ICES: Data, Discovery, Better Health

High-cost users after sepsis: a population-based observational cohort study

BACKGROUND

High-cost users (HCU) represent important targets for health policy interventions. Sepsis is a life-threatening syndrome that is associated with high morbidity, mortality, and economic costs to the healthcare system. We sought to estimate the effect of sepsis on being a subsequent HCU.

METHODS

Using linked health-administrative databases, we conducted a population-based, propensity score-weighted cohort study of adults who survived a hospitalization in Ontario, Canada between January 2016 and December 2017. Sepsis was identified using a validated algorithm. The primary outcome was being a persistent HCU after hospital discharge (in the top 5% or 1% of total health care spending for 90 consecutive days), and the proportion of follow-up time since discharge as a HCU.

RESULTS

We identified 927,057 hospitalized individuals, of whom 79,065 had sepsis. Individuals who had sepsis were more likely to be a top 5% HCU for 90 consecutive days at any time after discharge compared to those without sepsis (OR 2.24; 95% confidence interval [CI] 2.04-2.46) and spent on average 42.3% of their follow up time as a top 5% HCU compared to 28.9% of time among those without sepsis (RR 1.46; 95% CI 1.45-1.48). Individuals with sepsis were more likely to be a top 1% HCU for 90 consecutive days compared to those without sepsis (10% versus 5.1%, OR 2.05 [95% CI 1.99-2.11]), and spent more time as a top 1% HCU (18.5% of time versus 10.8% of time, RR 1.68 [95% CI 1.65-1.70]).

CONCLUSIONS

The sequelae of sepsis result in higher healthcare costs with important economic implications. After discharge, individuals who experienced sepsis are more likely to be a HCU and spend more time as a HCU compared to individuals who did not experience sepsis during hospitalization.

Healthcare visits for new neurodevelopmental problems before and during the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic disrupted healthcare delivery. We hypothesized that children with neurodevelopmental problems would have reduced healthcare utilization during the pandemic compared to before the pandemic.

METHODS

We conducted a population-based study of healthcare visits for new neurodevelopmental problems among children ages 0-6 years in Ontario, Canada. Our outcome measure was rate per 1000 children-months for healthcare visits for new neurodevelopmental problems. We compared changes in monthly rates before and during the pandemic using interrupted time series analysis (ITSA).

RESULTS

The rate of new neurodevelopmental problems before the pandemic was 6.31 per 1000 children-months and during the pandemic was 6.58 per 1000 children-months. However, using ITSA, there were no differences in monthly rates of healthcare visits for new neurodevelopmental problems before and during the pandemic. The observed rate during the first 30 days of the pandemic dropped to 3.40 per 1000 children-months.

CONCLUSION

We found no significant difference in rates of healthcare visits for new neurodevelopmental problems before and during the pandemic. There was a decrease in the number of visits during the first 30 days of the pandemic compared to all months prior.

IMPACT

This study found no significant difference in rates of healthcare visits for new neurodevelopmental problems before and during the pandemic. There was a decrease in the number of visits during the first 30 days of the pandemic compared to all months prior. This study adds information on healthcare access for children during the COVID-19 pandemic. The rapid deployment of virtual healthcare delivery in Ontario, Canada may explain the fast recovery of healthcare utilization for children with neurodevelopmental problems.

Impact of structured multicentre enhanced recovery after surgery (ERAS) protocol implementation on length of stay after colorectal surgery

BACKGROUND

Increased length of stay after surgery is associated with increased healthcare utilization and adverse patient outcomes. While enhanced recovery after surgery (ERAS) protocols have been shown to reduce length of stay after colorectal surgery in trial settings, their effectiveness in real-world settings is more uncertain. The aim of this study was to assess the impact of ERAS protocol implementation on length of stay after colorectal surgery, using real-world data.

METHODS

In 2012, ERAS protocols were introduced at 15 Ontario hospitals as part of the iERAS study. A cohort of patients undergoing colorectal surgery treated at these hospitals between 2008 and 2019 was created using health administrative data. Mean length of stay was computed for the intervals before and after ERAS implementation. Interrupted time series analyses were performed for predefined subgroups, namely all colorectal surgery, colorectal surgery without complications, right-sided colorectal surgery, and left-sided colorectal surgery. Sensitivity analyses were then conducted using adjusted length of stay, accounting for length of stay predictors, including: patient age, sex, marginalization, co-morbidities, and diagnosis; surgeon volume of cases, years in practice, and colorectal surgery expertise; hospital volume; and other contextual factors, including procedure type and timing, surgical approach, and in-hospital complications.

RESULTS

A total of 32 612 patients underwent colorectal surgery during the study interval. ERAS implementation led to a decrease in length of stay of 1.05 days (13.7%). Larger decreases in length of stay were seen with more complex surgeries, with a level change of 1.17 days (15.6%) noted for the subgroup of patients undergoing left-sided colorectal surgery. The observed decreases in length of stay were durable for the length of the study interval in all analyses. When adjusting for predictors of length of stay, the effect of ERAS implementation on length of stay was larger (reduction of 1.46 days).

CONCLUSION

Introducing formal ERAS protocols reduces length of stay after colorectal surgery significantly, independent of temporal trends toward decreasing length of stay. These effects are durable, demonstrating that ERAS protocol implementation is an effective hospital-level intervention to reduce length of stay after colorectal surgery.

Association Between Surgeon Sex and Days Alive at Home Following Surgery: A Population-Based Cohort Study

Objective

The objective of this study was to measure potential associations between surgeon sex and number of days alive and at home (DAH).

Background

Patients treated by female surgeons appear to have lower rates of mortality, complications, readmissions, and healthcare costs when compared with male surgeons. DAH is a validated measure, shown to better capture the patient experience of postoperative recovery.

Methods

We conducted a retrospective study of adults (≥18 years of age) undergoing common surgeries between January 01, 2007 and December 31, 2019 in Ontario, Canada. The outcome measures were the number of DAH within 30-, 90-, and 365-days. The data was summarized using descriptive statistics and adjusted using multivariable generalized estimating equations.

Results

During the study period, 1,165,711 individuals were included, of which 61.9% (N = 721,575) were female. Those managed by a female surgeon experienced a higher mean number of DAH when compared with male surgeons at 365 days (351.7 vs. 342.1 days; P < 0.001) and at each earlier time point. This remained consistent following adjustment for covariates, with patients of female surgeons experiencing a higher number of DAH at all time points, including at 365 days (343.2 [339.5-347.1] vs. 339.4 [335.9-343.0] days). Multivariable regression modeling revealed that patients of male surgeons had a significantly lower number of DAH versus female surgeons.

Conclusions

Patients of female surgeons experienced a higher number of DAH when compared with those treated by male surgeons at all time points. More time spent at home after surgery may in turn lower costs of care, resource utilization, and potentially improve quality of life. Further studies are needed to examine these findings across other care contexts.

Federal opioid agonist therapy policy: interrupted time series analysis of the impact of the methadone exemption removal across eight provinces in Canada

BACKGROUND

Federal deregulation of opioid agonist therapies are an attractive policy option to improve access to opioid use disorder care and achieve widespread beneficial impacts on growing opioid-related harms. There have been few evaluations of such policy interventions and understanding effects can help policy planning across jurisdictions.

METHODS

Using health administrative data from eight of ten Canadian provinces, this study evaluated the impacts of Health Canada's decision in May 2018 to rescind the requirement for Canadian health professionals to obtain an exemption from the Canadian Drugs and Substance Act to prescribe methadone for opioid use disorder. Over the study period of June 2017 to May 2019, we used descriptive statistics to capture overall trends in the number of agonist therapy prescribers across provinces and we used interrupted time series analysis to determine the effect of this decision on the trajectories of the agonist therapy prescribing workforces.

