Institute For Clinical Evaluative Sciences Research Articles

Direct Oral Anticoagulation Versus Warfarin in Patients with Atrial Fibrillation and Bioprosthetic Heart Valves: a Retrospective, Real-World Cohort Study.

In this retrospective cohort study of consecutive patients with atrial fibrillation and surgical or transcatheter bioprosthetic valve, we compared the efficacy and safety of direct oral anticoagulants withwarfarin. Using linked health administrative databases housed at the Institute for Clinical Evaluative Sciences, we identified consecutive patients in Ontario (Canada) 65years of age or older with AF who underwent bioprosthetic valve replacement between 1 April 2012 and 31 March 2017. We created a time-varying Cox model to examine the relationship between the type of anticoagulant and time to thrombotic or bleeding events after adjustment for baseline risk of thrombosis using the CHA2DS2-VASc score and risk ofbleeding using the HAS-BLED scores. We conductedprespecified subgroup analyses according to whether valve implantation was surgical or transcatheter. We identified 2245 eligible patients. The mean age was 79years, 41% were female, and 39% had transcatheter aortic valve replacement. Risk of death or thrombosis was not differentbetween direct oral anticoagulants and warfarin after adjustment for CHA2DS2-VASc score (hazard ratio [HR] 1.02, 95% confidence interval [CI], 0.83-1.25). Risk of death or bleeding was not differentbetween direct oral anticoagulants and warfarin after adjustment for HAS-BLED score (HR 0.89, 95% CI 0.75-1.07). Subgroup analyses of surgical or transcatheter valves were consistent with overall results. In a real-world population of patients with atrial fibrillation and bioprosthetic valve replacement, we foundno difference between direct oral anticoagulants and warfarin with regard to the risk of thrombosis or bleeding.

Determining the incidence of postpartum haemorrhage among Ontario women with and without inherited bleeding disorders: A population-based cohort study.

At a population level, there is a poor understanding of the incidence and pre-disposing risk factors of postpartum haemorrhage (PPH) among women with inherited bleeding disorders (IBD). To determine the incidence of PPH, and identify maternal factors associated with risk of PPH among women with IBD. We conducted a retrospective cohort study using data housed within ICES (formerly known as the Institute for Clinical Evaluative Sciences). The cohort included women with an in-hospital, live or stillborn delivery, between January 2014 and December 2019. The primary outcome was PPH (identified by ICD-10 code O72). PPH incidence and risk factors were compared between women with and without IBD. Temporal trends were assessed using the Cochrane-Armitage test. Between group differences were assessed using standardised differences (std. difference). Total 601,773 women were included; 2002 (.33%) had an IBD diagnosis. PPH incidence was 1.5 times higher (7.3 vs. 4.9 cases/100 deliveries, std. difference .1) among women with IBD compared to women without. Women with IBD were slightly older (31.7 vs. 30.7 years), had higher rates of hypertension, previous PPH, and induction of labour. Women with IBD were more frequently diagnosed with anaemia (4.8% vs. 1.8%; std difference .17) and had lower haemoglobin levels at admission for delivery compared to women without IBD. This study contributes to the literature regarding obstetric bleeding among women with IBD, showing that anaemia at delivery may be an important risk factor for PPH. Given their predisposition to anaemia, clarifying this relationship will optimise management and outcomes.

The real-world experience of adjuvant docetaxel and cyclophosphamide (TC) chemotherapy in HER-2 negative breast cancer.

