.1% to - 4.7%) to -20.9% (95% CI: -23.2% to -18.6%). Results were generally similar in analyses stratified by sex, age, neighbourhood income quintile, and urban versus rural residence. Further research is required to understand the clinical implications of these findings and whether these trends were sustained with further follow-up.

Income differences in time to colon cancer diagnosis.

People with low income have worse outcomes throughout the cancer care continuum; however, little is known about income and the diagnostic interval. We described diagnostic pathways by neighborhood income and investigated the association between income and the diagnostic interval. This was a retrospective cohort study of colon cancer patients diagnosed 2007-2019 in Ontario using routinely collected data. The diagnostic interval was defined as the number of days from the first colon cancer encounter to diagnosis. Asymptomatic pathways were defined as first encounter with a colonoscopy or guaiac fecal occult blood test not occurring in the emergency department and were examined separately from symptomatic pathways. Quantile regression was used to determine the association between neighborhood income quintile and the conditional 50th and 90th percentile diagnostic interval controlling for age, sex, rural residence, and year of diagnosis. A total of 64,303 colon cancer patients were included. Patients residing in the lowest income neighborhoods were more likely to be diagnosed through symptomatic pathways and in the emergency department. Living in low-income neighborhoods was associated with longer 50th and 90th-percentile symptomatic diagnostic intervals compared to patients living in the highest income neighborhoods. For example, the 90th percentile diagnostic interval was 15 days (95% CI 6-23) longer in patients living in the lowest income neighborhoods compared to the highest. These findings reveal income inequities during the diagnostic phase of colon cancer. Future work should determine pathways to reducing inequalities along the diagnostic interval and evaluate screening and diagnostic assessment programs from an equity perspective.

High Healthcare Costs in Childhood Inflammatory Bowel Disease: Development of a Prediction Model Using Linked Clinical and Health Administrative Data.

The incidence of pediatric-onset inflammatory bowel disease (IBD) and the costs of caring for individuals with IBD are both increasing. We calculated the direct healthcare costs of pediatric IBD in the first year after diagnosis and developed a model to predict children who would have high costs (top 25th percentile). Using data from the Canadian Children IBD Network inception cohort (≤16 years of age, diagnosed between 2013 and 2019) deterministically linked to health administrative data from Ontario, Canada, we estimated direct healthcare and medication costs accrued between 31 and 365 days after diagnosis. Candidate predictors included age at diagnosis, sex, rural/urban residence location, distance to pediatric center, neighborhood income quintile, IBD type, initial therapy, disease activity, diagnostic delay, health services utilization or surgery around diagnosis, regular primary care provider, and receipt of mental health care. Logistic regression with stepwise elimination was used for model building; 5-fold nested cross-validation optimized and improved model accuracy while limiting overfitting. The mean cost among 487 children with IBD was CA$15 168±15 305. Initial treatment (anti-tumor necrosis factor therapy, aminosalicylates, or systemic steroids), having a mental health care encounter, undergoing surgery, emergency department visit at diagnosis, sex, and age were predictors of increased costs, while having a regular primary care provider was a predictor of decreased costs. The C-statistic for our model was 0.71. The cost of caring for children with IBD in the first year after diagnosis is immense and can be predicted based on characteristics at diagnosis. Efforts that mitigate rising costs without compromising quality of care are needed.

Geographic clustering of cannabis stores in Canadian cities: A spatial analysis of the legal cannabis market 4 years post-legalisation.

Following the legalisation of non-medical cannabis in 2018, the number of cannabis stores in Canada has rapidly expanded with limited regulation on their geographic placement. This study characterised the clustering of cannabis stores in Canadian cities and evaluated the association of clustering with provincial policy and sociodemographic variables. Cross-sectional spatial analysis of cannabis store density in dissemination areas ('neighbourhoods', n = 39,226) in Canadian cities in September 2022. Cannabis store density was defined as the count of stores within 1000 m of a neighbourhood centre. Clusters of high-density cannabis retail were identified using Local Indicators of Spatial Autocorrelation. Associations between provincial policy (privatised vs. public market), sociodemographic variables and cannabis store density were evaluated using multivariable regression. Clusters of high-density cannabis retail were identified in 86% of Canadian cities, and neighbourhoods in clusters had a median of 5 stores within 1000 m. Toronto, Canada's most populous city, had the most extreme clustering where neighbourhoods in clusters had a median of 10 stores (and a maximum of 25 stores) within 1000 m. Neighbourhoods in private versus public retail markets had a significantly higher neighbourhood-level density of cannabis stores (adjusted rate ratio [aRR] 63.37, 95% confidence interval [CI] 25.66-156.33). Lower neighbourhood income quintile was also associated with a higher neighbourhood-level density of cannabis stores (Q5 vs. Q1, aRR 1.28, 95% CI 1.17-1.40). Since cannabis was legalised, clusters of high-density cannabis retail have emerged in most Canadian cities and were more likely to form lower income neighbourhoods and in private retail markets.