RESULTS

There were important baseline differences in the numbers of agonist therapy prescribers. The province with the highest concentration of prescribers had 7.5 more prescribers per 100,000 residents compared to the province with the lowest. All provinces showed encouraging growth in the number of prescribers through the study period, though the fastest growing province grew 4.5 times more than the slowest. Interrupted time series analyses demonstrated a range of effects of the federal policy intervention on the provinces, from clearly positive changes to possibly negative effects.

CONCLUSIONS

Federal drug regulation policy change interacted in complex ways with provincial health professional regulation and healthcare delivery, kaleidoscoping the effects of federal policy intervention. For Canada and other health systems such as the US, federal policy must account for significant subnational variation in OUD epidemiology and drug regulation to maximize intended beneficial effects and mitigate the risks of negative effects.

Impact of COVID-19 pandemic on prescription stimulant use among children and youth: a population-based study

COVID-19 associated public health measures and school closures exacerbated symptoms in some children and youth with attention-deficit hyperactivity disorder (ADHD). Less well understood is how the pandemic influenced patterns of prescription stimulant use. We conducted a population-based study of stimulant dispensing to children and youth ≤ 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 the dispensing of stimulants occurred. We used interrupted time series models to quantify changes in dispensing following the structural break and compare observed and expected stimulant use. Our main outcome was the change in the monthly rate of stimulant use per 100,000 children and youth. Following an initial immediate decline of 60.1 individuals per 100,000 (95% confidence interval [CI] - 99.0 to - 21.2), the monthly rate of stimulant dispensing increased by 11.8 individuals per 100,000 (95% CI 10.0-13.6), with the greatest increases in trend observed among females, individuals in the highest income neighbourhoods, and those aged 20 to 24. Observed rates were between 3.9% (95% CI 1.7-6.2%) and 36.9% (95% CI 34.3-39.5%) higher than predicted among females from June 2020 onward and between 7.1% (95% CI 4.2-10.0%) and 50.7% (95% CI 47.0-54.4%) higher than expected among individuals aged 20-24 from May 2020 onward. Additional research is needed to ascertain the appropriateness of stimulant use and to develop strategies supporting children and youth with ADHD during future periods of long-term stressors.

Uptake of COVID-19 vaccination among community-dwelling individuals receiving healthcare for substance use disorder and major mental illness: a matched retrospective cohort study

Introduction

Patients with major mental illness (MMI) and substance use disorders (SUD) face barriers in accessing healthcare. In this population-based retrospective cohort study, we investigated the uptake of COVID-19 vaccination in Ontario, Canada among community-dwelling individuals receiving healthcare for major mental illness (MMI) and/or substance use disorders (SUD), comparing them to matched general population controls.

Methods

Using linked health administrative data, we identified 337,290 individuals receiving healthcare for MMI and/or SUD as of 14 December 2020, matched by age, sex, and residential geography to controls without such healthcare. Follow-up extended until 31 December 2022 to document vaccination events.

Results

Overall, individuals receiving healthcare for MMI and/or SUD (N = 337,290) had a slightly lower uptake of first (cumulative incidence 82.45% vs. 86.44%; hazard ratio [HR] 0.83 [95% CI 0.82-0.83]) and second dose (78.82% vs. 84.93%; HR 0.77 [95% CI 0.77-0.78]) compared to matched controls. Individuals receiving healthcare for MMI only (n = 146,399) had a similar uptake of first (87.96% vs. 87.59%; HR 0.97 [95% CI 0.96-0.98]) and second dose (86.09% vs. 86.05%, HR 0.94 [95% CI 0.93-0.95]). By contrast, individuals receiving healthcare for SUD only (n = 156,785) or MMI and SUD (n = 34,106) had significantly lower uptake of the first (SUD 78.14% vs. 85.74%; HR 0.73 [95% CI 0.72-0.73]; MMI & SUD 78.43% vs. 84.74%; HR 0.76 [95% CI 0.75-0.77]) and second doses (SUD 73.12% vs. 84.17%; HR 0.66 [95% CI 0.65-0.66]; MMI & SUD 73.48% vs. 82.93%; HR 0.68 [95% CI 0.67-0.69]).

Discussion

These findings suggest that effective strategies to increase vaccination uptake for future COVID-19 and other emerging infectious diseases among community-dwelling people with SUD are needed.

Methodological guidance for the use of real-world data to measure exposure and utilization patterns of osteoporosis medications

Observational studies of osteoporosis medications can provide critical real-world evidence (RWE) that fills knowledge gaps left by clinical trials. However, careful consideration of study design is needed to yield reliable estimates of association. In particular, obtaining valid measurements of exposure to osteoporosis medications from real-world data (RWD) sources is complicated due to different medication classes, formulations, and routes of administration, each with different pharmacology. Extended half-lives of bisphosphonates and extended dosing of denosumab and zoledronic acid require particular attention. In addition, prescribing patterns and medication taking behavior often result in gaps in therapy, switching, and concomitant use of osteoporosis therapies. In this review, we present important considerations and provide specialized guidance for measuring osteoporosis drug exposures in RWD. First, we compare different sources of RWD used for osteoporosis drug studies and provide guidance on identifying osteoporosis medication use in these data sources. Next, we provide an overview of osteoporosis pharmacology and how it can influence decisions on exposure measurement within RWD. Finally, we present considerations for the measurement of osteoporosis medication exposure, adherence, switching, long-term exposures, and drug holidays using RWD. Ultimately, a thorough understanding of the differences in RWD sources and the pharmacology of osteoporosis medications is essential to obtain valid estimates of the relationship between osteoporosis medications and outcomes, such as fractures, but also to improve the critical appraisal of published studies.

Sex-Based Analysis of Quality Indicators of End-of-Life Care in Gastrointestinal Malignancies

Indices of aggressive or supportive end-of-life (EOL) care are used to evaluate health services quality. Disparities according to sex were previously described, with studies showing that male sex is associated with aggressive EOL care. This is a secondary analysis of 69,983 patients who died of a GI malignancy in Ontario between 2006 and 2018. Quality indices from the last 14-30 days of life and aggregate measures for aggressive and supportive EOL care were derived from administrative data. Hospitalizations, emergency department use, intensive care unit admissions, and receipt of chemotherapy were considered indices of aggressive care, while physician house call and palliative home care were considered indices of supportive care. Overall, a smaller proportion of females experienced aggressive care at EOL (14.3% vs. 19.0%, standardized difference = 0.13, where ≥0.1 is a meaningful difference). Over time, rates of aggressive care were stable, while rates of supportive care increased for both sexes. Logistic regression showed that younger females (ages 18-39) had increased odds of experiencing aggressive EOL care (OR 1.71, 95% CI 1.30-2.25), but there was no such association for males. Quality of EOL care varies according to sex, with a smaller proportion of females experiencing aggressive EOL care.

Contemporary trends in the incidence and timing of spinal metastases: A population-based study

Background

Spinal metastases are a significant complication of advanced cancer. In this study, we assess temporal trends in the incidence and timing of spinal metastases and examine underlying patient demographics and primary cancer associations.

Methods

In this population-based retrospective cohort study, health data from 2007 to 2019 in Ontario, Canada were analyzed (n = 37, 375 patients identified with spine metastases). Primary outcomes were annual incidence of spinal metastasis, and time to metastasis after primary diagnosis.

Results

The age-standardized incidence of spinal metastases increased from 229 to 302 cases per million over the 13-year study period. The average annual percent change (AAPC) in incidence was 2.2% (95% CI: 1.4% to 3.0%) with patients aged ≥85 years demonstrating the largest increase (AAPC 5.2%; 95% CI: 2.3% to 8.3%). Lung cancer had the greatest annual incidence, while prostate cancer had the greatest increase in annual incidence (AAPC 6.5; 95% CI: 4.1% to 9.0%). Lung cancer patients were found to have the highest risk of spine metastasis with 10.3% (95% CI: 10.1% to 10.5%) of patients being diagnosed at 10 years. Gastrointestinal cancer patients were found to have the lowest risk of spine metastasis with 1.0% (95% CI: 0.9% to 1.0%) of patients being diagnosed at 10 years.