538 Background: Adjuvant chemotherapy in breast cancer (BC) substantially improves overall survival (OS) and the risk of recurrence. The short and long-term side effects of anthracycline, and its modest benefits in the adjuvant setting, led to controversy about its role in comparison with TC. We aim to compare the OS of TC with anthracycline-based regimens in Ontario, the most populous province in Canada. Methods: We conducted a retrospective population-based cohort study using the Institute for Clinical Evaluative Sciences (ICES) database, involving females with stage I-III BC HER2-negative. Patients were treated with adjuvant chemotherapy between January 2009 to December 2017. The anthracycline regimens for comparison were as follows, FEC-D: Fluorouracil, Epirubicin, Cyclophosphamide, followed by Docetaxel; and ACT: Doxorubicin, Cyclophosphamide, followed by Docetaxel or Paclitaxel. Exclusion criteria included missing baseline characteristics, a prior history of malignancy or chemotherapy starting more than 120 days from breast surgery. The end of follow-up was March 31st, 2018. Adjusted analyses to compare OS by positive axillary lymph nodes (LN) and chemotherapy regimens were conducted with Cox proportional hazards models. Results: Of a total 10634 female patients with BC, 60% were ≥ 50 years-old, with 19.6% stage I, 61.1% stage II, and 19.3% stage III and 7130 (67%) women were classified as ER+ and 2379 (22.4%) as ER-. Among 5764 (54.2%) patients with positive LN, 4300 (40.4%) had LN 1-3 and 1464 (13.8%) had LN ≥ 4. There were 4945 (46.5%) high-grade cases. There were 2487 (23.5%) patients treated with TC, 2981 (28%) with ACT, and 5166 (48.5%) with FEC-D. With a median follow-up of 5.5 years, the OS comparison for the entire study population showed hazard ratio (HR) of TC vs ACT was 1.47 (95% CI 1.14 – 1.90), p = 0.0027 and TC vs FEC-D HR was 1.48 (95% CI 1.18 – 1.86), p = 0.0007. For ER+ patients treated with TC, the OS comparison of LN 1-3 and LN ≥ 4 vs. LN 0 showed HR 1.34 (95% CI 0.81 – 2.21), p = 0.26, and HR 4.29 (95% CI 2.09 – 8.79), p < 0.0001, respectively. For ER+ LN 0 patients, the OS HR of TC vs. ACT was 1.15 (95% CI 0.58 – 2.35), p = 0.67, and TC vs. FEC-D HR was 1.38 (95% CI 0.81 – 2.33), p = 0.23. For ER- patients treated with TC, the OS comparison of LN 1-3 and LN ≥ 4 vs. LN 0 showed HR 1.12 (95% CI 0.42 – 3.01), p = 0.82 and HR 4.41 (95% CI 1.33 – 14.59), p = 0.015, respectively. For ER- LN 0 patients, the OS HR for TC vs. ACT was 2.04 (95% CI 1.09 – 3.81), p = 0.025, and TC vs. FEC-D HR was 2.05 (95% CI 1.08 – 3.90), p = 0.028. Conclusions: Patients treated with adjuvant TC who had four or more axillary LN had significantly lower OS when compared to patients with LN 0. For women with ER- disease, TC demonstrated a significant unfavourable survival outcome when compared to anthracycline-based treatments.

Association of Late Preterm Birth and Size for Gestational Age With Cardiometabolic Risk in Childhood

The long-term cardiometabolic consequences of late preterm birth (34-36 weeks' gestation) are not well understood. To assess whether late preterm birth and size for gestational age are associated with cardiometabolic risk (CMR) in childhood. This retrospective cohort study included 1742 children born in Ontario, Canada, between April 1, 2006, and September 30, 2014, and followed up until September 30, 2019. Data from children enrolled in The Applied Research Group for Kids (TARGet Kids!) primary care practice-based research network were linked to administrative health care data at ICES (formerly known as the Institute for Clinical Evaluative Sciences). Participants were excluded if they had conditions affecting growth (eg, failure to thrive or cystic fibrosis), any acute or chronic conditions (other than asthma and high-functioning autism), severe developmental delay, or families who were unable to communicate in English. Late preterm birth, gestational age as a continuous measure, and size for gestational age. The primary outcome was composite CMR score (overall age- and sex-standardized z score of CMR components, including waist circumference, log triglyceride level, glucose level, systolic blood pressure, and high-density lipoprotein cholesterol level). Secondary outcomes were the individual CMR components. Multivariable linear regression analysis was used to separately evaluate the associations of late preterm birth, continuous gestational age, and size for gestational age with CMR at ages 3 to 12 years. Among 2440 eligible children, 1742 (mean [SD] age, 5.6 [2.2] years; 951 boys [54.6%]) were included in the final cohort. Overall, 87 children (5.0%) were born moderately preterm (<34 weeks' gestation), 145 (8.3%) were born late preterm (34-36 weeks' gestation), 455 (26.1%) were born early term (37-38 weeks' gestation), and 1055 (60.6%) were born full term (≥39 weeks' gestation). Compared with children born full term, those born moderately preterm (adjusted β = 0.50; 95% CI, 0.24-0.75) and late preterm (adjusted β = 0.27; 95% CI, 0.06-0.47) had higher CMR scores. Each additional gestational week was associated with a 0.06 U (adjusted β; 95% CI, -0.08 to -0.03 U) decrease in CMR. In this study, children born late preterm and moderately preterm had higher CMR. These results suggest that screening and early-life interventions for these children may prevent cardiometabolic outcomes.

Are Income-based Differences in TKA Use and Outcomes Reduced in a Single-payer System? A Large-database Comparison of the United States and Canada.