A population-based analysis of the management of symptoms of depression among patients with stage IV non-small cell lung cancer (NSCLC) in Ontario, Canada.

Patients with lung cancer can experience significant psychological morbidities including depression. We characterize patterns and factors associated with interventions for symptoms of depression in stage IV non-small cell lung cancer (NSCLC). We conducted a population-based cohort study using health services administrative data in Ontario, Canada of stage IV NSCLC diagnosed from January 2007 to September 2018. A positive symptom of depression score was defined by reporting at least one ESAS (Edmonton Symptom Assessment System) depression score ≥ 2 following diagnosis until the end of follow-up (September 2019). Patient factors included age, sex, comorbidity burden, rurality of residence, and neighbourhood income quintile. Interventions included psychiatry assessment, psychology referral, social work referral and anti-depressant medical therapy (for patients ≥ 65years with universal drug coverage). Multivariable modified Poisson regression models were used to examine the association between patient factors and intervention use for patients who reported symptoms of depression. In the cohort of 13,159 patients with stage IV NSCLC lung cancer, symptoms of depression were prevalent (71.4%, n = 9,397). Patients who reported symptoms of depression were more likely to receive psychiatry assessment/psychology referral (7.8% vs 3.5%; SD [standardized difference] 0.19), social work referral (17.4% vs 11.9%; SD 0.16) and anti-depressant prescriptions (23.8% vs 13.8%; SD 0.26) when compared to patients who did not report symptoms of depression respectively. In multivariable analyses, older patients were less likely to receive any intervention. Females were more likely to obtain a psychiatry assessment/psychology referral or social work referral. In addition, patients from non-major urban or rural residences were less likely to receive psychiatry assessment/psychology referral or social work referral, however patients from rural residences were more likely to be prescribed anti-depressants. There is high prevalence of symptoms of depression in stage IV NSCLC. We identify patient populations, including older patients and rural patients, who are less likely to receive interventions that will help identifying and screening for symptoms of depression.

Understanding the Influence of Single Payer Health Insurance on Socioeconomic Disparities in Total Hip Arthroplasty (THA) Utilization: A Transnational Analysis.

Access to care varies between countries. It is theorized that income-based disparities in access may be reduced in countries with universal health insurance relative to the United States, but data are currently limited. We hypothesized that income-based differences in total hip arthroplasty (THA) utilization and outcomes would be larger in the United States than in Canada. We retrospectively compared all patients undergoing THA from 2012 to 2018 in Pennsylvania, the United States, and Ontario, Canada. We compared age-standardized and sex-standardized per-capita THA utilization in the United States and Canada overall and across different income strata, where income strata were defined by neighborhood income quintile. We also examined income-based differences in rates of 1-year revision, 90-day mortality, and 90-day readmission. Overall THA utilization per 10,000 people per year was higher across all income groups in Pennsylvania compared with Ontario (15.1 versus 8.8, P < 0.001 in lowest-income quintile; 21.4 versus 12.6, P < 0.001 in highest-income quintile). Income-based differences in utilization in the highest-income vs lowest-income quintile groups were greater in Ontario (43.2%) than Pennsylvania (41.7%). The adjusted odds for the lowest-income group compared with the highest-income group of 1-year revision were greater in Ontario compared with Pennsylvania (P = 0.03), and risk of 90-day mortality and 90-day readmission was similar between the regions. Income-based differences in THA utilization were more notable in Ontario than in Pennsylvania. In addition, patients in low-income communities in Ontario were at equal or greater risk relative to high-income community patients for adverse outcomes compared with patients in Pennsylvania. Income-based disparities in THA utilization and outcomes were smaller in the United States than in Canada, in contrast to what might be expected. III.

Sex Differences in Complications Following Total Hip Arthroplasty: A Population-Based Study

BackgroundThe relationship between sex and outcomes, especially complications, after total hip arthroplasty (THA) has not been well established. This study aimed to identify if patient biological sex significantly impacted complications after THA in Ontario, Canada. MethodsA population-based retrospective cohort study of patients undergoing primary THA in Ontario from April 1, 2015 to March 31, 2020 was conducted. The primary outcome was major surgical complications within a year postsurgery (a composite of revision, deep infection requiring surgery, and dislocation). Secondary outcomes included the individual component of the composite primary outcome and major medical complications within 30 days. Proportional hazards regression calculated the adjusted hazards ratio for major surgical complications in men relative to women, adjusting for age, comorbidities, neighborhood income quintile, surgeon and hospital volume, and year of surgery. ResultsA total of 67,077 patients (median age 68 years; 54.1% women) from 61 hospitals were included; women were older with a higher prevalence of frailty. Women had a higher rate of major surgical complications within 1 year of surgery compared to men (2.9 versus 2.5%, adjusted odds ratio 1.19, 95% confidence interval 1.08 to 1.33, P = .0009). Conversely, men had a higher risk for medical complications within 30 days (6.3 versus 2.7%, P < .001). ConclusionsObservable sex disparities exist in post-THA complications; women face surgical complications predominantly, while medical complications are more prevalent in men. These insights can shape preoperative patient consultations. Level of EvidenceLevel III.

