Surgery In Ontario Research Articles

Long Term Impact of Regionalization of Thoracic Oncology Surgery

In 2007, Cancer Care Ontario created Thoracic Surgical Oncology Standards for the delivery of surgery including lobectomy, esophagectomy and pneumonectomy. These standards regionalized thoracic surgery into designated centers and mandated physical and human resources. This analysis seeks to identify the impact of these standards, hereafter referred to as "regionalization", on outcomes after thoracic oncology surgery in Ontario, Canada. Population-level analysis of patients undergoing lobectomy, esophagectomy or pneumonectomy, using multi-level regression models to compare 30- and 90-day mortality and length of stay length of stay, before, during and after regionalization. Interrupted time series models were used to assess for an impact of regionalization, controlling for ongoing trends. A total of 22,195 surgeries (14,902 lobectomies, 4,958 esophagectomies, and 2,408 pneumonectomies) were performed within the study period. >99% of cases were performed at a designated center post-regionalization. Mean annual volumes per designated center increased post-regionalization for lobectomy and esophagectomy, and decreased for pneumonectomy. 30- and 90-day mortality and length of stay improved for lobectomy and esophagectomy over the study period, as did 90-day mortality for pneumonectomy. However, the interrupted time series analysis did not demonstrate any statistically significant effect of regionalization on these outcomes, separate from pre-existing trends. Consistent improvements in mortality and length of stay in thoracic surgical oncology occurred on a provincial level between 2003-2020, although this analysis does not attribute these improvements to implementation of Thoracic Surgical Oncology Standards including regionalization.

Trends in immediate sequential bilateral cataract surgery in Ontario

ObjectiveBecause of increased evidence for safety and increased demands, there appears to be a recent adoption and endorsement of immediate sequential bilateral cataract surgery (ISBCS). This study aims to determine whether a paradigm shift has occurred in the delivery of cataract surgery in the province of Ontario and its the extent, if any, and to analyze the current role of ISBCS. DesignRetrospective health records analysis. MethodsWe analyzed aggregate Ontario Health Insurance Plan claim counts for cataract surgeries between 2016 and 2022, categorizing cases into unilateral, ISBCS, and delayed sequential bilateral cataract surgery (DSBCS) cases. We examined trends, compared wait times for second surgeries in the DSBCS cohort with wait times for first surgeries, and used previously published cost estimates for ISBCS to estimate annual savings in Ontario. ResultsThere were 1,122 ISBCS cases in 2016, which increased sixfold during the pandemic (2020–2021) and further increased to 11,876 cases in 2022. Unilateral and DSBCS cases decreased during the pandemic but rebounded in 2022 to 102% and 153% of baseline, respectively. ISBCS increased from 1% to 10%, unilateral cases decreased from 41% to 29% of total cases, and DSBCS increased from 58% to 61%. Median wait for patients’ first and second surgeries increased from 65 to 87 days and 28 to 33 days, respectively. Using estimates, ISBCS saved approximately $19 million in 2022. ConclusionOur study demonstrates a paradigm shift in Ontario in favour of ISBCS. ISBCS also may be a strategy to reduce increasing wait times while saving health care system dollars.

Ambulatory Cardiology or General Internal Medicine Assessment Prior to Scheduled Major Vascular Surgery is Associated with Improved Outcomes.

To characterize the association between ambulatory cardiology or general internal medicine (GIM) assessment prior to surgery and outcomes following scheduled major vascular surgery. Cardiovascular risk assessment and management prior to high-risk surgery remains an evolving area of care. This is population-based retrospective cohort study of all adults who underwent scheduled major vascular surgery in Ontario, Canada, April 1, 2004-March 31, 2019. Patients who had an ambulatory cardiology and/or GIM assessment within 6 months prior to surgery were compared to those who did not. The primary outcome was 30-day mortality. Secondary outcomes included: composite of 30-day mortality, myocardial infarction or stroke; 30-day cardiovascular death; 1-year mortality; composite of 1-year mortality, myocardial infarction or stroke; and 1-year cardiovascular death. Cox proportional hazard regression using inverse probability of treatment weighting (IPTW) was used to mitigate confounding by indication. Among 50,228 patients, 20,484 (40.8%) underwent an ambulatory assessment prior to surgery: 11,074 (54.1%) with cardiology, 8,071 (39.4%) with GIM and 1,339 (6.5%) with both. Compared to patients who did not, those who underwent an assessment had a higher Revised Cardiac Risk Index (N with Index over 2= 4,989[24.4%] vs. 4,587[15.4%], P<0.001) and more frequent pre-operative cardiac testing (N=7,772[37.9%] vs. 6,113[20.6%], P<0.001) but, lower 30-day mortality (N=551[2.7%] vs. 970[3.3%], P<0.001). After application of IPTW, cardiology or GIM assessment prior to surgery remained associated with a lower 30-day mortality (weighted Hazard Ratio [95%CI] = 0.73 [0.65-0.82]) and a lower rate of all secondary outcomes. Major vascular surgery patients assessed by a cardiology or GIM physician prior to surgery have better outcomes than those who are not. Further research is needed to better understand potential mechanisms of benefit.