Conclusions

The incidence of spinal metastases has increased in recent years, particularly among older patients. The incidence and timing vary substantially among different primary cancer types. These findings contribute to the understanding of disease trends and emphasize a growing population of patients who require subspecialty care.

Association of neighbourhood-level material deprivation with adverse outcomes and processes of care among patients with heart failure in a single-payer healthcare system: A population-based cohort study

AIM

We studied the association between neighbourhood material deprivation, a metric estimating inability to attain basic material needs, with outcomes and processes of care among incident heart failure patients in a universal healthcare system.

METHODS AND RESULTS

In a population-based retrospective study (2007-2019), we examined the association of material deprivation with 1-year all-cause mortality, cause-specific hospitalization, and 90-day processes of care. Using cause-specific hazards regression, we quantified the relative rate of events after multiple covariate adjustment, stratifying by age ≤65 or ≥66 years. Among 395 763 patients (median age 76 [interquartile range 66-84] years, 47% women), there was significant interaction between age and deprivation quintile for mortality/hospitalization outcomes (p ≤ 0.001). Younger residents (age ≤65 years) of the most versus least deprived neighbourhoods had higher hazards of all-cause death (hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.10-1.29]) and cardiovascular hospitalization (HR 1.29 [95% CI 1.19-1.39]). Older individuals (≥66 years) in the most deprived neighbourhoods had significantly higher hazard of death (HR 1.11 [95% CI 1.08-1.14]) and cardiovascular hospitalization (HR 1.13 [95% CI 1.09-1.18]) compared to the least deprived. The magnitude of the association between deprivation and outcomes was amplified in the younger compared to the older age group. More deprived individuals in both age groups had a lower hazard of cardiology visits and advanced cardiac imaging (all p < 0.001), while the most deprived of younger ages were less likely to undergo implantable cardioverter-defibrillator/cardiac resynchronization therapy-pacemaker implantation (p = 0.023), compared to the least deprived.

CONCLUSION

Patients with newly-diagnosed heart failure residing in the most deprived neighbourhoods had worse outcomes and reduced access to care than those less deprived.

Association of Neighborhood-Level Marginalization With Health Care Use and Clinical Outcomes Following Hospital Discharge in Patients Who Underwent Coronary Catheterization for Acute Myocardial Infarction in a Single-Payer Health Care System

BACKGROUND

Canadian data suggest that patients of lower socioeconomic status with acute myocardial infarction receive less beneficial therapy and have worse clinical outcomes, raising questions regarding care disparities even in universal health care systems. We assessed the contemporary association of marginalization with clinical outcomes and health services use.

METHODS

Using clinical and administrative databases in Ontario, Canada, we conducted a population-based study of patients aged ≥65 years hospitalized for their first acute myocardial infarction between April 1, 2010 and March 1, 2019. Patients receiving cardiac catheterization and surviving 7 days postdischarge were included. Our primary exposure was neighborhood-level marginalization, a multidimensional socioeconomic status metric. Neighborhoods were categorized by quintile from Q1 (least marginalized) to Q5 (most marginalized). Our primary outcome was all-cause mortality. A proportional hazards regression model with a robust variance estimator was used to quantify the association of marginalization with outcomes, adjusting for risk factors, comorbidities, disease severity, and regional cardiologist supply.

RESULTS

Among 53 841 patients (median age, 75 years; 39.1% female) from 20 640 neighborhoods, crude 1- and 3-year mortality rates were 7.7% and 17.2%, respectively. Patients in Q5 had no significant difference in 1-year mortality (hazard ratio [HR], 1.08 [95% CI, 0.95-1.22]), but greater mortality over 3 years (HR, 1.13 [95% CI, 1.03-1.22]) compared with Q1. Over 1 year, we observed differences between Q1 and Q5 in visits to primary care physicians (Q1, 96.7%; Q5, 93.7%) and cardiologists (Q1, 82.6%; Q5, 72.6%), as well as diagnostic testing. There were no differences in secondary prevention medications dispensed or medication adherence at 1 year.

CONCLUSIONS

In older patients with acute myocardial infarction who survived to hospital discharge, those residing in the most marginalized neighborhoods had a greater long-term risk of mortality, less specialist care, and fewer diagnostic tests. Yet, there were no differences across socioeconomic status in prescription medication use and adherence.

Previous Ischemic Stroke Significantly Alters Stroke Risk in Newly Diagnosed Cancer Patients

BACKGROUND

Previous ischemic stroke (IS) is a risk factor for subsequent IS in the general population; it is unclear if this relationship remains true in patients with cancer. Our objective was to examine the association between previous IS and risk for future IS in individuals newly diagnosed with cancer.

METHODS

We conducted a retrospective population-based matched cohort study of newly diagnosed adult cancer patients (excluding nonmelanoma skin cancers and primary central nervous system tumors) in Ontario, Canada from 2010 to 2020; those with prior IS were matched (1:4) by age, sex, year of cancer diagnosis, cancer stage, and cancer site to those without a history of stroke. Cumulative incidence function curves were created to estimate the incidence of IS. Subdistribution adjusted hazard ratios (aHRs) and 95% CIs were calculated, where death was treated as a competing event. Multivariable analysis was adjusted for imbalanced baseline characteristics.

RESULTS

We examined 65 525 individuals with cancer, including 13 070 with a history of IS. The median follow-up duration was 743 days (interquartile range, 177-1729 days). The incidence of IS following cancer diagnosis was 261.3/10 000 person-years in the cohort with prior IS and 75.3/10 000 person-years in those without prior IS. Individuals with prior IS had an increased risk for IS after cancer diagnosis compared with those without a history (aHR, 2.68 [95% CI, 2.41-2.98]); they also had more prevalent cardiovascular risk factors. The highest risk for stroke compared with those without a history of IS was observed in the gynecologic cancer (aHR, 3.84 [95% CI, 2.15-6.85]) and lung cancer (aHR, 3.18 [95% CI, 2.52-4.02]) subgroups. The risk of IS was inversely correlated with lag time of previous stroke; those with IS 1 year before their cancer diagnosis had the highest risk (aHR, 3.68 [95% CI, 3.22-4.22]).

CONCLUSIONS

Among individuals with newly diagnosed cancer, those with IS history were almost 3× more likely to experience a stroke after cancer diagnosis, especially if the prediagnosis stroke occurred within 1 year preceding cancer diagnosis.

Burden of illness associated with Respiratory Syncytial Virus (RSV)-related hospitalizations among adults in Ontario, Canada: A retrospective population-based study

BACKGROUND

Globally, RSV is a common viral pathogen that causes 64 million acute respiratory infections annually. Our objective was to determine the incidence of hospitalization, healthcare resource use and associated costs of adults hospitalized with RSV in Ontario, Canada.

METHODS

To describe the epidemiology of adults hospitalized with RSV, we used a validated algorithm applied to a population-based healthcare utilization administrative dataset in Ontario, Canada. We created a retrospective cohort of incident hospitalized adults with RSV between September 2010 and August 2017 and followed each person for up to two years. To determine the burden of illness associated with hospitalization and post-discharge healthcare encounters each RSV-admitted patient was matched to two unexposed controls based on demographics and risk factors. Patient demographics were described and mean attributable 6-month and 2-year healthcare costs (2019 Canadian dollars) were estimated.