Health Services Utilization and Specialist Care in Pediatric Inflammatory Bowel Disease: A Multiprovince Population-Based Cohort Study.

Patterns of health services utilization among children with inflammatory bowel disease (IBD) are important to understand as the number of children with IBD continues to increase. We compared health services utilization and surgery among children diagnosed <10 years of age (Paris classification: A1a) and between 10 and <16 years of age (A1b). Incident cases of IBD diagnosed <16 years of age were identified using validated algorithms from deterministically linked health administrative data in 5 Canadian provinces (Alberta, Manitoba, Nova Scotia, Ontario, Quebec) to conduct a retrospective cohort study. We compared the frequency of IBD-specific outpatient visits, emergency department visits, and hospitalizations across age groups (A1a vs A1b [reference]) using negative binomial regression. The risk of surgery was compared across age groups using Cox proportional hazards models. Models were adjusted for sex, rural/urban residence location, and mean neighborhood income quintile. Province-specific estimates were pooled using random-effects meta-analysis. Among the 1165 (65.7% Crohn's) children with IBD included in our study, there were no age differences in the frequency of hospitalizations (rate ratio [RR], 0.88; 95% confidence interval [CI], 0.74-1.06) or outpatient visits (RR, 0.95; 95% CI, 0.78-1.16). A1a children had fewer emergency department visits (RR, 0.70; 95% CI, 0.50-0.97) and were less likely to require a Crohn's-related surgery (hazard ratio, 0.49; 95% CI, 0.26-0.92). The risk of colectomy was similar among children with ulcerative colitis in both age groups (hazard ratio, 0.71; 95% CI, 0.49-1.01). Patterns of health services utilization are generally similar when comparing children diagnosed across age groups.

Pregnancy Outcomes in Living Kidney Donors: Protocol of a Population-Based Cohort Study in Three Canadian Provinces.

A substantial proportion of living kidney donors are women of childbearing age. Some prior studies report a higher risk of gestational hypertension and pre-eclampsia in living kidney donors compared with nondonors. Further research is needed to better quantify the risk of adverse maternal, fetal/infant, and neonatal outcomes attributable to living kidney donation. To determine the risk of hypertensive disorders of pregnancy, including gestational hypertension, pre-eclampsia, and eclampsia, and other maternal and fetal/infant outcomes in living kidney donors compared with a matched group of nondonors of similar baseline health. Protocol for a population-based, matched cohort study using Canadian administrative health care databases. The protocol will be run separately in 3 provinces, Ontario, Alberta, and British Columbia, and results will be combined statistically using meta-analysis. The cohort will include women aged 18 to 48 years who donated a kidney between July 1992 and March 2022 and had at least one postdonation singleton pregnancy of ≥20 weeks gestation between January 1993 and February 2023. We expect to include at least 150 living kidney donors with over 200 postdonation pregnancies from Ontario and a similar number of donors and pregnancies across Alberta and British Columbia combined. Nondonors will include women from the general population with at least one pregnancy of ≥20 weeks gestation between January 1993 and February 2023. Nondonors will be randomly assigned cohort entry dates based on the distribution of nephrectomy dates in donors. The sample of nondonors will be restricted to those aged 18 to 48 years on their cohort entry dates with delivery dates at least 6 months after their assigned entry dates. A concern with donor and nondonor comparisons is that donors are healthier than the general population. To reduce this concern, we will also apply 30+ exclusion criteria to further restrict the nondonor group so that they have similar health measures at cohort entry as the donors. Donor and nondonor pregnancies will then be matched (1:4) on 5 potential confounders: delivery date, maternal age at delivery date, time between cohort entry and delivery date, neighborhood income quintile, and parity at delivery date. The primary outcome will be a composite of maternal gestational hypertension, preeclampsia, or eclampsia. Secondary maternal outcomes will include components of the primary outcome, early pre-eclampsia, severe maternal morbidity, cesarean section, postpartum hemorrhage, and gestational diabetes. Fetal/infant/neonatal outcomes will include premature birth/low birth weight, small for gestational age, neonatal intensive care unit admission, stillbirth, and neonatal death. The primary unit of analysis will be the pregnancy. We will compute the risk ratio of the primary composite outcome in donors versus nondonors using a log-binomial mixed regression model with random effects to account for the correlation within women with multiple pregnancies and within matched sets of donors and nondonors. We will perform the statistical analyses within each province and then combine aggregated results using meta-analytic techniques to produce overall estimates of the study outcomes. Due to regulations that prevent individual-level records from being sent to other provinces, we cannot pool individual-level data from all 3 provinces. Compared to prior studies, this study will better estimate the donation-attributable risk of adverse maternal, fetal/infant, and neonatal outcomes. Transplant centers can use the results to counsel female living donor candidates of childbearing age and to inform recommended practices for the follow-up and care of living kidney donors who become pregnant.