Associations of preoperative anaemia with healthcare resource use and outcomes after colorectal surgery: a population-based cohort study

BackgroundPreoperative anaemia is common in patient undergoing colorectal surgery. Understanding the population-level costs of preoperative anaemia will inform development and evaluation of anaemia management at health system levels. MethodsThis was a population-based cohort study using linked, routinely collected data, including residents from Ontario, Canada, aged ≥18 yr who underwent an elective colorectal resection between 2012 and 2022. Primary exposure was preoperative anaemia (haemoglobin <130 g L−1 in males; <120 g L−1 in females). Primary outcome was 30-day costs in 2022 Canadian dollars (CAD), from the perspective of a publicly funded healthcare system. Secondary outcomes included red blood cell transfusion, major adverse events (MAEs), length of stay (LOS), days alive at home (DAH), and readmissions. ResultsWe included 54,286 patients, with mean 65.3 (range 18–102) years of age and 49.0% females, among which 21 264 (39.2%) had preoperative anaemia. There was an absolute adjusted cost increase of $2671 per person at 30 days after surgery attributable to preoperative anaemia (ratio of means [RoM] 1.05, 95% confidence interval [CI] 1.04–1.06). Compared with the control group, 30-day risks of transfusion (odds ratio [OR] 4.34, 95% CI 4.04–4.66), MAEs (OR 1.14, 95% CI 1.03–1.27), LOS (RoM 1.08, 95% CI 1.07–1.10), and readmissions (OR 1.16, 95% CI 1.08–1.24) were higher in the anaemia group, with reduced DAH (RoM 0.95, 95% CI 0.95–0.96). ConclusionsApproximately $2671 CAD per person in 30-day health system costs are attributable to preoperative anaemia after colorectal surgery in Ontario, Canada.

Surgeon- and hospital-level variation in wait times for scheduled non-urgent surgery in Ontario, Canada: A cross-sectional population-based study.

Canadian health systems fare poorly in providing timely access to elective surgical care, which is crucial for quality, trust, and satisfaction. We conducted a cross-sectional analysis of surgical wait times for adults receiving non-urgent cataract surgery, knee arthroplasty, hip arthroplasty, gallbladder surgery, and non-cancer uterine surgery in Ontario, Canada, between 2013 and 2019. We obtained data from the Wait Times Information System (WTIS) database. Inter- and intra-hospital and surgeon variations in wait time were described graphically with caterpillar plots. We used non-nested 3-level hierarchical random effects models to estimate variation partition coefficients, quantifying the proportion of wait time variance attributable to surgeons and hospitals. A total of 942,605 procedures at 107 healthcare facilities, conducted by 1,834 surgeons, were included in the analysis. We observed significant intra- and inter-provider variations in wait times across all five surgical procedures. Inter-facility median wait time varied between six-fold for gallbladder surgery and 15-fold for knee arthroplasty. Inter-surgeon variation was more pronounced, ranging from a 17-fold median wait time difference for cataract surgery to a 216-fold difference for non-cancer uterine surgery. The proportion of variation in wait times attributable to facilities ranged from 6.2% for gallbladder surgery to 23.0% for cataract surgery. In comparison, surgeon-related variation ranged from 16.0% for non-cancer uterine surgery to 28.0% for cataract surgery. There is extreme variability in surgical wait times for five common, high-volume, non-urgent surgical procedures. Strategies to address surgical wait times must address the variation between service providers through better coordination of supply and demand. Approaches such as single-entry models could improve surgical system performance.