RESULTS

There were 7,091 adults with RSV-associated hospitalizations between 2010 and 2019 with a mean age of 74.6 years; 60.4 % were female. RSV-coded hospitalization rates increased from 1.4 to 14.6 per 100,000 adults between 2010-2011 and 2018-2019. The mean difference in healthcare costs between RSV-admitted patients and matched controls was $28,260 (95 % CI: $27,728 - $28,793) in the first 6 months and $43,721 over 2 years (95 % CI: $40,383 - $47,059) post-hospitalization.

CONCLUSIONS

RSV hospitalizations among adults increased in Ontario between 2010/11 to 2018/19 RSV seasons. RSV hospitalizations in adults were associated with increased attributable short-term and long-term healthcare costs compared to matched controls. Interventions that could prevent RSV in adults may reduce healthcare burden.

Examining antibiotic prescribing and urine culture testing for urinary tract infections (UTIs) in a primary care spinal cord injury (SCI) cohort

STUDY DESIGN

A retrospective cohort study.

OBJECTIVES

To describe antibiotic prescribing and urine culture testing patterns for urinary tract infections (UTIs) in a primary care Spinal Cord Injury (SCI) cohort.

SETTING

A primary care electronic medical records (EMR) database in Ontario.

METHODS

Using linked EMR health administrative databases to identify urine culture and antibiotic prescriptions ordered in primary care for 432 individuals with SCI from January 1, 2013 to December 31, 2015. Descriptive statistics were conducted to describe the SCI cohort, and physicians. Regression analyses were conducted to determine patient and physician factors associated with conducting a urine culture and class of antibiotic prescription.

RESULTS

The average annual number of antibiotic prescriptions for UTI for the SCI cohort during study period was 1.9. Urine cultures were conducted for 58.1% of antibiotic prescriptions. Fluroquinolones and nitrofurantoin were the most frequently prescribed antibiotics. Male physicians and international medical graduates were more likely to prescribe fluroquinolones than nitrofurantoin for UTIs. Early-career physicians were more likely to order a urine culture when prescribing an antibiotic. No patient characteristics were associated with obtaining a urine culture or antibiotic class prescription.

CONCLUSION

Nearly 60% of antibiotic prescriptions for UTIs in the SCI population were associated with a urine culture. Only physician characteristics, not patient characteristics, were associated with whether or not a urine culture was conducted, and the class of antibiotic prescribed. Future research should aim to further understand physician factors with antibiotic prescribing and urine culture testing for UTIs in the SCI population.

Variation and clinical consequences of wait-times for atrial fibrillation ablation: population level study in Ontario, Canada

AIMS

Atrial fibrillation (AF) is the most common cardiac rhythm disorder. Emerging evidence supporting the efficacy of catheter ablation in managing AF has led to increased demand for this therapy, potentially outpacing the capacity to perform this procedure. Mismatch between demand and capacity for AF ablation results in wait-times which have not been comprehensively evaluated at a population level. Additionally, the consequences of such delays in AF ablation, namely the risk of hospitalization or adverse events, have not been studied.

METHODS AND RESULTS

This observational cohort study included adults referred for catheter ablation to treat AF in Ontario, Canada, between 1 April 2016 and 31 March 2020. Wait-time was defined from referral to the earliest of ablation, death, off-list, or the study endpoint of 31 March 2022. The outcomes of interest included a composite of death, hospitalization for AF/heart failure, and emergency department visit for AF/heart failure. Our study cohort included 6253 patients referred for de novo AF ablation. The median wait-time for patients who received and who did not receive ablation was 218 days (IQR: 112-363) and 520 days (IQR: 270-763), respectively. Wait-time increased consistently for patients referred between October 2017 and March 2020. Mortality was rare, but significant morbidity was observed, affecting 19.2% of patients on the waitlist for AF ablation. Paroxysmal AF was associated with a statistically significant greater risk for adverse outcomes on the waitlist (HR 1.51, 95% CI 1.18-1.93).

CONCLUSION

Wait-times for AF ablation are increasing and are associated with significant morbidity.

Data sharing: A Long COVID perspective, challenges, and road map for the future

'Long COVID' is the term used to describe the phenomenon in which patients who have survived a COVID-19 infection continue to experience prolonged SARS-CoV-2 symptoms. Millions of people across the globe are affected by Long COVID. Solving the Long COVID conundrum will require drawing upon the lessons of the COVID-19 pandemic, during which thousands of experts across diverse disciplines such as epidemiology, genomics, medicine, data science, and computer science collaborated, sharing data and pooling resources to attack the problem from multiple angles. Thus far, there has been no global consensus on the definition, diagnosis, and most effective treatment of Long COVID. In this work, we examine the possible applications of data sharing and data science in general with a view to, ultimately, understand Long COVID in greater detail and hasten relief for the millions of people experiencing it. We examine the literature and investigate the current state, challenges, and opportunities of data sharing in Long COVID research.

Twin pregnancy and severe maternal mental illness: a Canadian population-based cohort study

Twin pregnancy is a risk factor for postpartum depression and anxiety. Whether this translates into a higher risk of severe maternal mental illness in the short-term or long-term is unknown. This study was a population-based retrospective cohort study, using linked health administrative databases for the entire province of Ontario, Canada. Included were primiparas aged 15-50 years with a twin vs. singleton hospital livebirth, between January 1, 2003, and March 31, 2019. Propensity-score inverse probability of treatment weights accounted for potential confounding. The primary outcome of severe mental illness comprised a composite of an emergency department visit or hospitalization for mental illness or self-injury, or death by suicide, assessed in the first year after birth, and in long-term follow-up, up to 17 years thereafter. Fifteen thousand twenty-four twin and 796,804 (15,022 weighted) singleton births were included, with a mean (IQR) duration of follow-up of 9 (5-13) years. After weighting, the mean (SD) maternal age was 31.3 (5.5) years. In the first 365 days postpartum, severe mental illness occurred at rates of 10.5 and 8.7 per 1000 person-years in twin and singleton mothers, respectively, corresponding to a hazard ratio (HR) of 1.21 (95% CI 1.07-1.47). From 366 days onward, the corresponding figures were 5.9 and 6.1 per 1000 person-years (HR 0.96, 95% CI 0.89-1.04). Individuals with a twin birth appear to experience an increased risk for severe mental illness in the first year postpartum, but not thereafter. This suggests a potential need for targeted counselling and mental health services for mothers within the first year after birth.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

INTERPRETATION

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.

The price of neonatal intensive care outcomes - in-hospital costs of morbidities related to preterm birth

BACKGROUND

Neonatal care for preterm babies is prolonged and expensive. Our aim was to analyze and report costs associated with common preterm diagnoses during NICU stay.

METHODS

We analyzed data from the Ontario healthcare data service. Diagnoses were collated by discharge ICD codes, and categorized by gestational age. We calculated typical non parametric statistics, and for each diagnosis we calculated median shifts and generalized linear mode.

RESULTS

We included data on 12,660 infants between 23 and 30 weeks gestation in 2005-2017. Calculated cost increment with diagnosis were: Intestinal obstruction: $94,738.08 (95%CI: $70,093.3, $117,294.2), Ventriculoperitoneal shunt: $86,456.60 (95%CI: $60,773.7, $111,552.2), Chronic Lung Disease $77,497.70 (95%CI: $74,937.2, $80,012.8), Intestinal perforation $57,997.15 (95%CI:$45,324.7, $70,652.6), Retinopathy of Prematurity: $55,761.80 (95%CI: $53,916.2, $57,620.1), Patent Ductus Arteriosus $53,453.70 (95%CI: $51,206.9, $55692.7, Post-haemorrhagic ventriculomegaly $41,822.50 (95%CI: $34,590.4, $48,872.4), Necrotizing Enterocolitis $39,785 (95%CI: $35,728.9, $43,879), Meningitis $38,871.85 (95%CI: $25,272.7, $52,224.4), Late onset sepsis $32,954.20 (95%CI: $30,403.7, 35.515), Feeding difficulties $24,820.90 (95%CI: $22,553.3, $27,064.7), Pneumonia $23,781.70 (95%CI: $18,623.8, $28,881.6), Grade >2 Intraventricular Haemorrhage $14,777.38 (95%CI: $9,821.7, $20,085.2). Adjusted generalized linear model of diagnoses as coefficients for cost confirmed significance and robustness of the model.