Social Determinants of Health in Pediatric Ophthalmology Patients: Availability of Data in the Electronic Health Record and Association With Clinic Attendance.

To characterize the availability of social determinants of health data in the electronic health record of pediatric ophthalmology patients and to examine the association of social determinants of health with attendance at scheduled operating room and clinic visits. This was a retrospective cohort study of pediatric ophthalmology patients seen at The Hospital for Sick Children between June 1, 2018, and May 23, 2022. Data were collected on demographics, diagnosis, and management-plan. The χ2 tests and multivariable regression were used to examine associations between social determinants of health and attendance at scheduled operating room and clinic visits. The cohort consisted of 26,102 study subjects with 31,288 unique eye-related diagnoses representing 57 unique ICD-10 codes. Availability of data in the electronic health record ranged from 100% for sex, age and postal code to 0.1% for ethnic group. Female sex (P = 0.004) and urbanicity (P = 0.05) were associated with higher operating room visit cancellations. Female sex (P = 0.002), age group 0-13 (P ≤ 0.001), low-medium neighborhood income quintile (P ≤ 0.001), residence of Northern Ontario (P ≤ 0.001), and urbanicity (P ≤ 0.001) were associated with higher clinic visit cancellations and no-shows. At a major tertiary-care hospital in Canada, key social determinant data such as ethnicity are not consistently available in the electronic health record of pediatric ophthalmology patients. Female sex, younger age, and living in a rural area or neighborhood with low-medium income quintile may be predictors of missed visits and require further study. This study highlights a need for improved documentation of social determinants of health variables in electronic health records.

Trends of Obesity over Time and Its Prognostic Significance in Children and Adolescents with Newly-Diagnosed Acute Lymphoblastic Leukemia in Canada: A Population-Based Study

Introduction Childhood obesity can result in a variety of adverse health outcomes and it has been associated with inferior survival in children and adolescents with acute lymphoblastic leukemia (ALL). With the rising incidence of childhood obesity in Canada, we seek to assess the prevalence of obesity and its prognostic significance in children and adolescents with newly-diagnosed ALL in Canada. Methods We conducted a retrospective cohort study using the Cancer in Young People in Canada (CYP-C) database, a national population-based pediatric surveillance program collecting in-depth clinical data from all cancer patients &amp;lt;15 years old before 2015 and &amp;lt;19 years old after 2015 in Canada. This study included patients aged 2 to 18 years old with newly-diagnosed ALL and treated at one of the 17 pediatric oncology centers across Canada from January 1, 2001 to December 31, 2020. Obese patients were defined as patients with a body mass index (BMI) at or greater than the 95 th age and sex-adjusted percentile as per the Centers for Disease Control &amp; Prevention (CDC). Patients &amp;lt;2 years old were excluded given no BMI data could be derived from CDC growth charts. The main outcomes were event-free survival (EFS) and overall survival (OS). EFS was defined as time from ALL diagnosis to first event (relapse or death). OS was defined as time from ALL diagnosis to death from any cause. Patients without an event were censored at date of last contact. Predictors of obesity were explored using logistic regression. Univariate and multivariable Cox proportional hazards models were used to compare EFS and OS between patients with and without obesity. Results A total of 3458 ALL patients were included. The median BMI was 16.4 kg/m 2 (interquartile range (IQR): 15.2-18.1 kg/m 2). Eleven percent of children were obese at the time of ALL diagnosis. The prevalence of obesity significantly increased over time compared to that at ALL diagnosis: 18.9% at 1 year (p&amp;lt;0.0001), 25.8% at 2 years (p&amp;lt;0.0001), 23.3% at 3 years (p&amp;lt;0.0001), 21.8 % at 4 years (p&amp;lt;0.0001) and 20% at 5 years (p&amp;lt;0.0001). The prevalence of obesity did not vary according to age at diagnosis, gender, neighborhood income quintile (NIQ), ALL immunophenotype and treatment era ( Table 1). Non-Caucasian race (odds ratio (OR): 1.35 [95% confidence interval (CI) 1.09 -1.67]; p=0.005), presenting white blood cell (WBC) ≥ 50 x 10 9/L (OR: 1.38 [1.07 - 1.77]; p=0.01) and central nervous disease (CNS) disease (OR: 1.44 [1.10 - 1.88]; p=0.009) were significantly associated with increased risk of obesity at diagnosis. The 5-year EFS of obese patients at ALL diagnosis were significantly inferior to those of non-obese patients (85.3% vs. 90.6%; p=0.0008) ( Figure 1). The 5-year OS was 90.4% for obese vs. 94.9% for non-obese patients at diagnosis (p=0.003). The causes of death in the entire cohort were 1) related to disease (73.5%); 2) related to treatment toxicities (15.6%); and 3) due to other causes (10.9%). In univariate analysis, obese patients at ALL diagnosis had a higher risk for worse EFS (Hazard Ratio (HR) 1.76, 95% CI 1.34 - 2.32, p&amp;lt;0.0001)and OS (HR 1.99, 95% CI 1.41- 2.81, p&amp;lt;0.0001) compared to non-obese patients. In addition, age ≥ 10 years old at diagnosis, CNS disease, presenting WBC count ≥ 50x10 9/L, non-favorable cytogenetics and treatment era before 2010 were also significantly associated with worse EFS and OS in univariate analyses. In multivariable models controlling for patients' age at diagnosis, gender, presenting WBC, CNS status, NIQ, ethnicity, treatment era and ALL immunophenotype, obesity at ALL diagnosis retained independent significance with a HR of 1.67, 95% CI 1.26-2.21, p=0.0004 for EFS and a HR of 1.83, 95% CI 1.29-2.61, p=0.0008 for OS. Conclusion In this population-based study of children and adolescents with ALL in Canada, obesity was found in 11% of patients at ALL diagnosis, peaked at 2 years and remained significantly increased at 5 years from initial diagnosis. Patients with higher risk features such as WBC ≥ 50 x 10 9/L and CNS disease were more likely to be obese at diagnosis. Nevertheless, obesity at ALL diagnosis remained independently associated with inferior EFS and OS even after adjustment for these high-risk features. More mechanistic studies are needed to better understand the relationship between obesity and outcome to inform future trial designs.