Physician Characteristics Associated With Opioid Prescribing After Same-Day Breast Surgery in Ontario, Canada: A Population-Based Cohort Study.

Opioid overprescribing in patients undergoing breast surgery is a concern, as evidence suggests that minimal or no opioid is needed to manage pain. We sought to describe characteristics of opioid prescribers and determine associations between prescriber's characteristics and high opioid prescribing within 7 days of same-day breast surgery. Patients ≥18 years of age who underwent same-day breast surgery in Ontario, Canada from 2012 to 2020 were identified and linked to prescriber data. The primary outcome was current high opioid prescribing defined as >75th percentile of the mean oral morphine equivalents (OME; milligrams). Prescriber characteristics including age, sex, specialty, years in practice, practice setting, and history of high (>75th percentile) opioid prescribing in the previous year were captured. Associations between prescriber characteristics and the primary outcome were estimated in modified Poisson regression models. The final cohort contained 56,434 patients, 3469 unique prescribers, and 58,656 prescriptions. Over half (1971/3469; 57%) of prescribers wrote ≥1 prescription that was >75th percentile of mean OME of 180 mg, of which 50% were family practice physicians. Adjusted mean OMEs prescribed varied by specialty with family practice specialties prescribing the highest mean OME (614 ± 38 mg) compared to surgical specialties (general surgery [165 ± 9 mg], plastic surgery [198 ± 10 mg], surgical oncology [154 ± 14 mg]). Whereas 73% of first and 31% of second prescriptions were provided by general surgery physicians, family practice physicians provided 2% of first and 51% of second prescriptions. Prescriber characteristics associated with a higher likelihood of high current opioid prescribing were family practice (risk ratio [RR], 1.56; 95% confidence interval [CI], 1.35-1.79 compared to general surgery), larger community practice setting (RR, 1.34; 95% CI, 1.05-1.71 compared to urban), and a previous high opioid prescribing behavior (RR, 2.28; 95% CI, 2.06-2.52). While most studies examine surgeon opioid prescribing, our data suggest that other specialties contribute to opioid overprescribing in surgical patients and identify characteristics of physicians likely to overprescribe.

Trends in newly diagnosed atrial fibrillation and oral anticoagulant use after cardiac surgery: a population-based analysis from Ontario, Canada

Abstract Background Post-operative atrial fibrillation after cardiac surgery is associated with an increased risk of death and ischemic cardiovascular outcomes. In the non-surgical setting, oral anticoagulation (OAC) is beneficial among patients with AF in reducing their risk of thromboembolism. The use of OAC for patients with post-operative AF after cardiac surgery is not well-defined in contemporary clinical practice - at a time when direct oral anticoagulants (DOAC) are commonly prescribed in the non-surgical setting. Purpose To examine trends in OAC use among patients with post-operative atrial fibrillation after cardiac surgery at a time when DOAC is commonly prescribed in clinical practice. Methods The study cohort consisted of consecutive patients (&amp;gt;65 years) who experienced post-operative AF within 90 days after coronary artery bypass grafting (CABG), isolated left-sided non-mechanical heart valve surgery (iValve), and combined CABG + valve surgery between 2008 and 2021, identified by a mandatory provincial registry of all patients undergoing cardiac surgery in Ontario, Canada. Key exclusion criteria included: patients with pre-existing AF, end-stage renal disease requiring dialysis, mechanical heart valves, left atrial appendage ligation, and those who required anticoagulation for non-AF indications. Prescription of OAC (warfarin or DOAC) within 90 days after discharge from surgery was collected via linkage with the Ontario Drug Benefits Plan. Results The overall cohort consisted of 45,571 patients, in whom 14,572 (32.0%) developed POAF after cardiac surgery. Rates of POAF were highest among patients who underwent combined CABG + valve surgery (44.3% in 2008 to 34.2% in 2021), followed by iValve (42.6% in 2008 to 37.3% in 2021), then followed by isolated CABG (27.6% in 2008 to 24.2% in 2021). Over the study period, there was a decrease in the rates of POAF among patients who underwent all three types of cardiac surgery (P[trend] &amp;lt;0.01). In 2021, rates of oral anticoagulation were highest among patients who underwent combined CABG + valve surgery (61.1%), followed by iValve (59.2%) and isolated CABG (42.0%). Among patients who underwent isolated CABG, there was a 9% increase in the rates of OAC use during the study period (P[trend] &amp;lt;0.001). On the other hand, rates of OAC use remained largely unchanged (Figure A) among patients who underwent iValve and combined CABG + valve surgery (P[trend] 0.24 and 0.26, respectively). Since 2018, DOAC accounted for 60-70% of all OAC prescriptions (Figure B). Conclusions Despite advances in surgical techniques and post-operative care, the rates of post-operative atrial fibrillation after cardiac surgery remain substantial. Prescription rates for OAC remain modest over the past decade, but DOAC is increasingly more commonly prescribed in this patient population. Randomized trials are needed to assess the risks and benefits of OAC, specifically DOAC, in this high-risk patient population.Figure AFigure B