CONCLUSION

Cost of care for preterm infant is expensive, and significantly increases with prematurity complication. Interventions to reduce those complications may enable resource allocation and better understanding of the needs of the neonatal health services.

Navigator programme for hospitalised adults experiencing homelessness: protocol for a pragmatic randomised controlled trial

INTRODUCTION

People experiencing homelessness suffer from poor outcomes after hospitalisation due to systemic barriers to care, suboptimal transitions of care, and intersecting health and social burdens. Case management programmes have been shown to improve housing stability, but their effects on broad posthospital outcomes in this population have not been rigorously evaluated. The Navigator Programme is a Critical Time Intervention case management programme that was developed to help homeless patients with their postdischarge needs and to link them with community-based health and social services. This randomised controlled trial examines the impact of the Navigator Programme on posthospital outcomes among adults experiencing homelessness.

METHODS AND ANALYSIS

This is a pragmatic randomised controlled trial testing the effectiveness of the Navigator Programme at an urban academic teaching hospital and an urban community teaching hospital in Toronto, Canada. Six hundred and forty adults experiencing homelessness who are admitted to the hospital will be randomised to receive support from a Homeless Outreach Counsellor for 90 days after hospital discharge or to usual care. The primary outcome is follow-up with a primary care provider (physician or nurse practitioner) within 14 days of hospital discharge. Secondary outcomes include postdischarge mortality or readmission, number of days in hospital, number of emergency department visits, self-reported care transition quality, and difficulties meeting subsistence needs. Quantitative outcomes are being collected over a 180-day period through linked patient-reported and administrative health data. A parallel mixed-methods process evaluation will be conducted to explore intervention context, implementation and mechanisms of impact.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Unity Health Toronto Research Ethics Board. Participants will be required to provide written informed consent. Results of the main trial and process evaluation will be reported in peer-reviewed journals and shared with hospital leadership, community partners and policy makers.

TRIAL REGISTRATION NUMBER

NCT04961762.

Post-acute health care burden after SARS-CoV-2 infection: a retrospective cohort study

BACKGROUND

The post-acute burden of health care use after SARS-CoV-2 infection is unknown. We sought to quantify the post-acute burden of health care use after SARS-CoV-2 infection among community-dwelling adults in Ontario by comparing those with positive and negative polymerase chain reaction (PCR) test results for SARS-CoV-2 infection.

METHODS

We conducted a retrospective cohort study involving community-dwelling adults in Ontario who had a PCR test between Jan. 1, 2020, and Mar. 31, 2021. Follow-up began 56 days after PCR testing. We matched people 1:1 on a comprehensive propensity score. We compared per-person-year rates for health care encounters at the mean and 99th percentiles, and compared counts using negative binomial models, stratified by sex.

RESULTS

Among 531 702 matched people, mean age was 44 (standard deviation [SD] 17) years and 51% were female. Females who tested positive for SARS-CoV-2 had a mean of 1.98 (95% CI 1.63 to 2.29) more health care encounters overall per-person-year than those who had a negative test result, with 0.31 (95% CI 0.05 to 0.56) more home care encounters to 0.81 (95% CI 0.69 to 0.93) more long-term care days. At the 99th percentile per-person-year, females who tested positive had 6.48 more days of hospital admission and 28.37 more home care encounters. Males who tested positive for SARS-CoV-2 had 0.66 (95% CI 0.34 to 0.99) more overall health care encounters per-person-year than those who tested negative, with 0.14 (95% CI 0.06 to 0.21) more outpatient encounters and 0.48 (95% CI 0.36 to 0.60) long-term care days, and 0.43 (95% CI -0.67 to -0.21) fewer home care encounters. At the 99th percentile, they had 8.69 more days in hospital per-person-year, with fewer home care (-27.31) and outpatient (-0.87) encounters.

INTERPRETATION

We found significantly higher rates of health care use after a positive SARS-CoV-2 PCR test in an analysis that matched test-positive with test-negative people. Stakeholders can use these findings to prepare for health care demand associated with post-COVID-19 condition (long COVID).

Fracture definitions in observational osteoporosis drug effects studies that leverage healthcare administrative (claims) data: a scoping review

Healthcare administrative (claims) data are commonly utilized to estimate drug effects. We identified considerable heterogeneity in fracture outcome definitions in a scoping review of 57 studies that estimated osteoporosis drug effects on fracture risk. Better understanding of the impact of different fracture definitions on study results is needed.

PURPOSE

Healthcare administrative (claims) data are frequently used to estimate the real-world effects of drugs. Fracture incidence is a common outcome of osteoporosis drug studies. We aimed to describe how fractures are defined in studies that use claims data.

METHODS

We searched MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCO), and gray literature for studies published in English between 2000 and 2020 that estimated fracture effectiveness (hip, humerus, radius/ulna, vertebra) or safety (atypical fracture of the femur, AFF) of osteoporosis drugs using claims data in Canada and the USA. Literature searches, screening and data abstraction were completed independently by two reviewers.

RESULTS

We identified 57 eligible studies (52 effectiveness, 3 safety, 2 both). Hip fracture was the most common fracture site studied (93%), followed by humerus (66%), radius/ulna (59%), vertebra (61%), and AFF (9%). Half (n = 29) of the studies did not indicate specific data sources, codes, or cite a validation paper. Of the papers with sufficient detail, heterogeneity in fracture definitions was common. The most common definition within each fracture site was used by less than half of the studies that examined effectiveness (12 definitions in 29 hip fracture papers, 8 definitions in 17 humerus papers, 8 definitions in 13 radius/ulna papers, 9 definitions in 15 vertebra papers), and 3 definitions among 4 AFF papers.

CONCLUSION

There is ambiguity and heterogeneity in fracture outcome definitions in studies that leverage claims data. Better transparency in outcome reporting is needed. Future exploration of how fracture definitions impact study results is warranted.

The Association Between Telemedicine Use and Changes in Health Care Usage and Outcomes in Patients With Congestive Heart Failure: Retrospective Cohort Study

Background

Telemedicine use has become widespread owing to the COVID-19 pandemic, but its impact on patient outcomes remains unclear.

Objective

We sought to investigate the effect of telemedicine use on changes in health care usage and clinical outcomes in patients diagnosed with congestive heart failure (CHF).

Methods

We conducted a population-based retrospective cohort study using administrative data in Ontario, Canada. Patients were included if they had at least one ambulatory visit between March 14 and September 30, 2020, and a heart failure diagnosis any time prior to March 14, 2020. Telemedicine users were propensity score–matched with unexposed users based on several baseline characteristics. Monthly use of various health care services was compared between the 2 groups during 12 months before to 3 months after their index in-person or telemedicine ambulatory visit after March 14, 2020, using generalized estimating equations.

Results

A total of 11,131 pairs of telemedicine and unexposed patients were identified after matching (49% male; mean age 78.9, SD 12.0 years). All patients showed significant reductions in health service usage from pre- to postindex visit. There was a greater decline across time in the unexposed group than in the telemedicine group for CHF admissions (ratio of slopes for high- vs low-frequency users 1.02, 95% CI 1.02-1.03), cardiovascular admissions (1.03, 95% CI 1.02-1.04), any-cause admissions (1.03, 95% CI 1.02-1.04), any-cause ED visits (1.03, 95% CI 1.03-1.04), visits with any cardiologist (1.01, 95% CI 1.01-1.02), laboratory tests (1.02, 95% CI 1.02-1.03), diagnostic tests (1.04, 95% CI 1.03-1.05), and new prescriptions (1.02, 95% CI 1.01-1.03). However, the decline in primary care visit rates was steeper among telemedicine patients than among unexposed patients (ratio of slopes 0.99, 95% CI 0.99-1.00).