Cancer Screening Disparities Before and After the COVID-19 Pandemic

Breast, cervical, and colorectal cancer-screening disparities existed prior to the COVID-19 pandemic, and it is unclear whether those have changed since the pandemic. To assess whether changes in screening from before the pandemic to after the pandemic varied for immigrants and for people with limited income. This population-based, cross-sectional study, using data from March 31, 2019, and March 31, 2022, included adults in Ontario, Canada, the country's most populous province, with more than 14 million people, almost 30% of whom are immigrants. At both dates, the screening-eligible population for each cancer type was assessed. Neighborhood income quintile, immigrant status, and primary care model type. For each cancer screening type, the main outcome was whether the screening-eligible population was up to date on screening (a binary outcome) on March 31, 2019, and March 31, 2022. Up to date on screening was defined as having had a mammogram in the previous 2 years, a Papanicolaou test in the previous 3 years, and a fecal test in the previous 2 years or a flexible sigmoidoscopy or colonoscopy in the previous 10 years. The overall cohort on March 31, 2019, included 1 666 943 women (100%) eligible for breast screening (mean [SD] age, 59.9 [5.1] years), 3 918 225 women (100%) eligible for cervical screening (mean [SD] age, 45.5 [13.2] years), and 3 886 345 people eligible for colorectal screening (51.4% female; mean [SD] age, 61.8 [6.4] years). The proportion of people up to date on screening in Ontario decreased for breast, cervical, and colorectal cancers, with the largest decrease for breast screening (from 61.1% before the pandemic to 51.7% [difference, -9.4 percentage points]) and the smallest decrease for colorectal screening (from 65.9% to 62.0% [difference, -3.9 percentage points]). Preexisting disparities in screening for people living in low-income neighborhoods and for immigrants widened for breast screening and colorectal screening. For breast screening, compared with income quintile 5 (highest), the β estimate for income quintile 1 (lowest) was -1.16 (95% CI, -1.56 to -0.77); for immigrant vs nonimmigrant, the β estimate was -1.51 (95% CI, -1.84 to -1.18). For colorectal screening, compared with income quintile 5, the β estimate for quntile 1 was -1.29 (95% CI, 16 -1.53 to -1.06); for immigrant vs nonimmigrant, the β estimate was -1.41 (95% CI, -1.61 to -1.21). The lowest screening rates both before and after the COVID-19 pandemic were for people who had no identifiable family physician (eg, moving from 11.3% in 2019 to 9.6% in 2022 up to date for breast cancer). In addition, patients of interprofessional, team-based primary care models had significantly smaller reductions in β estimates for breast (2.14 [95% CI, 1.79 to 2.49]), cervical (1.72 [95% CI, 1.46 to 1.98]), and colorectal (2.15 [95% CI, 1.95 to 2.36]) postpandemic screening and higher uptake of screening in general compared with patients of other primary care models. In this cross-sectional study in Ontario that included 2 time points, widening disparities before compared with after the COVID-19 pandemic were found for breast cancer and colorectal cancer screening based on income and immigrant status, but smaller declines in disparities were found among patients of interprofessional, team-based primary care models than among their counterparts. Policy makers should investigate the value of prioritizing and investing in improving access to team-based primary care for people who are immigrants and/or with limited income.

Trends in infection-related and infection-unrelated cancer incidence among people with and without HIV infection in Ontario, Canada, 1996-2020: a population-based matched cohort study using health administrative data.