Impact of a Transitional Pain Service on postoperative opioid trajectories: a retrospective cohort study

IntroductionIt has been well described that a small but significant proportion of patients continue to use opioids months after surgical discharge. We sought to evaluate postdischarge opioid use of patients...

Time trends and patterns in opioid prescription use following orthopaedic surgery in Ontario, Canada, from 2004/2005 to 2017/2018: a population-based study

ObjectivesIncreased use of opioids and their associated harms have raised concerns around prescription opioid use for pain management following surgery. We examined trends and patterns of opioid prescribing following elective...

Social determinants of access to timely elective surgery in Ontario, Canada: a cross-sectional population level study.

Equitable access to surgical care has clinical and policy implications. We assess the association between social disadvantage and wait times for elective surgical procedures in Ontario. We conducted a cross-sectional analysis using administrative data sets of adults receiving nonurgent inguinal hernia repair, cholecystectomy, hip arthroplasty, knee arthroplasty, arthroscopy, benign uterine surgery and cataract surgery from April 2013 to December 2019. We assessed the relation between exceeding target wait times and the highest versus lowest quintile of marginalization dimensions by use of generalized estimating equations logistic regression. Of the 1 385 673 procedures included, 174 633 (12.6%) exceeded the target wait time. Adjusted analysis for cataract surgery found significantly increased odds of exceeding wait times for residential instability (adjusted odd ratio [OR] 1.16, 95% confidence interval [CI] 1.11-1.21) and recent immigration (adjusted OR 1.12, 95% CI 1.07-1.18). The highest deprivation quintile was associated with 18% (adjusted OR 1.18, 95% CI 1.12-1.24) and 20% (adjusted OR 1.20, 95% CI 1.12-1.28) increased odds of exceeding wait times for knee and hip arthroplasty, respectively. Residence in areas where higher proportions of residents self-identify as being part of a visible minority group was independently associated with reduced odds of exceeding target wait times for hip arthroplasty (adjusted OR 0.82, 95% CI 0.75-0.91), cholecystectomy (adjusted OR 0.68, 95% CI 0.59-0.79) and hernia repair (adjusted OR 0.65, 95% CI 0.56-0.77) with an opposite effect in benign uterine surgery (adjusted OR 1.28, 95% CI 1.17-1.40). Social disadvantage had a small and inconsistent impact on receiving care within wait time targets. Future research should consider these differences as they relate to resource distribution and the organization of clinical service delivery.

A Frailty Index to Predict Mortality, Resource Utilization and Costs in Patients Undergoing Coronary Artery Bypass Graft Surgery in Ontario