Conclusions

Overall health care usage over time appeared higher among telemedicine users than among low-frequency users or nonusers, suggesting that telemedicine was used by patients with the greatest need or that it allowed patients to have better access or continuity of care among those who received it.

Ku-gaa-gii pimitizi-win, the COVID-19 cohort study of people experiencing homelessness in Toronto, Canada: a study protocol

Introduction

Initial reports suggest people experiencing homelessness (PEH) are at high risk for SARS-CoV-2 infection and associated morbidity and mortality. However, there have been few longitudinal evaluations of the spread and impact of COVID-19 among PEH. This study will estimate the prevalence and incidence of COVID-19 infections in a cohort of PEH followed prospectively in Toronto, Canada. It will also examine associations between individual-level and shelter-level characteristics with COVID-19 infection, adverse health outcomes related to infection and vaccination. Finally, the data will be used to develop and parameterise a mathematical model to characterise SARS-CoV-2 transmission dynamics, and the transmission impact of interventions serving PEH.

Design, methods and analysis

Ku-gaa-gii pimitizi-win will follow a random sample of PEH from across Toronto (Canada) for 12 months. 736 participants were enrolled between June and September 2021, and will be followed up at 3-month intervals. At each interval, specimens (saliva, capillary blood) will be collected to determine active SARS-CoV-2 infection and serologic evidence of past infection and/or vaccination, and a detailed survey will gather self-reported information, including a detailed housing history. To examine the association between individual-level and shelter-level characteristics on COVID-19-related infection, adverse outcomes, and vaccination, shelter and healthcare administrative data will be linked to participant study data. Healthcare administrative data will also be used to examine long-term (up to 5 years) COVID-19-related outcomes among participants.

Ethics and dissemination

Ethical approval was obtained from the Unity Health Toronto and University of Toronto Health Sciences Research Ethics Boards (# 20-272). Ku-gaa-gii pimitizi-win was designed in collaboration with community and service provider partners and people having lived experience of homelessness. Findings will be reported to groups supporting Ku-gaa-gii pimitizi-win, Indigenous and other community partners and service providers, funding bodies, public health agencies and all levels of government to inform policy and public health programs.

The burden of cancer among people living with HIV in Ontario, Canada, 1997-2020: a retrospective population-based cohort study using administrative health data

BACKGROUND

With combination antiretroviral therapy (ART) and increased longevity, cancer is a leading cause of morbidity among people with HIV. We characterized trends in cancer burden among people with HIV in Ontario, Canada, between 1997 and 2020.

METHODS

We conducted a population-based, retrospective cohort study of adults with HIV using linked administrative health databases from Jan. 1, 1997, to Nov. 1, 2020. We grouped cancers as infection-related AIDS-defining cancers (ADCs), infection-related non-ADCs (NADCs) and infection-unrelated cancers. We calculated age-standardized incidence rates per 100 000 person-years with 95% confidence intervals (CIs) using direct standardization, stratified by calendar period and sex. We also calculated limited-duration prevalence.

RESULTS

Among 19 403 adults living with HIV (79% males), 1275 incident cancers were diagnosed. From 1997-2000 to 2016- 2020, we saw a decrease in the incidence of all cancers (1113.9 [95% CI 657.7-1765.6] to 683.5 [95% CI 613.4-759.4] per 100 000 person-years), ADCs (403.1 [95% CI 194.2-739.0] to 103.8 [95% CI 79.2-133.6] per 100 000 person-years) and infection-related NADCs (196.6 [95% CI 37.9-591.9] to 121.9 [95% CI 94.3-154.9] per 100 000 person-years). The incidence of infection-unrelated cancers was stable at 451.0 per 100 000 person-years (95% CI 410.3-494.7). The incidence of cancer among females increased over time but was similar to that of males in 2016-2020.

INTERPRETATION

Over a 24-year period, the incidence of cancer decreased overall, largely driven by a considerable decrease in the incidence of ADC, whereas the incidence of infection-unrelated cancer remained unchanged and contributed to the greatest burden of cancer. These findings could reflect combination ART-mediated changes in infectious comorbidity and increased life expectancy; targeted cancer screening and prevention strategies are needed.

Hospitalizations During the COVID-19 Pandemic Among Recently Homeless Individuals: a Retrospective Population-Based Matched Cohort Study

BACKGROUND

Hospitalizations fell precipitously among the general population during the COVID-19 pandemic. It remains unclear whether individuals experiencing homelessness experienced similar reductions.

OBJECTIVE

To examine how overall and cause-specific hospitalizations changed among individuals with a recent history of homelessness (IRHH) and their housed counterparts during the first wave of the COVID-19 pandemic, using corresponding weeks in 2019 as a historical control.

DESIGN

Population-based cohort study conducted in Ontario, Canada, between September 30, 2018, and September 26, 2020.

PARTICIPANTS

In total, 38,617 IRHH, 15,022,368 housed individuals, and 186,858 low-income housed individuals matched on age, sex, rurality, and comorbidity burden.

MAIN MEASURES

Primary outcomes included medical-surgical, non-elective (overall and cause-specific), elective surgical, and psychiatric hospital admissions.

KEY RESULTS

Average rates of medical-surgical (rate ratio: 3.8, 95% CI: 3.7-3.8), non-elective (10.3, 95% CI: 10.1-10.4), and psychiatric admissions (128.1, 95% CI: 126.1-130.1) between January and September 2020 were substantially higher among IRHH compared to housed individuals. During the peak period (March 17 to June 16, 2020), rates of medical-surgical (0.47, 95% CI: 0.47-0.47), non-elective (0.80, 95% CI: 0.79-0.80), and psychiatric admissions (0.86, 95% CI: 0.84-0.88) were significantly lower among housed individuals relative to equivalent weeks in 2019. No significant changes were observed among IRHH. During the re-opening period (June 17-September 26, 2020), rates of non-elective hospitalizations for liver disease (1.41, 95% CI: 1.23-1.69), kidney disease (1.29, 95% CI: 1.14-1.47), and trauma (1.19, 95% CI: 1.07-1.32) increased substantially among IRHH but not housed individuals. Distinct hospitalization patterns were observed among IRHH even in comparison with more medically and socially vulnerable matched housed individuals.

CONCLUSIONS

Persistence in overall hospital admissions and increases in non-elective hospitalizations for liver disease, kidney disease, and trauma indicate that the COVID-19 pandemic presented unique challenges for recently homeless individuals. Health systems must better address the needs of this population during public health crises.

What makes administrative data "research-ready"? A systematic review and thematic analysis of published literature

Introduction

Administrative data are a valuable research resource, but are under-utilised in the UK due to governance, technical and other barriers (e.g., the time and effort taken to gain secure data access). In recent years, there has been considerable government investment in making administrative data "research-ready", but there is no definition of what this term means. A common understanding of what constitutes research-ready administrative data is needed to establish clear principles and frameworks for their development and the realisation of their full research potential.

Objective

To define the characteristics of research-ready administrative data based on a systematic review and synthesis of existing literature.

Methods

On 29th June 2021, we systematically searched seven electronic databases for (1) peer-reviewed literature (2) related to research-ready administrative data (3) written in the English language. Following supplementary searches and snowball screening, we conducted a thematic analysis of the identified relevant literature.

Results

Overall, we screened 2,375 records and identified 38 relevant studies published between 2012 and 2021. Most related to administrative data from the UK and US and particularly to health data. The term research-ready was used inconsistently in the literature and there was some conflation with the concept of data being ready for statistical analysis. From the thematic analysis, we identified five defining characteristics of research-ready administrative data: (a) accessible, (b) broad, (c) curated, (d) documented and (e) enhanced for research purposes.