Income-based differences in the use of and outcomes in TKA have been studied; however, it is not known if different healthcare systems affect this relationship. Although Canada's single-payer healthcare system is assumed to attenuate the wealth-based differences in TKA use observed in the United States, empirical cross-border comparisons are lacking. (1) Does TKA use differ between Pennsylvania, USA, and Ontario, Canada? (2) Are income-based disparities in TKA use larger in Pennsylvania or Ontario? (3) Are TKA outcomes (90-day mortality, 90-day readmission, and 1-year revision rates) different between Pennsylvania and Ontario? (4) Are income-based disparities in TKA outcomes larger in Pennsylvania or Ontario? We identified all patients hospitalized for primary TKA in this cross-border retrospective analysis, using administrative data for 2012 to 2018, and we found a total of 161,244 primary TKAs in Ontario and 208,016 TKAs in Pennsylvania. We used data from the Pennsylvania Health Care Cost Containment Council, Harrisburg, PA, USA, and the ICES (formally the Institute for Clinical Evaluative Sciences), Toronto, Ontario, Canada. We linked patient-level data to the respective census data to determine community-level income using ZIP Code or postal code of residence and stratified patients into neighborhood income quintiles. We compared TKA use (age and gender, standardized per 10,000 population per year) for patients residing in the highest-income versus the lowest-income quintile neighborhoods. Similarly secondary outcomes 90-day mortality, 90-day readmission, and 1-year revision rates were compared between the two regions and analyzed by income groups. TKA use was higher in Pennsylvania than in Ontario overall and for all income quintiles (lowest income quartile: 31 versus 18 procedures per 10,000 population per year; p < 0.001; highest income quartile: 38 versus 23 procedures per 10,000 population per year; p < 0.001). The relative difference in use between the highest-income and lowest-income quintile was larger in Ontario (28% higher) than in Pennsylvania (23% higher); p < 0.001. Patients receiving TKA in Pennsylvania were more likely to be readmitted within 90 days and were more likely to undergo revision within the first year than patients in Ontario, but there was no difference in mortality at 1 year. When comparing income groups, there were no differences between the countries in 90-day mortality, readmission, or 1-year revision rates (p > 0.05). These results suggest that universal health insurance through a single-payer may not reduce the income-based differences in TKA access that are known to exist in the United States. Future studies are needed determine if our results are consistent across other geographic regions and other surgical procedures. Level III, therapeutic study.

Practice Profiles and Patterns of Ontario Family Medicine Residents 5 Years After Residency Examinations: An Exploratory Study.

The primary goal of family medicine residency training is for graduates to provide high-quality, safe, and effective patient care for the population they serve when they enter practice. This study explores (a) the practice profiles, 5 years into practice, of residents who completed family medicine training in Ontario, Canada; and (b) relationships between performance on the College of Family Physicians of Canada's (CFPC) Certification Examination in Family Medicine and quality of care provided 5 years into practice. We performed a retrospective study with secondary data analysis. We merged CFPC examination data sets with the ICES (Institute for Clinical Evaluative Sciences) administrative database. We included physicians who passed the examination between the years 2000 and 2010 and practiced in Ontario after graduation. Practice profile indicators included practice type, continuity and comprehensiveness of care, patient rostering and panel size, and rurality index. We explored11 indicators related to management of diabetes and cancer screening. We included a total of 1,983 physicians in the analyses. Five years after the examinations, 74.3% of the physicians were working in major urban centers, and 67.3% of the physicians were providing comprehensive primary care. We noted significant differences across the six medical schools in multiple practice profile indicators, and three indicators showed significant differences across the examination score quintiles. Graduates of Ontario family medicine residency programs were providing care to a broad spectrum of the population 5 years after passing the examination, and they performed similarly across quality-of-care indicators regardless of examination scores.

Printed educational materials directed at Ontario family physicians do not improve adherence to guideline recommendations for diabetes management: a pragmatic, factorial, cluster randomized controlled trial [ISRCTN72772651

BackgroundPrinted educational materials (PEMs) have long been used to inform clinicians on evidence-based practices. However, the evidence for their effects on patient care and outcomes is unclear. In Ontario, despite widely available clinical practice guidelines recommending antihypertensives and cholesterol-lowering agents for patients with diabetes, prescriptions remain low. We aimed to determine whether PEMs can influence physicians to intensify prescribing of these medications.MethodsA pragmatic, 2 × 2 factorial, cluster randomized controlled trial was designed to ascertain the effect of two PEM formats on physician prescribing: a postcard-sized message (“outsert”) or a longer narrative article (“insert”). Ontario family physician practices (clusters) were randomly allocated to receive the insert, outsert, both or neither. Physicians were eligible if they were in active practice and their patients were included if they were over 65 years with a diabetes diagnosis; both were unaware of the trial. Administrative databases at ICES (formerly the Institute for Clinical Evaluative Sciences) were used to link patients to their physician and to analyse prescribing patterns at baseline and 1 year following PEM mailout. The primary outcome was intensification defined as the addition of a new antihypertensive or cholesterol-lowering agent, or dose increase of a current drug, measured at the patient level. Analyses were by intention-to-treat and accounted for the clustering of patients to physicians.ResultsWe randomly assigned 4231 practices (39% of Ontario family physicians) with a total population of 185,526 patients (20% of patients with diabetes in Ontario primary care) to receive the insert, outsert, both, and neither; among these, 4118 practices were analysed (n = 1025, n = 1037, n = 1031, n = 1025, respectively). No significant treatment effect was found for the outsert (odds ratio (OR) 1.01, 95% confidence interval (CI) 0.98 to 1.04) or the insert (OR 0.99, 95% CI 0.96 to 1.02). Percent of intensification in the four arms was similar (approximately 46%). Adjustment for physician characteristics (e.g., age, sex, practice location) had no impact on these findings.ConclusionsPEMs have no effect on physician’s adherence to recommendations for the management of diabetes-related complications in Ontario. Further research should investigate the effect of other strategies to narrow this evidence-to-practice gap.Trial registrationISRCTN72772651. Retrospectively registered 21 July 2005.