BackgroundPeople living with frailty are vulnerable to poor outcomes and incur higher health care costs after coronary artery bypass graft (CABG) surgery. Frailty-defining instruments for population-level research in the CABG setting have not been established. The objectives of the study were to develop a preoperative frailty index for CABG (pFI-C) surgery using Ontario administrative data; assess pFI-C suitability in predicting clinical and economic outcomes; and compare pFI-C predictive capabilities with other indices. MethodsA retrospective cohort study was conducted using health administrative data of 50,682 CABG patients. The pFI-C comprised 27 frailty-related health deficits. Associations between index scores and mortality, resource use and health care costs (2022 Canadian dollars [CAD]) were assessed using multivariable regression models. Capabilities of the pFI-C in predicting mortality were evaluated using concordance statistics; goodness of fit of the models was assessed using Akakie Information Criterion. ResultsAs assessed by the pFI-C, 22% of the cohort lived with frailty. The pFI-C score was strongly associated with mortality per 10% increase (odds ratio [OR], 3.04; 95% confidence interval [CI], [2.83,3.27]), and was significantly associated with resource utilization and costs. The predictive performances of the pFI-C, Charlson, and Elixhauser indices and Johns Hopkins Aggregated Diagnostic Groups were similar, and mortality models containing the pFI-C had a concordance (C)-statistic of 0.784. Cost models containing the pFI-C showed the best fit. ConclusionsThe pFI-C is predictive of mortality and associated with resource utilization and costs during the year following CABG. This index could aid in identifying a subgroup of high-risk CABG patients who could benefit from targeted perioperative health care interventions.

Defining Standards for Hepatopancreatobiliary Cancer Surgery in Ontario, Canada: A Population-Based Cohort Study of Clinical Outcomes.

In 2006, Cancer Care Ontario created Surgical Oncology Standards for the delivery of hepatopancreatobiliary (HPB) surgery including hepatectomy and pancreaticoduodenectomy (PD). Our objective was to identify the impact of standardization on outcomes after HPB surgery in Ontario, Canada. This study was a population-level analysis of patients undergoing hepatectomy or PD (2003 to 2019). Logistic regression models were used to compare 30- and 90-day mortality and length of stay (LOS) before (2003 to 2006), during (2007 to 2011), and after (2012 to 2019) standardization. Interrupted time series models were used to co-analyze secular trends. A total of 7,904 hepatectomies and 5,238 PDs were performed. More than 80% of all cases were performed at a designated center (DC) before standardization. This increased to >98% in the poststandardization era. Median volumes at DCs increased from 55 to 67 hepatectomies/year and from 22 to 50 PDs/year over time. In addition, 30-day mortality after hepatectomy was 2.6% before standardization and 2.3% after standardization (p = 0.9); 30-day mortality after PD was 3.6% before standardization and 2.4% after standardization (p = 0.1). Multivariable analyses revealed a significant difference in 90-day mortality following PD poststandardization (4.3% vs 6.3%; adjusted odds ratio, 0.7; p = 0.03). Median LOS was shorter for hepatectomy (6 days vs 8 days) and PD (9 days vs 14 days; p < 0.0001) after standardization. Immediate and late effects on mortality and LOS were likely attributable to secular trends, which predated standardization. Standardization was associated with a higher volume of hepatectomy and PDs with further concentration of care at DCs. Pre-existing quality initiatives may have attenuated the effect of standardization on quality outcomes. Our data highlight the merits of a multifaceted provincial system for enabling consistent access to high quality HPB care throughout a region of 15 million people over a 16-year period.

Association of preoperative anaesthesia consultation prior to elective noncardiac surgery with patient and health system outcomes: a population-based study

BackgroundSurgical volumes and use of preoperative anaesthesia consultations are increasing. However, contemporary data estimating the association between preoperative anaesthesia consultation and patient (days alive and at home [DAH30], mortality) and system (costs, length of stay, and readmissions) outcomes are not available. MethodsWe conducted a population-based comparative effectiveness study using linked health administrative data among patients aged ≥40 yr who underwent intermediate-risk to high-risk elective, inpatient, noncardiac surgery in Ontario, Canada (2009–17). Our primary outcome was DAH30. Secondary outcomes included DAH90, 30-day and 1-yr mortality, 30-day health system costs, length of index admission, and 30-day readmissions. Propensity score overlap weights were used to adjust for confounders. Prespecified effect modifier analyses focused on high-risk subgroups. ResultsAmong 364 149 patients, 274 365 (75.3%) received a preoperative anaesthesia consultation. No adjusted association was found (22.5 days vs 22.5 days; adjusted ratio of means 1.00, 95% CI 1.00–1.00) between consultation and DAH30 in the full population. We identified significant effect modification (significantly more DAH30) among patients with ischaemic heart disease, ASA physical status ≥4, frailty index score ≥0.21, and who underwent vascular surgery. Secondary outcomes were associated with preoperative consultation, including greater DAH90, decreased length of stay, lower 30-day and 1-yr mortality, and reduced 30-day costs. ConclusionsPreoperative anaesthesia consultation was not associated with greater DAH30 across the overall study population. However, important potential benefits were observed among high-risk subgroups. Research is needed to identify optimal patient populations and consultation processes.