Conclusions

Our proposed characteristics of research-ready administrative data could act as a starting point to help data owners and researchers develop common principles and standards. In the more immediate term, the proposed characteristics are a useful framework for cataloguing existing research-ready administrative databases and relevant resources that can support their development.

Virtual care use during the COVID-19 pandemic and its impact on healthcare utilization in patients with chronic disease: A population-based repeated cross-sectional study

Purpose

It is currently unclear how the shift towards virtual care during the 2019 novel coronavirus (COVID-19) pandemic may have impacted chronic disease management at a population level. The goals of our study were to provide a description of the levels of use of virtual care services relative to in-person care in patients with chronic disease across Ontario, Canada and to describe levels of healthcare utilization in low versus high virtual care users.

Methods

We used linked health administrative data to conduct a population-based, repeated cross-sectional study of all ambulatory patient visits in Ontario, Canada (January 1, 2018 to January 16, 2021). Further stratifications were also completed to examine patients with COPD, heart failure, asthma, hypertension, diabetes, mental illness, and angina. Patients were classified as low (max 1 virtual care visit) vs. high virtual care users. A time-series analysis was done using interventional autoregressive integrated moving average (ARIMA) modelling on weekly hospitalizations, outpatient visits, and diagnostic tests.

Results

The use of virtual care increased across all chronic disease patient populations. Virtual care constituted at least half of the total care in all conditions. Both low and high virtual care user groups experienced a statistically significant reduction in hospitalizations and laboratory testing at the start of the pandemic. Hospitalization volumes increased again only among the high users, while testing increased in both groups. Outpatient visits among high users remained unaffected by the pandemic but dropped in low users.

Conclusion

The decrease of in-person care during the pandemic was accompanied by an increase in virtual care, which ultimately allowed patients with chronic disease to return to the same visit rate as they had before the onset of the pandemic. Virtual care was adopted across various chronic conditions, but the relative adoption of virtual care varied by condition with highest rates seen in mental health.

Developing a random forest algorithm to identify patent foramen ovale and atrial septal defects in Ontario administrative databases

Purpose

Routinely collected administrative data is widely used for population-based research. However, although clinically very different, atrial septal defects (ASD) and patent foramen ovale (PFO) share a single diagnostic code (ICD-9: 745.5, ICD-10: Q21.1). Using machine-learning based approaches, we developed and validated an algorithm to differentiate between PFO and ASD patient populations within healthcare administrative data.

Methods

Using data housed at ICES, we identified patients who underwent transcatheter closure in Ontario between October 2002 and December 2017 using a Canadian Classification of Interventions code (1HN80GPFL, N = 4680). A novel random forest model was developed using demographic and clinical information to differentiate those who underwent transcatheter closure for PFO or ASD. Those patients who had undergone transcatheter closure and had records in the CorHealth Ontario cardiac procedure registry (N = 1482) were used as the reference standard. Several algorithms were tested and evaluated for accuracy, sensitivity, and specificity. Variable importance was examined via mean decrease in Gini index.

Results

We tested 7 models in total. The final model included 24 variables, including demographic, comorbidity, and procedural information. After hyperparameter tuning, the final model achieved 0.76 accuracy, 0.76 sensitivity, and 0.75 specificity. Patient age group had the greatest influence on node impurity, and thus ranked highest in variable importance.

Conclusions

Our random forest classification method achieved reasonable accuracy in identifying PFO and ASD closure in administrative data. The algorithm can now be applied to evaluate long term PFO and ASD closure outcomes in Ontario, pending future external validation studies to further test the algorithm.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-022-01837-2.

Describing the linkage between administrative social assistance and health care databases in Ontario, Canada

Background

The linkage of records across administrative databases has become a powerful tool to increase information available to undertake research and analytics in a privacy protective manner.

Objective

The objective of this paper was to describe the data integration strategy used to link the Ontario Ministry of Children, Community and Social Services (MCCSS)-Social Assistance (SA) database with administrative health care data.

Methods

Deterministic and probabilistic linkage methods were used to link the MCCSS-SA database (2003-2016) to the Registered Persons Database, a population registry containing data on all individuals issued a health card number in Ontario, Canada. Linkage rates were estimated, and the degree of record linkage and representativeness of the dataset were evaluated by comparing socio-demographic characteristics of linked and unlinked records.

Results

There were a total of 2,736,353 unique member IDs in the MCCSS-SA database from the 1^st January 2003 to 31^st December 2016; 331,238 (12.1%) were unlinked (linkage rate = 87.9%). Despite 16 passes, most record linkages were obtained after 2 deterministic (76.2%) and 14 probabilistic passes (11.7%). Linked and unlinked samples were similar for most socio-demographic characteristics (i.e., sex, age, rural dwelling), except migrant status (non-migrant versus migrant) (standardized difference of 0.52). Linked and unlinked records were also different for SA program-specific characteristics, such as social assistance program, Ontario Works and Ontario Disability Support Program (standardized difference of 0.20 for each), data entry system, Service Delivery Model Technology only and both Service Delivery Model Technology and Social Assistance Management System (standardized difference of 0.53 and 0.52, respectively), and months on social assistance (standardized difference of 0.43).

Conclusions

Additional techniques to account for sub-optimal linkage rates may be required to address potential biases resulting from this data linkage. Nonetheless, the linkage between administrative social assistance and health care data will provide important findings on the social determinants of health.

Pivoting data and analytic capacity to support Ontario's COVID-19 response

Introduction

Health care systems have faced unprecedented challenges due to the COVID-19 pandemic. Access to timely population-based data has been vital to informing public health policy and practice.

Methods

We describe how ICES, an independent not-for-profit research and analytic institute in Ontario, Canada, pivoted existing research infrastructure and engaged health system stakeholders to provide near real-time population-based data and analytics to support Ontario's COVID-19 pandemic response.

Results

Since April 2020, ICES provided the Ontario COVID-19 Provincial Command Table and public health partners with regular and ad hoc reports on SARS-CoV-2 testing and COVID-19 vaccine coverage. These reports: 1) helped identify congregate care/shared living settings that needed testing and prevention efforts early in the pandemic; 2) provided early indications of inequities in testing and infection in marginalized neighbourhoods, including areas with higher proportions of immigrants and visible minorities; 3) identified areas with high test positivity, which helped Public Health Units target and evaluate prevention efforts; and 4) contributed to altering the province's COVID-19 vaccine roll-out strategy to target high-risk neighbourhoods and helping Public Health Units and community organizations plan local vaccination programs. In addition, ICES is a key component of the Ontario Health Data Platform, which provides scientists with data access to conduct COVID-19 research and analyses.

Discussion and Conclusion

ICES was well-positioned to provide rapid analyses for decision-makers to respond to the evolving public health emergency, and continues to contribute to Ontario's pandemic response by providing timely, relevant reports to health system stakeholders and facilitating data access for externally-funded COVID-19 research.

Changes in mammography screening in Ontario and Alberta following national guideline dissemination: an interrupted time series analysis

Background: In November 2011, the Canadian Task Force on Preventive Health Care released guidelines for screening women at average breast cancer risk. Weak recommendations (framed using GRADE methodology) were made for screening women aged 50 to 74 years every two to three years, and for not screening women aged 40 to 49 years. Methods: We conducted an interrupted time series analysis using administrative data to examine bilateral mammography use before and after a national guideline dissemination strategy targeting primary care physicians. Women aged 40 to 74 years living in Ontario or Alberta from 30 th November 2008 to 30 th November 2014 were included. Strata included age, region of residence, neighbourhood income quintile, immigration status, and education level. Results: In both provinces, mammography use rates were lower in the post-intervention period (527 vs. 556 and 428 vs. 465/1000 participant-months - the monthly screening rate/1000 - in Ontario and Alberta, respectively). In Ontario, mammography trends decreased following guideline release to align with recommendations for women aged 40 to 74 (decrease of 2.21/1000 women, SE 0.26/1000, p<0.0001). In Alberta, mammography trends decreased for women aged 40 to 49 years (3/1000 women, SE 0.32, p<0.001) and 50 to 69 (2.9/1000 women, SE 0.79, p<0.001), but did not change for women aged 70 to 74 (0.7/1000 women, SE 1.23, p=0.553). In both provinces, trends in mammography use rates were sustained for up to three years after guideline release. Conclusions: The guideline dissemination strategy appeared to increase uptake of guideline-concordant screening practice in women aged 40 to 49 years in Ontario and Alberta and for women aged 50 to 74 years in Ontario. Further work is required to understand these findings and whether shared decision making about mammography between women and providers increased among women considering mammography.