People with HIV infection are at higher risk for certain cancers than the general population. We compared trends in infection-related and infection-unrelated cancers among people with and without HIV infection. We conducted a retrospective population-based matched cohort study of adults with and without HIV infection using linked health administrative databases in Ontario, Canada. Participants were matched on birth year, sex, census division (rurality), neighbourhood income quintile and region of birth. We followed participants from cohort entry until the earliest of date of cancer diagnosis, date of death, Nov. 1, 2020, or date of loss to follow-up. Incident cancers identified from Jan. 1, 1996, to Nov. 1, 2020, were categorized as infection-related or-unrelated. We examined calendar periods 1996-2003, 2004-2011 and 2012-2020, corresponding to the early combination antiretroviral therapy (cART), established cART and contemporary cART eras, respectively. We used competing risk analyses to examine trends in cumulative incidence by calendar period, age and sex, and cause-specific hazard ratios (HRs). We matched 20 304 people with HIV infection to 20 304 people without HIV infection. A total of 2437 cancers were diagnosed, 1534 (62.9%) among infected people and 903 (37.0%) among uninfected people. The risk of infection-related cancer by age 65 years for people with HIV infection decreased from 19.0% (95% confidence interval [CI] 15.6%-22.3%) in 1996-2011 to 10.0% (95% CI 7.9%-12.1%) in 2012-2020. Compared to uninfected people, those with HIV infection had similar HRs of infection-unrelated cancer but increased rates of infection-related cancer, particularly among younger age groups (25.1 [95% CI 13.2-47.4] v. 1.9 [95% CI 1.0-3.7] for age 18-39 yr v. ≥ 70 yr); these trends were consistent when examined by sex.Interpretation: We observed significantly higher rates of infection-related, but not infection-unrelated, cancer among people with HIV infection than among uninfected people. The elevated rate of infection-related cancer in 2012-2020 highlights the importance of early and sustained antiretroviral therapy along with cancer screening and prevention measures.

Postoperative buprenorphine continuation in stabilized buprenorphine patients: A population cohort study.

Sudden discontinuation of buprenorphine in the treatment of opioid use disorder can increase the risk of subsequent relapse and overdose. Little is known about buprenorphine use in the perioperative period. The aim of this study was to determine the rate of buprenorphine continuation after hospital discharge following surgery and factors associated with continuation. A population-based retrospective cohort study was conducted using administrative data from Ontario, Canada, between 2012 and 2018. The cohort included individuals on continuous buprenorphine prior to surgery. Logistic regression modeling was used to estimate the association of buprenorphine continuation with demographic, opioid agonist treatment, surgical and health service use factors. Administrative databases from Institute for Clinical Evaluative Sciences (ICES) were used, which capture the Ontario, Canada, population. The data sets describe physician billing, monitoring of controlled substances and hospital discharges. Adults (≥ 18 years, n = 2176) had received a buprenorphine/naloxone product continuously for at least 60 days for the treatment of opioid use disorder and subsequently underwent a surgical procedure. Continuation (versus discontinuation) of buprenorphine prescriptions in the 14 days after surgical discharge was recommended. Exposures included demographic, comorbidity, opioid agonist treatment, surgical and health service use characteristics. About 176 (8.1%) of the 2176 patients discontinued buprenorphine after surgery. Inpatient surgery (versus ambulatory) was associated with reduced odds of continuation, with an unadjusted odds ratio (OR) of 0.17 [95% confidence interval (CI) = 0.12-0.25] and an adjusted OR of 0.16 (95% CI = 0.11-0.23) after accounting for age, sex, rural residence, neighborhood income quintile, Charlson comorbidity index, psychiatric hospitalizations in the past 5 years and recent dispensed supply of buprenorphine (number needed to harm of 6.6). In Ontario, Canada, from 2012 to 2018, most patients receiving continuous preoperative buprenorphine therapy continued buprenorphine use after surgery. Inpatient surgery was a strong predictor of discontinuation compared with ambulatory procedures.

A214 WOMEN WITH INFLAMMATORY BOWEL DISEASE HAVE INCREASED HEALTH-CARE UTILIZATION DURING PREGNANCY AND POSTPARTUM COMPARED TO THOSE WITHOUT INFLAMMATORY BOWEL DISEASE: A POPULATION-BASED COHORT STUDY