The Impact of the COVID-19 Pandemic on Wait-Times for Ophthalmic Surgery in Ontario, Canada: A Population-Based Study.

To investigate the effects of the COVID-19 pandemic on case volumes and wait-times for ophthalmic surgery in Ontario, Canada. Population-based retrospective cohort study. Patients undergoing ophthalmic surgery in Ontario, Canada, from 2010 to 2021, collected from the Ontario Health Wait Times Information System (WTIS) database. The WTIS contains non-emergent surgical case volume and wait-time data for six ophthalmic subspecialty surgery types, three priority levels (low, medium, high) and 14 different regions in Ontario. Case volume and wait-times were compared between the COVID-19 pandemic (2020-2021) and the preceding time period (2010-2019) across all stratifications. There was a significant decrease in case volumes and significant increase in wait-times across geographic regions, priority levels, and subspecialty surgeries from the pre-pandemic to pandemic period. Moreover, COVID-19 exacerbated pre-existing wait-time disparities between sexes, with females waiting 4.1 days longer than males overall to receive surgery in 2010-2019 compared to waiting 8.8 days longer in 2020-2021 (117% increase). These findings highlight the impact of the COVID-19 pandemic on ophthalmic surgical wait times in Ontario. Cataract, strabismus and oculoplastic surgeries, the Waterloo Wellington, Central, and South East regions of Ontario, and those with female sex had the greatest relative increases in wait-times during the pandemic.

Demographic trends of patients undergoing ophthalmic surgery in Ontario, Canada: a population-based study

ObjectiveIn this study, we investigated the demographic trends of patients undergoing ophthalmic surgeries based on geographic region, priority level, and sex.Methods and analysisThis population-based retrospective cohort study used the Ontario...

Patient reported symptom burden amongst immigrant and Canadian long-term resident women undergoing breast cancer surgery.

Immigrants are susceptible to marginalization due to social isolation, economic disadvantage and systemic bias. Our goal was to compare symptom burden between immigrant and long-term resident women undergoing breast cancer surgery in Ontario, Canada. A population-level retrospective cohort-study using administrative databases was conducted. Women who underwent surgery for newly diagnosed breast cancer and were treated at regional cancer centers between 2010 and 2016 were included. The primary outcome was a moderate or severe (≥ 4) symptom score on the Edmonton Symptom Assessment System Scale (ESAS). There were 12,250 (87.2%) long-term Canadian residents and 1,806(12.8%) immigrants. Immigrants were younger (mean age 53 vs. 61years); had a higher proportion residing in a lowest income quintile neighbourhood (22.2% vs 15.4%); were less often on a primary-care physician roster (83.7% vs. 90.4%); and were less often diagnosed with Stage I/II disease (80.9% vs. 84.6%) (all p < 0.01). The proportion of women with scores ≥ 4 was significantly higher amongst immigrant women for 7/9 symptom categories; with the largest differences for depression (24.9% vs. 20.2%, p < 0.01) and pain (28.0% vs. 22.4%, p < 0.01). On multivariable regression analysis, immigration status was associated with scores ≥ 4 for pain (OR 1.13, 95% CI 1.02-1.23). There was an association between moderate/severe pain and region of origin, but not length of stay in Canada or immigration class. This is the first study comparing symptom burden amongst immigrant and non-immigrant women with breast cancer at a population-level. Immigrant women with breast cancer undergoing surgery were found to have a higher burden of pain.

Variation in opioid filling after same-day breast surgery in Ontario, Canada: a population-based cohort study.