Association of neighbourhood-level poverty with outcomes and clinical care following atrial fibrillation diagnosis in a universal healthcare system

Abstract Background There are limited data on the association of poverty with outcomes and care patterns after an atrial fibrillation (AF) diagnosis in jurisdictions with universal healthcare. The Canadian province of Ontario provides publicly funded healthcare and prohibits private payment for medically necessary physician and in-hospital care. It also covers prescription medications for residents aged &amp;gt;65 years. Purpose Determine the association of neighbourhood-level poverty with outcomes and processes of care after AF diagnosis in older people within a universal healthcare system. Methods Using linked administrative databases, we conducted a population-based cohort study of community-dwelling adults aged ≥66 years who were newly diagnosed with AF in Ontario between April 1, 2007 and March 31, 2019. The primary exposure was material deprivation of patients' neighborhood of residence. This metric is derived using Canadian census data to estimate inability to access and attain basic material needs. Neighborhoods were categorized by quintile of material deprivation from Q1 (wealthiest) to Q5 (poorest). We used cause-specific hazards regression models to study the association of deprivation quintile with time to the following outcomes over one year from AF diagnosis: death, ischemic stroke, bleeding, heart failure (HF) hospitalization, cardiology services, and AF-specific treatments. Models accounted for clustering by region of residence and adjusted for age, sex, diabetes, HF, stroke/transient ischemic attack, vascular disease, hypertension, bleeding history, rural residence, renal function, and setting of AF diagnosis (hospital, emergency department [ED] or outpatient). Results We studied 350,353 patients with AF (median age 78 years, 48.9% female). People from neighborhoods in higher deprivation quintiles (poorer) were more likely to be diagnosed in hospital/ED than outpatient settings. Relative to people from the wealthiest neighbourhoods (Q1), patients in the poorest neighbourhoods (Q5) had higher prevalence of baseline hypertension, diabetes, HF, vascular disease and other comorbidities. In adjusted analyses (Figure), higher quintiles of neighborhood poverty were associated with greater rates of death, ischemic stroke, bleeding, and HF hospitalization, but lower rates of cardiology visits, cardiac testing, anticoagulation, anti-arrhythmic medications, cardioversion, or AF ablation. Conclusions In a setting of universal healthcare and prescription medication coverage, people living in poorer neighbourhoods had worse baseline health and higher rates of adverse outcomes after an AF diagnosis. Despite this, people in poorer neighbourhoods had less cardiology visits and diagnostic tests and were less likely to receive anticoagulation and rhythm control interventions. This shows that universal healthcare and medication coverage are insufficient to achieve equitable health care and outcomes for people with AF. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): This research was funded by a Canadian Institutes of Health Research Foundation grant; and is supported by ICES (formerly the Institute for Clinical Evaluative Sciences), which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC).

Opioid use after outpatient elective general surgery: quantifying the burden of persistent use.

Surgery is a major risk factor for chronic opioid use among patients who had not recently been prescribed opioids. This study identifies the rate of, and risk factors for, persistent opioid use following laparoscopic cholecystectomy and open inguinal hernia repair in patients not recently prescribed opioids. This retrospective population-based cohort study included all patients who had not been prescribed opioids in the 6 months prior to undergoing open inguinal hernia repair or laparoscopic cholecystectomy from January 2013 to July 2016 in Ontario. Opioid prescription was identified from the provincial Narcotics Monitoring System and data were obtained from the Institute for Clinical Evaluative Sciences. The primary outcome was persistent opioid use after surgery (3, 6, 9 and 12 months). Associated risk factors and prescribing patterns were also examined. Among the 90,326 patients in the study cohort, 80% filled an opioid prescription after surgery, with 11%, 9%, 5% and 1% filling a prescription at 3, 6, 9 and 12 months, respectively. Significant variability was identified in the type of opioid prescribed (41% codeine, 31% oxycodone, 18% tramadol) and in regional prescribing patterns (mean prescription/region range, 135-225 oral morphine equivalents). Predictors of continued opioid use included age, female gender, lower income quintile and being operated on by less experienced surgeons. Most patients who undergo elective cholecystectomy and hernia repair will fill a prescription for an opioid after surgery, and many will continue to fill opioid prescriptions for considerably longer than clinically anticipated. There is important variability in opioid type, regional prescribing patterns and risk factors that identify strategic targets to reduce the opioid burden in this patient population.