Changes in mammography screening in Ontario and Alberta following national guideline dissemination: an interrupted time series analysis

Background: In November 2011, the Canadian Task Force on Preventive Health Care released guidelines for screening women at average breast cancer risk. Weak recommendations (framed using GRADE methodology) were made for screening women aged 50 to 74 years every two to three years, and for not screening women aged 40 to 49 years. Methods: We conducted an interrupted time series analysis using administrative data to examine bilateral mammography use before and after a release of a national breast screening guideline. Women aged 40 to 74 years living in Ontario or Alberta from 30th November 2008 to 30th November 2014 were included. Strata included age, region of residence, neighbourhood income quintile, immigration status, and education level. Results: In both provinces, mammography use rates were lower in the post-intervention period (527 vs. 556 and 428 vs. 465/1000 women in Ontario and Alberta, respectively). In Ontario, mammography trends decreased following guideline release to align with recommendations for women aged 40 to 74 (decrease of 2.21/1000 women, SE 0.26/1000, p<0.0001). In Alberta, mammography trends decreased for women aged 40 to 49 years (3/1000 women, SE 0.32, p<0.001) and 50 to 69 (2.9/1000 women, SE 0.79, p<0.001), but did not change for women aged 70 to 74 (0.7/1000 women, SE 1.23, p=0.553). In both provinces, trends in mammography use rates were sustained for up to three years after guideline release. Conclusions: We observed a decrease in screening for women aged 40-49. Additional research to explore whether shared decision making was used to optimize guideline-concordant screening for women aged 50-74 is needed.

Rural Telemedicine Use Before and During the COVID-19 Pandemic: Repeated Cross-sectional Study

Background

The COVID-19 pandemic has led to a notable increase in telemedicine adoption. However, the impact of the pandemic on telemedicine use at a population level in rural and remote settings remains unclear.

Objective

This study aimed to evaluate changes in the rate of telemedicine use among rural populations and identify patient characteristics associated with telemedicine use prior to and during the pandemic.

Methods

We conducted a repeated cross-sectional study on all monthly and quarterly rural telemedicine visits from January 2012 to June 2020, using administrative data from Ontario, Canada. We compared the changes in telemedicine use among residents of rural and urban regions of Ontario prior to and during the pandemic.

Results

Before the pandemic, telemedicine use was steadily low in 2012-2019 for both rural and urban populations but slightly higher overall for rural patients (11 visits per 1000 patients vs 7 visits per 1000 patients in December 2019, P<.001). The rate of telemedicine visits among rural patients significantly increased to 147 visits per 1000 patients in June 2020. A similar but steeper increase (P=.15) was observed among urban patients (220 visits per 1000 urban patients). Telemedicine use increased across all age groups, with the highest rates reported among older adults aged ≥65 years (77 visits per 100 patients in 2020). The proportions of patients with at least 1 telemedicine visit were similar across the adult age groups (n=82,246/290,401, 28.3% for patients aged 18-49 years, n=79,339/290,401, 27.3% for patients aged 50-64 years, and n=80,833/290,401, 27.8% for patients aged 65-79 years), but lower among younger patients <18 years (n=23,699/290,401, 8.2%) and older patients ≥80 years (n=24,284/290,401, 8.4%) in 2020 (P<.001). There were more female users than male users of telemedicine (n=158,643/290,401, 54.6% vs n=131,758/290,401, 45.4%, respectively, in 2020; P<.001). There was a significantly higher proportion of telemedicine users residing in relatively less rural than in more rural regions (n=261,814/290,401, 90.2% vs n=28,587/290,401, 9.8%, respectively, in 2020; P<.001).

Conclusions

Telemedicine adoption increased in rural and remote areas during the COVID-19 pandemic, but its use increased in urban and less rural populations. Future studies should investigate the potential barriers to telemedicine use among rural patients and the impact of rural telemedicine on patient health care utilization and outcomes.

Public engagement can change your research, but how can it change your research institution? ICES case study

This article explores the approach that ICES (formerly the Institute for Clinical Evaluative Sciences) uses to encourage public engagement at both the research study and corporate level. ICES is an independent not-for-profit research institute in the province of Ontario, Canada. This article was co-written by ICES' public engagement team and four members of the ICES Public Advisory Council (PAC). As part of the process of writing this article PAC members provided their reflections on why they got involved, what worked well and the limitations and challenges of ICES' approach. ICES described the development of its public engagement strategy to inform how the institution would capture and incorporate the values of Ontarians in ICES activities and research. ICES provided details on two key elements of its strategy: the formation of a PAC to advise its leadership, and the creation of resources and supports to encourage researchers to incorporate public engagement in their projects. PAC members and ICES provided perspectives on what impact they perceive as a result of the public engagement strategy. PAC members expressed that ICES has demonstrated listening to and using their input, but it is too early to evaluate if their feedback has changed the way ICES conducts its work. ICES discussed the challenges and successes in building and implementing the public engagement strategy, including recruiting a diverse council, aligning with public priorities and creating a culture of engagement. As a result of public input, ICES has restructured the way the institution explains its privacy and cybersecurity approach to build trust and confidence. ICES has also seen an increase in researchers using public engagement resources, and early data suggests that in 2019 about 20% of scientists included some form of public engagement in their projects. ICES' journey to public engagement resulted in important changes to processes and activities at the institution, but there is much more that needs to be done. PAC members advocate that public members should be engaged in health data research and hope that public input will be a core element in health data research in the future. ICES will continue its efforts to address public priorities and will seek to further evaluate the impact of public engagement across the organisation.

Determining the Cancer Diagnostic Interval Using Administrative Health Care Data in a Breast Cancer Cohort

PURPOSE

Population-based administrative health care data could be a valuable resource with which to study the cancer diagnostic interval. The objective of the current study was to determine the first encounter in the diagnostic interval and compute that interval in a cohort of patients with breast cancer using an empirical approach.

METHODS

This is a retrospective cohort study of patients with breast cancer diagnosed in Ontario, Canada, between 2007 and 2015. We used cancer registry, physician claims, hospital discharge, and emergency department visit data to identify and categorize cancer-related encounters that were more common in the three months before diagnosis. We used statistical control charts to define lookback periods for each encounter category. We identified the earliest cancer-related encounter that marked the start of the diagnostic interval. The end of the interval was the cancer diagnosis date.

RESULTS

The final cohort included 69,717 patients with breast cancer. We identified an initial encounter in 97.8% of patients. Median diagnostic interval was 36 days (interquartile range [IQR], 19 to 71 days). Median interval decreased with increasing stage at diagnosis and varied across initial encounter categories, from 9 days (IQR, 1 to 35 days) for encounters with other cancer as the diagnosis to 231 days (IQR 77 to 311 days) for encounters with cyst aspiration or drainage as the procedure.

CONCLUSION

Diagnostic interval research can inform early detection guidelines and assess the success of diagnostic assessment programs. Use of administrative data for this purpose is a powerful tool for improving diagnostic processes at the population level.