Abstract Background Compared to those without inflammatory bowel disease (IBD), women with IBD may have increased health-care utilization during pregnancy and postpartum. This may lead to significant morbidity and decrease in quality of life. Characterizing this health-care use is important for health-policy purposes to determine methods to shift care to the ambulatory setting. Purpose We aimed to compare health-care utilization of women with and without IBD during preconception, pregnancy and postpartum. Method We accessed administrative databases and validated algorithms at the Institute of Clinical Evaluative Services (ICES) in Ontario to identify women (age 18-55) with and without IBD who had a completed live, singleton pregnancy between 2003 and 2018. The primary outcome was to characterize differences in emergency department (ED) visits and hospitalizations between women with and without IBD during the 12 months preconception, pregnancy, and in the 12 months postpartum. The secondary outcome was to assess differences in prenatal care between women with and without IBD. Multivariable negative binomial regression with generalizing estimating equations, accounting for multiple pregnancies for each patient, was performed to report incidence rate ratios (IRR) with 95% confidence intervals (95% CI). Covariates included maternal age at conception, location of residence at conception (rural vs. urban), socioeconomic status (using surrogate marker of neighborhood income quintile), and maternal comorbidity. Result(s) 9158 pregnancies in 6163 women with IBD and 1,729,411 pregnancies in 1,091,013 women without IBD were included. Women with IBD were older at time of delivery and had greater pre-pregnancy comorbidities. During pregnancy, women with IBD were more likely to visit the ED (IRR 1.13, 95% CI,1.08-1.18) and be hospitalized (IRR 1.11, 95% CI,1.01-1.21) for non-IBD specific reasons. Similarly, during postpartum, women with IBD were more likely to visit the ED (IRR 1.21, 95% CI, 1.15-1.27) and be hospitalized (IRR 1.18, 95% CI, 1.05-1.32) for non-IBD specific reasons. Venous thromboembolic events accounted for 7.0% of all postpartum hospitalizations in women with IBD compared to 2.7% in those without IBD (p&amp;lt;0.0001). There was no difference in ED visits and hospitalizations between women with and without IBD in preconception. Finally, women with IBD had greater number of prenatal visits with obstetricians during pregnancy and were more likely to receive a first trimester prenatal visit compared to those without IBD. Conclusion(s) Compared to those without IBD, women with IBD are more likely to visit the ED and be hospitalized during pregnancy and postpartum, particularly for venous thromboembolic events. Efforts should be made from a health policy perspective to increase access to ambulatory care for patients with IBD during the peripartum period which in turn may reduce acute setting health-services utilization. Please acknowledge all funding agencies by checking the applicable boxes below CCC Disclosure of Interest None Declared

A177 RISK OF VENOUS THROMBOEMBOLISM IN COVID-19 PATIENTS WITH INFLAMMATORY BOWEL DISEASE: A POPULATION-BASED MATCHED COHORT STUDY

Abstract Background Venous thromboembolism (VTE), is associated with significant morbidity and mortality. Inflammation increases the risk of VTE, and it is a well-recognised complication of both inflammatory bowel disease (IBD) and COVID-19. Purpose To compare the risk of VTE among individuals with and without IBD following a positive COVID-19 test. Method Using health administrative data from Ontario, Canada we conducted a retrospective matched cohort study.All Ontario residents with a positive SARS-CoV-2 PCR test between January 1,2020 and December 30,2021 who had been diagnosed with IBD prior to their COVID-19 infection (identified using a validated algorithm) were matched to 5 individuals without IBD based on year of birth, sex, mean neighbourhood income quintile, date of positive COVID-19 test, and rural/urban residence. Individuals with a cancer diagnosis in the 5 years prior to their first COVID-19 positive test were excluded. Individuals were followed from positive COVID-19 PCR test until VTE event, death, migration out of Ontario or March 31, 2022.VTEs were identified from emergency department or hospitalization data using ICD-10 codes. Incidence rate of VTEs among individuals with IBD were assessed at 1, 6 and 12 months. Proportional cause-specific hazards models compared the risk of VTEs in people with and without IBD, treating death as a competing risk and controlling for vaccination status (2nd dose ≥14 days prior to positive COVID-19 test) and a history of VTE (VTE in the 5 years prior to infection). Result(s) There were 4293 people with IBD (44% Crohn’s disease, mean age ±SD 46.1±17.2 y) matched to 20,207 with out IBD (mean age 45.3±16.8 y) with a positive SARS-CoV-2 PCR test. Within 1 month of a positive COVID-19 test, the crude incidence rate of VTE in individuals with IBD was 4.77(95%CI, 4.75-4.80) per 100,000 person-days compared to 8.25(95%CI, 8.20-8.30) per 100,000 among people without IBD.Within 6 months, these rates were 1.86(95%CI, 1.86-1.87) and 2.12(95%CI, 2.11-2.12) per 100,000 person-days among people with and without IBD, respectivley. Within 12 months, these rates were 1.59(95% CI, 1.58-1.59) and 1.42(95% CI, 1.42-1.42) per 100,000 person-days among people with and without IBD, respectively.After adjusting for vaccination status and history of VTE there was no difference in the risk of VTE for people with and without IBD (HR 1.08, 95%CI, 0.64 to 1.83). Conclusion(s) IBD patients with COVID-19 were not more likely to experience a VTE infection compared with the general popluation. The risk of VTE was highest soon after COVID-19 and declined thereafter. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

A189 EMERGENCY DEPARTMENT UTILIZATION AND RISK OF INTESTINAL RESECTION IS LOWER AMONG CHILDREN DIAGNOSED WITH INFLAMMATORY BOWEL DISEASE BEFORE 10 YEARS OF AGE: A MULTIPROVINCE POPULATION-BASED COHORT STUDY