Periodic Colonoscopies Are Associated with Improved Survival and Prognosis of Colorectal Cancer in Ulcerative Colitis.

This study aimed to identify whether ulcerative colitis (UC) patients who develop colorectal cancer (CRC) present at earlier stages of CRC and have improved survival if prior to their CRC diagnosis, they underwent intermittent follow-up colonoscopies compared to those who have no follow-up colonoscopies. Patients with UC who developed primary CRC were identified using data provided by the Institute for Clinical Evaluative Sciences. We defined low-risk CRC stage as estimated 5-year survival ≥ 80% compared to high-risk CRC as 5-year survival < 80%. A total of 421 patients were identified with UC and CRC. The 15-year mortality rate was significantly higher in those who did not have follow-up colonoscopy (33/74; 44.6%) compared to the follow-up group (105/347; 30.3%) (p = 0.0172). Among the 219 patients with UC with staging information available, patients who did not have follow-up colonoscopy were more likely to present with high-risk CRC (24/31; 77.4%) compared with patients who had follow-up colonoscopies (88/188; 44.4%) (p = 0.0016). Those who underwent follow-up colonoscopies at average intervals ≤ 3years presented with high-risk CRC 41.3% of the time, which was less than the 48.6% in those with less frequent colonoscopies and 77.4% in those with no follow-up (p = 0.0048). Patients with UC who underwent intermittent follow-up colonoscopies had CRC detected at earlier stages and improvement in all-cause mortality, compared to those who with no follow-up colonoscopies. This may support regular surveillance colonoscopies for patients with UC.

Radiation oncologist consultations prior to prostatectomy in Ontario, Canada: Disparities and opportunities.

e17052 Background: Men with localized prostate cancer have many options for initial definitive treatment. In 2015, Cancer Care Ontario Quality Based Procedures (QBP) recommended that men undergoing radical prostatectomy (RP) in Ontario be seen by a radiation oncologist (RO) or discussed at a multidisciplinary case conference (MCC) prior to surgery. An a-priori target rate of 76% was set by QBP, but to our knowledge, has not been reported upon to date. Our objective was to use population-based data to explore factors associated with not receiving RO consult/MCC prior to RP. Methods: Men with localized prostate cancer diagnosed and treated in Ontario, Canada with RP between 2007 and 2017 were identified using administrative data from the Institute for Clinical Evaluative Sciences. Physician billing data was utilized to identify patients who received RO consult/MCC prior to RP. Trends were evaluated using the Cochran-Armitage test. Multivariable logistic regression was used to identify patient and provider factors predictive of RO/MCC prior to RP. Results: 31,467 men with localized prostate cancer underwent RP between 2007 and 2017. Prior to RP, 29.3% of men were seen by RO, 1.0% underwent MCC, and 1.6% had both. RO consult/MCC prior to RP increased from 18.0% in 2007 to 47.8% in 2017 ( p&lt;0.001). On multivariable analysis, the Odds Ratio (OR) of RO consult/MCC prior to RP between the lowest and highest geographic regions (LHINs) was 8.79 (95% CI 6.83–11.32, p&lt;0.001). RO consult/MCC was less likely to occur for patients living further from the nearest cancer center (OR 0.74 per 50km, 95% CI 0.70–0.77, p&lt;0.001) and more likely to occur for men residing in the highest versus lowest income quintile regions (OR 1.42, 95% CI 1.30–1.55, p&lt;0.001). Men with NCCN Low (OR 1.31, 95% CI 1.16–1.47, p&lt;0.001), High (OR 1.20, 95% CI 1.09–1.31, p&lt;0.001) or Very High (OR 1.24, 95% CI 1.11–1.30, p&lt;0.001) risk disease were more likely to receive RO consult/MCC compared to those with favourable-intermediate risk disease. Of the 128 urologists who performed at least 10 RP between 2016 and 2017, RO referral/MCC rate ranged from 0% to 100%, with 31 urologists (24.2%) having ≥76% of their patients seen prior to RP. To meet QBP targets in 2017, an additional 701 men would have needed RO consult/MCC. If all were seen by RO, approximately 2.4 additional full time equivalent RO positions would be needed. Conclusions: Despite increasing rates of utilization, a large proportion of men are not seen by RO or MCC prior to RP in Ontario, Canada. While the largest factors predicting RO consult/MCC discussion appear to be geographic and which urologist performs the RP, these factors are closely intertwined. In addition, these factors may be related to RO availability and radiation system capacity, which would need to be addressed to meet patient demand should QBP consultation rates be mandated to reduce disparities in pre-RP consultation practices.

