Variations and inequities in access to cardiac diagnostic services in Ontario Canada

OBJECTIVES

Echocardiography is an essential diagnostic modality known to have wide regional utilization variations. This study's objectives were to quantify regional variations and to examine the extent to which they are explained by differences in population age, sex, cardiac disease prevalence (CDP), and social determinants of health (SDH) risk.

METHODS

This is an observational study of all echocardiography exams performed in Ontario in 2019/20 (n = 695,622). We measured regional variations in echocardiography crude rates and progressively standardized rates for population age, sex, CDP, and SDH risk.

RESULTS

After controlling for differences in population age, sex, and CDP, Ontario's highest rate regions had echocardiography rates 57% higher than its lowest rate regions. Forty eight percent of total variation was not explained by differences in age, sex, and CDP. CDP increased with SDH risk. Access to most cardiac diagnostics was negatively correlated with SDH risk, while cardiac catheterization rates were positively correlated with SDH risk.

CONCLUSION

Variations analysis that adjusts for age and sex only without including clinical measures of need are likely to overestimate the unwarranted portion of total variation. Substantial variations persisted despite a mandatory provider accreditation policy aimed at curtailing them. The associations between variations and SDH risks imply a need to redress access and outcome inequities.

A Retrospective Cohort Analysis of Mental Health-Related Emergency Department Visits Among Veterans and Non-Veterans Residing in Ontario, Canada: Une analyse de cohorte rétrospective des visites au service d'urgence liées à la santé mentale parmi les vétérans et non-vétérans résidant en Ontario, Canada

OBJECTIVES

Emergency departments (EDs) are a vital part of healthcare systems, at times acting as a gateway to community-based mental health (MH) services. This may be particularly true for veterans of the Royal Canadian Mounted Police who were released prior to 2013 and the Canadian Armed Forces, as these individuals transition from federal to provincial healthcare coverage on release and may use EDs because of delays in obtaining a primary care provider. We aimed to estimate the hazard ratio (HR) of MH-related ED visits between veterans and non-veterans residing in Ontario, Canada: (1) overall; and by (2) sex; and (3) length of service.

METHODS

This retrospective cohort study used administrative healthcare data from 18,837 veterans and 75,348 age-, sex-, geography-, and income-matched non-veterans residing in Ontario, Canada between April 1, 2002, and March 31, 2020. Anderson-Gill regression models were used to estimate the HR of recurrent MH-related ED visits during the period of follow-up. Sex and length of service were used as stratification variables in the models.

RESULTS

Veterans had a higher adjusted HR (aHR) of MH-related ED visits than non-veterans (aHR, 1.97, 95% CI, 1.70 to 2.29). A stronger effect was observed among females (aHR, 3.29; 95% CI, 1.96 to 5.53) than males (aHR, 1.78; 95% CI, 1.57 to 2.01). Veterans who served for 5-9 years had a higher rate of use than non-veterans (aHR, 3.76; 95% CI, 2.34 to 6.02) while veterans who served for 30+ years had a lower rate compared to non-veterans (aHR, 0.60; 95% CI, 0.42 à 0.84).

CONCLUSIONS

Rates of MH-related ED visits are higher among veterans overall compared to members of the Ontario general population, but usage is influenced by sex and length of service. These findings indicate that certain subpopulations of veterans, including females and those with fewer years of service, may have greater acute mental healthcare needs and/or reduced access to primary mental healthcare.

The seroprevalence and risk factors for exposure to Neospora caninum and Neospora hughesi in Ontario broodmares

The seroprevalence and risk factors for exposure to Neospora caninum and Neospora hughesi in broodmares in Ontario were investigated. Sixty of the 219 (27.4%) study broodmares were seropositive for N. caninum and 65/219 (29.7%) for N. hughesi with cut-offs of ≥1:40 and ≥1:160, respectively. Thirty-one of 63 participating farms (49.2%) had at least 1 broodmare seropositive for N. caninum. Thirty-three of the 63 (52.4%) participating farms had at least 1 broodmare positive for N. hughesi. Risk factors for N. caninum included presence of farm dogs (OR = 6.70; 95% CI = 2.14-20.97; p = 0.001), and high stocking density (OR = 2.83; 95% CI = 1.27-6.30; p = 0.011). Presence of livestock, excluding cattle, was associated with reduced risk of exposure (OR = 0.17; 95% CI = 0.06-0.53; p = 0.002). The only risk factor for exposure to N. hughesi was feeding hay on the ground in the paddock (OR = 4.31; 95% CI = 1.65-11.22; p = 0.003). This study demonstrated widespread exposure to Neospora spp. in broodmares in Ontario.