Postoperative pain management practices in breast surgery are variable, with recent evidence that approaches for minimizing or sparing opioids can be successfully implemented. We describe opioid filling and predictors of higher doses in patients undergoing same-day breast surgery in Ontario, Canada. In this retrospective population-based cohort study, we used linked administrative health data to identify patients aged 18 years or older who underwent same-day breast surgery from 2012 to 2020. We categorized procedure types by increasing invasiveness of surgery: partial, with or without axillary intervention (P ± axilla); total, with or without axillary intervention (T ± axilla); radical, with or without axillary intervention (R ± axilla); and bilateral. The primary outcome was filling an opioid prescription within 7 or fewer days after surgery. Secondary outcomes were total oral morphine equivalents (OMEs) filled (mg, median and interquartile range [IQR]) and filling more than 1 prescription within 7 or fewer days after surgery. We estimated associations (adjusted risk ratios [RRs] and 95% confidence intervals [CIs]) between study variables and outcomes in multivariable models. We used a random intercept for each unique prescriber to account for provider-level clustering. Of the 84 369 patients who underwent same-day breast surgery, 72% (n = 60 620) filled an opioid prescription. Median OMEs filled increased with invasiveness (P ± axilla = 135 [IQR 90-180] mg; T ± axilla = 135 [IQR 100-200] mg; R ± axilla = 150 [IQR 113-225] mg, bilateral surgery = 150 [IQR 113-225] mg; p < 0.0001). Factors associated with filling more than 1 opioid prescription were age 30-59 years (v. age 18-29 yr), increased invasiveness (RR 1.98, 95% CI 1.70-2.30 bilateral v. P ± axilla), Charlson Comorbidity Index ≥ 2 versus 0-1 (RR 1.50, 95% CI 1.34-1.69) and malignancy (RR 1.39, 95% CI 1.26-1.53). Most patients undergoing same-day breast surgery fill an opioid prescription within 7 days. Efforts are needed to identify patient groups where opioids may be successfully minimized or eliminated.

Abstract P4-03-28: Patient Reported Symptom Burden Amongst Immigrant and Canadian Long-Term Resident Women Undergoing Breast Cancer Surgery

Abstract Background: Disparities in breast cancer outcomes are well documented, with a burgeoning body of literature shedding light on the influence of multiple factors. Much of the literature comes from the US, with the current situation in Canada less well understood. Canada’s universal health care system may mitigate some, but unlikely all differences. First generation immigrants compromise 21.9% of the Canadian population. Differences in breast cancer screening rates and stage at diagnosis have been demonstrated between immigrant and non-immigrant Canadian women. However, breast cancer outcomes in the Canadian immigrant population have not been well studied. Patient reported outcomes are one such set of outcomes and crucial in understanding the patient experience. The purpose of this study is to compare symptom burden and trajectories between immigrant and Canadian long-term resident women with breast cancer undergoing breast cancer surgery in Ontario. Methods: A population-level retrospective cohort-study using linked Ontario administrative databases was constructed. Women &amp;gt;18 years of age with newly diagnosed breast cancer between 2010-2016 undergoing surgery at a regional cancer center were included. Baseline variables including immigration status, age, stage, comorbidity and income quintile were collected. The proportion of patients reporting moderate/severe Edmonton Symptom Assessment System Scale (ESAS) scores for each of 9 individual symptom categories over time was collected. Multivariable logistic regression models using generalized estimating equations with exchangeable correlation structure to account for repeated measures were constructed to assess the probability of a moderate/severe score for each of the individual ESAS symptom categories. Results: The cohort included 14,056 women, of which 12,250 (87.2%) were categorized as long-term Canadian residents and 1,806 (12.8%) as immigrants. Immigrant women had a younger mean age of diagnosis (53 vs. 61 years), were more likely to reside in a lowest income quintile neighbourhood (22.2% vs 15.4%), were less likely to be on a primary care physician roster within the last 2 years (83.7% vs. 90.4%) and were less often diagnosed with Stage I/II disease (80.9% vs. 84.6%) (all p&amp;lt; 0.0001). The proportion of women reporting moderate/severe scores was significantly higher amongst immigrant women for 7/9 symptom categories (anxiety, depression, drowsiness, nausea, pain, shortness of breath and well-being) with the largest difference observed for depression (13.1% vs 10.8%, p&amp;lt; 0.0001) and pain (14.8% vs. 12.0%, p&amp;lt; 0.0001). Comparing symptom trajectories, differences between groups were most pronounced within the first 12 months, though for depression and pain, statistically significant differences also existed at 36 months. On multivariable regression analysis, immigration status was persistently associated with higher proportion of moderate/severe score for pain only (OR 1.12, 95% CI 1.02-1.23). Immigration status was associated with a protective effect for anxiety (OR 0.86, 95% CI 0.78-0.94), drowsiness (OR 0.81, 95% CI 0.73-0.89) and tiredness (OR 0.86, 95% CI 0.79-0.94). Conclusions: To our knowledge, this is the first study comparing symptom burden amongst immigrant and non-immigrant Canadian women with breast cancer at a population-level. Immigrant women undergoing breast cancer surgery were found to have a higher burden of symptoms across most categories, and for depression and pain this difference was found to persist even at 3-years. However, the higher burden of symptoms in many categories seemed to be explained by factors such as younger age and more advanced disease. Adjusting for other factors, immigrant women with breast cancer reported more pain, indicating a need for better symptom management in this population. Citation Format: Elena Parvez, Megan M. Chu, David Kirkwood, Aristithes Doumouras, Jessica Bogach. Patient Reported Symptom Burden Amongst Immigrant and Canadian Long-Term Resident Women Undergoing Breast Cancer Surgery. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-03-28.