All-Cause and Cancer-Specific Death of Older Adults Following Surgery for Cancer

Cancer care has inherent complexities in older adults, including balancing risks of cancer and noncancer death. A poor understanding of cause-specific outcomes may lead to overtreatment and undertreatment. To examine all-cause and cancer-specific death throughout 5 years for older adults after cancer resection. This population-based cohort study was conducted in Ontario, Canada, using the administrative databases stored at ICES (formerly the Institute for Clinical Evaluative Sciences). All adults 70 years or older who underwent resection for a new diagnosis of cancer between January 1, 2007, and December 31, 2017, were included. Patients were followed up until death or censored at date of last contact of December 31, 2018. Cancer resection. Using a competing risks approach, the cumulative incidence of cancer and noncancer death was estimated and stratified by important prognostic factors. Multivariable subdistribution hazard models were fit to explore prognostic factors. Of 82 037 older adults who underwent surgery (all older than 70 years; 52 119 [63.5%] female), 16 900 of 34 044 deaths (49.6%) were cancer related at a median (interquartile range) follow-up of 46 (23-80) months. At 5 years, estimated cumulative incidence of cancer death (20.7%; 95% CI, 20.4%-21.0%) exceeded noncancer death (16.5%; 95% CI, 16.2%-16.8%) among all patients. However, noncancer deaths exceeded cancer deaths starting at 3 years after surgery in breast, prostate, and melanoma skin cancers, patients older than 85 years, and those with frailty. Cancer type, advancing age, and frailty were independently associated with cause-specific death. At the population level, the relative burden of cancer deaths exceeds noncancer deaths for older adults selected for surgery. No subgroup had a higher burden of noncancer death early after surgery, even in more vulnerable patients. This cause-specific overall prognosis information should be used for patient counseling, to assess patterns of over- or undertreatment in older adults with cancer at the system level, and to guide targets for system-level improvements to refine selection criteria and perioperative care pathways for older adults with cancer.

Stress Incontinence Surgery Does Not Cause Pelvic Malignancy: A Population-Based Cohort Study

We sought to determine if stress urinary incontinence surgery (mesh or nonmesh) is associated with the development of pelvic malignancies later in life. We performed a retrospective cohort study between January 1, 2002 and October 31, 2015 of all women in Ontario, Canada without a history of pelvic malignancy who underwent an index stress incontinence surgery. The primary outcome was a composite of any pelvic malignancy (including urological and gynecological cancers) following stress incontinence surgery. Secondarily, we considered each cancer individually. A survival analysis using a Cox proportional-hazards model with a 3-level categorical exposure (mesh surgery, nonmesh surgery, and control) was performed. Patients were followed until death, emigration or the study end (October 31, 2017). Of the women 74,968 underwent stress urinary incontinence surgery during the study period. There were 5,505,576 women in the control group. Over a median followup of 8.5 years (IQR, 5.5-11.9), 587 pelvic malignancies occurred in the surgery group. Women who underwent stress incontinence surgery had a reduced risk of pelvic malignancy independent of surgery type, compared to controls (Wald type 3 p <0.001; mesh HR, 0.68 [95% CI, 0.62-0.76]; p <0.0001; nonmesh HR, 0.37 [95% CI, 0.29-0.46]; p <0.0001). The individual pelvic cancers similarly demonstrated a reduced risk of malignancy following stress incontinence surgery. At a median followup of 8.5 years, women had no increased risk of pelvic malignancy following either mesh or nonmesh stress urinary incontinence surgery in a large population-based cohort.

The impact of routine HIV drug resistance testing in Ontario: A controlled interrupted time series study.

BackgroundKnowledge of HIV drug resistance informs the choice of regimens and ensures that the most efficacious options are selected. In January 2014, a policy change to routine resistance testing was implemented in Ontario, Canada. The objective of this study was to investigate the policy change impact of routine resistance testing in people with HIV in Ontario, Canada since January 2014.MethodsWe used data on people with HIV living in Ontario from administrative databases of the Institute for Clinical Evaluative Sciences (ICES) and Public Health Ontario (PHO), and ran ordinary least squares (OLS) models of interrupted time series to measure the levels and trends of 2-year mortality, 2-year hospitalizations and 2-year emergency department visits before (2005–2013) and after the policy change (2014–2017). Outcomes were collected in biannual periods, generating 18 periods before the intervention and 8 periods after. We included a control series of people who did not receive a resistance test within 3 months of HIV diagnosis.ResultsData included 12,996 people with HIV, of which 8881 (68.3%) were diagnosed between 2005 and 2013, and 4115 (31.7%) were diagnosed between 2014 and 2017. Policy change to routine resistance testing within 3 months of HIV diagnosis led to a decreasing trend in 2-year mortality of 0.8% every six months compared to the control group. No significant differences in hospitalizations or emergency department visits were noted.InterpretationThe policy of routine resistance testing within three months of diagnosis is beneficial at the population level.