Nivolumab in Squamous Cell Carcinomas of the Head and Neck (SCCHN): A Real-world Outcome Study in Ontario, Canada

The CheckMate-141 trial led to the approval of nivolumab in platinum-resistant metastatic/advanced squamous cell carcinomas of the head and neck (SCCHN). We evaluated the outcomes of SCCHN patients in Ontario, Canada, treated with nivolumab through retrospective review of the provincial treatment registry. Kaplan-Meier method was used to estimate overall survival (OS) and Cox regression to evaluate the prognostic effect of selected factors. Nivolumab was used as second-line therapy after disease relapse for curative-intent platinum chemotherapy (PC) (indication 1-I1), as second-line therapy post-PC in noncurative intent (indication 2-I2), and as first-line therapy in noncurative intent due to contraindication for PC (indication 3-I3). The median OS for patients treated with nivolumab was 5.8 months (95% CI: 4.5-7.3), and the 1-year OS was 28.4% (CI: 2.10-36.1). When patients with I3 were excluded to match inclusion criteria for CheckMate-141, median OS was 4.8 months (CI: 3.6-6.7) with 1-year OS of 21.8% (14.4-30.1). Patients with lower body surface area (BSA) (<1.81) had a median OS of 3.9 months (CI: 3.1-6.7) versus 9.0 months (CI: 6.5-14.8) in those with higher BSA, hazard ratio (HR)=0.12 (CI: 0.04-0.39, P <0.001). Patients receiving nivolumab for I1 had a median OS of 7.2 months (CI 3.8-9.8) versus 11.9 months (CI: 6.2-not reached) for I3, HR=1.73 (CI: 0.94-3.16). Patients receiving nivolumab for I2 had a median OS of 3.9 months (CI: 2.9-5.4) as compared with I3, HR=3.27 (CI: 1.80-5.94). Real-world analysis of patients with advanced/metastatic SCCHN in Ontario, Canada, treated with nivolumab demonstrates poorer median OS compared with CheckMate-141 trial. Lower BSA was a predictor of poorer median OS.

The relationship between the morningness-eveningness questionnaire and incident cancer: A historical clinical cohort study

OBJECTIVE

We conducted a retrospective cohort study to explore the relationship between chronotype measured by the total Morningness-Eveningness Questionnaire (MEQ) score and incident cancer.

METHODS

We used clinical and provincial health administrative data on consecutive adults who underwent a Level 1 Polysomnography (PSG) and completed the MEQ between 2010 and 2015 in an academic hospital (Ontario, Canada) and were cancer-free at baseline. Cancer status was derived from the Ontario Cancer Registry. Individuals were followed until death or March 31, 2020. We used multivariable Cox cause-specific regressions to address the research objective.

RESULTS

Of 3,004 individuals, 1,781 were analyzed: a median age of 54 years (IQR: 40-64) and 838 (47.1%) men. The median total MEQ score was 63 (IQR: 55-69); 61 (3.4%) were classified as evening (≤41), 536 (30.1%) as intermediate (42-58), and 1,184 (66.5%) as morning chronotypes (≥59). Over a median of 7 years (IQR: 5-8), 120 (6.7%) developed cancer. A U-shape relationship was found between the total MEQ score and an increased hazard of incident cancer, controlling for PSG measures of sleep apnea severity and sleep architecture, demographics, and comorbidities. Compared to the median of 63.0, a total MEQ score greater or less than the median was associated with an increased hazard of incident cancer, with the largest effect for those with a total score ≥76 (e.g., HR of a MEQ total score of 78 vs. 63: 2.01, 95% CI: 1.09-3.71).