A retrospective population-based analysis of wait times for cataract surgery in Ontario, Canada.

Current methods used to estimate surgical wait times in Ontario may be subject to inconsistencies and inaccuracies. In this population-level study, we aimed to estimate cataract surgery wait times in Ontario using a novel, objective and data-driven method. We identified adults who underwent cataract surgery between 2005 and 2019 in Ontario, using administrative records. Wait time 1 represented the number of days from referral to initial visit with the surgeon, and wait time 2 represented the number of days from the decision for surgery until the first eye surgery date. In the primary analysis, a ranking method prioritized referrals from optometrists, followed by ophthalmologists and family physicians. The cohort consisted of 1 138 532 people with mostly female patients (57.4%) and those aged 65 years and older (79.0%). In the primary analysis, the median was 67 days for wait time 1 (interquartile range [IQR] 29-147). There was a median of 77 days for wait time 2 (IQR 37-155). Overall, the following proportions of patients waited less than 3, 6 and 12 months: 54.1%, 78.5% and 91.7%, respectively. For wait time 2, the proportions of patients who waited less than 3, 6 and 12 months were 49.5%, 77.1% and 93.3%, respectively. In total, 19.3% of patients did not meet the provincial target for wait time 1, 20.5% did not meet the target for wait time 2 and 35.0% did not meet the target for wait times 1 or 2. Administrative health services data can be used to estimate cataract surgery wait times. With this method, 35.0% of patients in 2005-2019 did not receive initial consultation or surgery within the provincial wait time target.

Survival and health care costs after inpatient elective surgery: comparison of patients with and without chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is common among surgical patients, and patients with COPD have higher risk for complications and death within 30 days after surgery. We sought to describe the longer-term postoperative survival and costs of patients with COPD compared with those without COPD within 1 year after inpatient elective surgery. In this retrospective population-based cohort study, we used linked health administrative databases to identify all patients undergoing inpatient elective surgery in Ontario, Canada, from 2005 to 2019. We ascertained COPD status using validated definitions. We followed participants for 1 year after surgery to evaluate survival and costs to the health system. We quantified the association of COPD with survival (Cox proportional hazards models) and costs (linear regression model with log-transformed costs) with partial adjustment (for sociodemographic factors and procedure type) and full adjustment (also adjusting for comorbidities). We assessed for effect modification by frailty, cancer and procedure type. We included 932 616 patients, of whom 170 482 (18%) had COPD. With respect to association with risk of death, COPD had a partially adjusted hazard ratio (HR) of 1.61 (95% confidence interval [CI] 1.58-1.64), and a fully adjusted HR of 1.26 (95% CI 1.24-1.29). With respect to impact on health system costs, COPD was associated with a partially adjusted relative increase of 13.1% (95% CI 12.7%-13.4%), and an increase of 4.6% (95% CI 4.3%-5.0%) with full adjustment. Frailty, cancer and procedure type (such as orthopedic and lower abdominal surgery) modified the association between COPD and outcomes. Patients with COPD have decreased survival and increased costs in the year after surgery. Frailty, cancer and the type of surgical procedure modified associations between COPD and outcomes, and must be considered when risk-stratifying surgical patients with COPD.