Determinants of asthma-related emergency department return visits in adults: A population-based study

RATIONALE: Emergency department (ED) return-visit rates provide a measure of the quality of acute asthma care. OBJECTIVES: We sought to assess the impact of patient and site characteristics, including asthma management strategies, on return visits within 72 hours, prior to implementation of a standardized adult ED asthma care pathway in EDs throughout Ontario, Canada. METHODS: This population-based cohort study utilized comprehensive administrative health data from the Institute for Clinical Evaluative Sciences for adults 20 to 64 years old who had at least one ED visit for asthma from April 1, 2006 to March 31, 2008. Detailed information on ED management strategies was available on a subset of 37 sites whose staff attended pathway implementation workshops. MEASUREMENTS AND MAIN RESULTS: A total of 41,140 asthma visits to 167 EDs were analyzed. Most patients (64.8%) were triaged as high acuity and the majority (92.8%) were discharged. The return-visit rate was 2.8%. Female gender, younger age, higher acuity, leaving the ED before visit completion and prior admission or ED visit for asthma were associated with increased odds of a return visit. The only management strategy associated with reduced ED visits was access to 24-hour peak flow measurement. CONCLUSION: This study identified well-recognized patient- and hospital-level risk factors for return ED visits. Access to peak flow monitoring was the only protective management strategy found. As many ED asthma service and care gaps exist, province-wide implementation of a standardized care pathway may greatly impact ED management and improve patient outcomes including return ED visits.

Effects of removing a fee-for-service incentive on specialist chronic disease services: a time-series analysis.

Physician payment models are known to affect the nature and volume of services provided. Our objective was to study the effects of removing a financial incentive, the fee-for-service premium, on the provision of chronic disease follow-up services by internal medicine, cardiology, nephrology and gastroenterology specialists. We collected linked administrative health care data for the period 1 April 2013 to 31 March 2017 from databases held at the Institute for Clinical Evaluative Sciences (ICES) in Ontario, Canada. We conducted a time-series analysis before and after the removal of the fee-for-service premium on 1 April 2015. The primary outcome was total monthly visits for chronic disease follow-up services. Secondary outcomes were monthly visits for total follow-up services and new patient consultations. We compared internal medicine, cardiology, nephrology and gastroenterology specialists practising during the study timeframe with respirology, hematology, endocrinology, rheumatology and infectious diseases specialists who remained eligible to claim the premium. We chose this comparison group as these are all subspecialties of internal medicine, providing similar services. The number of chronic disease follow-up visits decreased significantly after removal of the premium, but there was no decrease in total follow-up visits. There was also a significant downward trend in new patient consultations. No changes were observed in the comparison group. The decrease in volume of chronic disease follow-up visits can be explained by diagnostic criteria being met less often, rather than an actual reduction in services provided. Potential effects on patient outcomes require further exploration.

Symposium: Distributed Networks of Federated Secure Research Data Environments – Enabling Analytics Across Multiple Platforms

IntroductionUsers of linked data require access to an increasing number of heterogeneous datasets from diverse domains, often held in different secure research data environments, especially for multi-jurisdictional projects. Under the traditional model of data access, projects are required to transfer and harmonise the necessary datasets in one central location before analysis can be undertaken, increasing the time required for data acquisition and preparation.&#x0D; Objectives and ApproachIn a federated data environment, analysts query distributed datasets held in a network of multiple secure data environments via a central virtual database, without requiring the data to move. Instead, the data is analysed as close as possible to its storage location, minimising the amount of data transfers and giving data custodians more control over their data.&#x0D; This symposium explores the challenges and opportunities of establishing and operating a distributed network of federated secure research data environments. Leading organisations operating data platforms in various jurisdictions present for 15 minutes each the current capabilities of their platforms, the landscape of data environments in their jurisdictions and potential approaches to key questions such as:&#x0D; &#x0D; Harmonising/federating data sources&#x0D; Data security&#x0D; Data governance&#x0D; Discoverability/metadata&#x0D; Performance&#x0D; &#x0D; The audience is the then invited to participate in discussing the topic for the remaining 30 minutes.&#x0D; The following individuals have been approached to represent their organisations in this symposium:&#x0D; &#x0D; Professor David Ford, Swansea University: UK Secure eResearch Platform (UK SErP)&#x0D; Charles Victor, Institute for Clinical Evaluative Sciences (ICES): ICES Data &amp; Analytic Virtual Environment (IDAVE)&#x0D; Professor Louisa Jorm, Centre for Big Data Research in Health, University of New South Wales: E-Research Institutional Cloud Architecture (ERICA)&#x0D; Professor Kimberlyn McGrail, Population Data BC: Secure Research Environment (SRE)&#x0D; &#x0D; Results / Conclusion / ImplicationsThis symposium will help formulate requirements for and barriers to distributed networks of federated secure research data environments, and create a foundation for data analytics across multiple platforms.