Abstract Background In Canada, the incidence of inflammatory bowel disease (IBD) is increasing faster among those &amp;lt;10 years (y) of age than in any other age group. Understanding the health services burden of IBD in this population is important for health system planning. Purpose To compare healthcare utilization and risk of surgery among children diagnosed with IBD across age groups defined by the Paris Classification (A1a: &amp;lt;10y; A1b: 10 to &amp;lt;16y) across 5 Canadian provinces. Method Children diagnosed with IBD &amp;lt;16 years of age were identified from health administrative data using validated algorithms in Alberta, Manitoba, Nova Scotia, Ontario, and Québec. Negative binomial regression models were used to compare (1) the pre-diagnosis frequency of health services utilization (outpatient, emergency department (ED), and hospitalization) using diagnostic codes suggestive of future IBD and (2) the annual post-diagnosis frequency of IBD-specific and IBD-related (signs, symptoms, and extra-intestinal manifestations of IBD) visits among children diagnosed &amp;lt;10y (A1a) and 10 to &amp;lt;16y (A1b). Cox proportional hazard models compared the risk of surgery (identified with validated procedure codes) across age groups. All regression models were adjusted for sex, rural/urban residence, and mean neighbourhood income quintile. Province-specific event counts (all ages combined) and models (comparing age groups; reference: A1b [10 to &amp;lt;16y]) were pooled using random-effects meta-analysis. Result(s) Among 5124 children with IBD (1165 [23%] were &amp;lt;10y at diagnosis), the mean number of pre-diagnosis healthcare encounters was 1.0 (95% CI 0.38 to 1.68, I2=99.6%). The mean annual post-diagnosis number of IBD-specific outpatient visits was 3.2 (95% CI 1.9-4.4, I2=99.6%); hospitalizations, 0.19 (95% CI 0.17-0.21, I2=74%); ED visits, 0.17 (95% CI 0.19-0.39, I2=99%). The mean annual post-diagnosis number of IBD-related outpatient visits was 3.9 (95% CI 2.3-5.5, I2=99.7%); hospitalizations, 0.21 (95% CI 0.19-0.23, I2=79%); ED visits, 0.29 (95% CI 0.19-0.39, I2=97%). Intestinal resection or colectomy within 5y of diagnosis occurred in 13% (95%CI 8-22, I2=93%) with Crohn’s disease (CD) and 16% (95% CI 14-18, I2=40%) with ulcerative colitis. IBD-specific ED visits (RR 0.70, 95% CI 0.50-0.97, I2=80) and the risk of intestinal resection in CD (HR 0.49, 95% CI 0.26-0.92, I2=40%) were significantly lower among children diagnosed &amp;lt;10y. There were no age-related differences in pre-diagnosis health services utilization or other post-diagnosis outcomes, including frequency of outpatient visits to a gastroenterologist. Conclusion(s) Health services utilization was generally similar for children diagnosed with IBD at &amp;lt;10y and between 10 and &amp;lt;16y, except for lower rates of IBD-specific ED visits and intestinal resection in children with CD. Further exploration of between-province differences, represented by the high statistical heterogeneity (I2) in the meta-analyses, is needed to understand sources of variation in care. Please acknowledge all funding agencies by checking the applicable boxes below CCC Disclosure of Interest E. Kuenzig: None Declared, H. Singh Consultant of: Amgen Canada, Bristol-Myers Squibb Canada, Sandoz Canada, Roche Canada, Takeda Canada and Guardant Health, A. Bitton: None Declared, G. Kaplan Grant / Research support from: Ferring, Consultant of: AbbVie, Janssen, Pfizer, Amgen, Sandoz, Pendophram, and Takeda, Speakers bureau of: AbbVie, Janssen, Pfizer, Amgen, Sandoz, Pendophram, and Takeda, M. Carroll: None Declared, A. Otley Grant / Research support from: Research support: AbbVie Global. Research site: AbbVie, Pfizer, Eli-Lily, Janssen, Consultant of: AbbVie Canada, T. Stukel: None Declared, S. Spruin: None Declared, A. Griffiths Grant / Research support from: Abbvie, Consultant of: Abbvie, Amgen, BristolMyersSquibb, Janssen, Lilly, Takeda, Speakers bureau of: Abbvie, Janssen, Takeda, D. Mack: None Declared, K. Jacobson Grant / Research support from: Abbvie Canada and Janssen Canada, Consultant of: Abbvie Canada, Janssen Canada, Merck Canada and Mylan Pharmaceuticals, Speakers bureau of: Abbvie Canada and Janssen Canada, G. Nguyen: None Declared, L. Targownik Grant / Research support from: Janssen Canada, Consultant of: AbbVie Canada, Sandoz Canada, Takeda Canada, Merck Canada, Pfizer Canada, Janssen Canada, and Roche Canada, W. El-Matary Consultant of: Abbvie and MERCK, Speakers bureau of: Abbvie and MERCK, E. Benchimol Consultant of: McKesson Canada, Dairy Farmers of Ontario (unrelated to medications used to treat inflammatory bowel disease)