Using A Privacy Preserving Record Linkage to Facilitate an Ongoing Crosswalk Between Research and Health Administrative Databases

IntroductionThe Ontario Brain Institute has developed Brain-CODE, an informatics platform designed to support the collection, storage, federation, sharing and analysis of different neuroscience research data types across several brain disorders. Linking such “deep” research data with “broad” health administrative data allows for improved characterization of disorders and supports the development of related health and social policies (Anderson et al., 2015). A privacy preserving record linkage protocol, developed through the Indoc Consortium, has been used to facilitate such linkages between Brain-CODE and administrative data holdings at the Institute for Clinical Evaluative Sciences (ICES; e.g., emergency department use, inpatient records, prescription drug utilization) (Gee et al., 2018).&#x0D; Objectives and ApproachThree linkage pilots in the areas of neurodevelopmental disorders, epilepsy, and stroke research have been completed with &gt;99% success match rates across all projects. However, each of these projects required a significant amount of human and computational resources to complete. With other similar data linkages being planned, it was determined that a more permanent solution was required rather than completing linkages on a project-by-project basis. The governance and technical elements to support the creation and maintenance of such a crosswalk between Brain-CODE and ICES were reviewed with an implementation plan subsequently developed.&#x0D; Results:A methodology for creating a crosswalk between Brain-CODE and ICES has been established. The same privacy preserving record linkage protocol, as used in the previous linkage pilots, will support the creation of this crosswalk. A plan has been established to update this crosswalk annually to account for new study participants on Brain-CODE.&#x0D; Conclusion / ImplicationsThe creation of this crosswalk will allow for a more streamlined approach of data linkage between Brain-CODE and ICES. Such an approach can significantly reduce overall resourcing requirements, enable more efficient data linkages, and contribute to the coupling of “broad” and “deep” data.

Effects of Rurality and Geographical Distance on Unplanned Emergency Department Utilization for Children With Asthma: A Population Level Retrospective Cohort Study.

Asthma is a highly prevalent chronic disease among Ontario children; however, the extent to which rural status and distance are associated with unplanned emergency department (ED) use by this population is largely unknown. To explore the impact of rurality and geographical distance to primary and specialist care services on healthcare utilization by analyzing the use of unplanned ED services. A population level retrospective cohort study of Ontario children ages 5-14 with newly diagnosed asthma was conducted using health administrative data from Institute for Clinical Evaluative Sciences (ICES). Adjusted logistic regression models were used to analyze the association between unplanned ED use with rural status and distance to general practitioner/family physician (GP/FP) and specialist healthcare services, while controlling for confounders. In total, 19,732 individuals met the inclusion criteria. Individuals who lived in rural locations (OR 2.00, 95% CI 1.64-2.44) and travelled >50 km to a GP/FP (OR 1.25, 95% CI 1.06-1.48) or specialist (OR 1.20, 95% CI 1.05-1.38) were more likely to utilize an ED. Children with asthma utilize healthcare services differently based on rural status and distance to services. To ensure equitable access to care, there is a need to accommodate for these factors in the planning and provision of asthma healthcare services.

Hospitalization Outcomes of Delirium in Patients Admitted to Acute Care Hospitals in Their Last Year of Life: A Population-Based Retrospective Cohort Study

ContextDelirium is a highly distressing neurocognitive disorder for patients at the end of life. ObjectivesTo compare hospitalization outcomes between patients with and without delirium admitted to acute care hospitals in the last year of life. MethodsUsing linked administrative data from ICES (previously known as the Institute for Clinical Evaluative Sciences), this population-based retrospective cohort study included adults who died in Ontario between January 1, 2014 and December 31, 2016 and were admitted to an acute care hospital in their last year of life. Delirium was identified via diagnosis codes on the hospitalization discharge record. Outcomes included lengths of stay, discharge location, and in-hospital mortality. We used multivariable generalized estimating equations to compare outcomes between patients with and without delirium. ResultsOf 208,715 decedents, 9.3% experienced delirium in at least one hospitalization in the last year of life. The mean hospitalization lengths of stay was 13.8 days in patients with delirium (SD = 21.1) or 1.80 times longer (95% CI = 1.75–1.84) compared with those without delirium. Among patients discharged alive, patients with delirium were 1.32 times (95% CI = 1.27–1.38) more likely to be discharged to another institution rather than discharged home. There was no difference in in-hospital mortality between patients with and without delirium (relative risk = 1.01; 95% CI = 0.98–1.05). ConclusionIn the last year of life, hospitalized patients with recorded delirium experience poorer outcomes, including longer lengths of stay and increased risk of postdischarge institution use, compared with those without delirium. These outcomes illustrate added burden for patients, their families, and the health care system, thus highlighting the need for delirium prevention and early detection in addition to informed transitional care decisions.