CONCLUSION

The U-shaped curve may reflect deviations from a standard circadian tendency, which may stress biological systems and influence malignancy risk.

Non-fatal self-harm and suicide following postpartum psychiatric emergency department visits: A population-based retrospective cohort study

In a population-based cohort of postpartum individuals in Ontario, Canada, this study aimed to determine the risk of non-fatal self-harm and suicide within one year of an initial postpartum psychiatric emergency department (ED) visit (2008-2020), and the key associated factors. Of 16,475 postpartum individuals with psychiatric ED visits, 714 (4.3 %) had non-fatal self-harm within one year, and 23 (0.15 %) died by suicide. Risk was substantially higher for those with self-harm at the initial presentation. Further efforts to connect individuals with postpartum psychiatric ED visits with needed inpatient care and outpatient follow-up are required to reduce non-fatal self-harm and suicide risk.

Prevalence and Incidence Trends of Attention Deficit/Hyperactivity Disorder in Children and Youth Aged 1-24 Years in Ontario, Canada: A Validation Study of Health Administrative Data Algorithms: Tendances de la prévalence et de l'incidence du trouble de déficit de l'attention/hyperactivité chez les enfants et les jeunes âgés de 1 à 24 ans, en Ontario, Canada: une étude de validation des algorithmes de données administratives de santé

OBJECTIVE

To estimate prevalence and incidence rates over time in children and youth with attention deficit/hyperactivity disorder from the validation of population-based administrative data algorithms using family physicians' electronic medical records as a reference standard.

METHODS

A retrospective cohort study was conducted in Ontario, Canada to identify attention deficit/hyperactivity disorder among children and youth aged 1-24 years in health administrative data derived from case-finding algorithms using family physicians' electronic medical records. Multiple administrative data algorithms identifying attention deficit/hyperactivity disorder cases were developed and tested from physician-diagnosis of attention deficit/hyperactivity disorder in the electronic medical record to determine their diagnostic accuracy. We calculated algorithm performance using sensitivity, specificity, and predictive values. The most optimal algorithm was used to estimate prevalence and incidence rates of attention deficit/hyperactivity disorder from 2014 to 2021 in Ontario.

RESULTS

The optimal performing algorithm was "2 physician visits for attention deficit/hyperactivity disorder in 1 year or 1 attention deficit/hyperactivity disorder-specific prescription" with sensitivity: 83.2% (95% confidence interval [CI], 81.8% to 84.5%), specificity: 98.6% (95% CI, 98.5% to 98.7%), positive predictive value: 78.6% (95% CI, 77.1% to 80.0%) and negative predictive value: 98.9% (95% CI, 98.8% to 99.0%). From 2014, prevalence rates for attention deficit/hyperactivity disorder increased from 5.29 to 7.48 per 100 population in 2021 (N = 281,785). Males had higher prevalence rates (7.49 to 9.59 per 100 population, 1.3-fold increase) than females (2.96-5.26 per 100 population, 1.8-fold increase) from 2014 to 2021. Incidence rates increased from 2014 (0.53 per 100 population) until 2018, decreased in 2020 then rose steeply in 2021 (0.89 per 100 population, N = 34,013). Males also had higher incidence rates than females from 2014 to 2020 with females surpassing males in 2021 (0.70-0.81 per 100 male population,1.2-fold increase versus 0.36-0.97 per 100 female population, 2.7-fold increase).

CONCLUSIONS

Attention deficit/hyperactivity disorder is increasing in prevalence. We developed an administrative data algorithm that can reliably identify children and youth with attention deficit/hyperactivity disorder with good diagnostic accuracy.

Real-world hepatitis C prevalence and treatment uptake at opioid agonist therapy clinics in Ontario, Canada

Widespread screening for hepatitis C virus (HCV) is necessary for Canada to meet its HCV elimination goals by 2030. People who currently or previously injected drugs are at high risk for HCV. Opioid agonist therapy (OAT, such as methadone and buprenorphine) has been shown to help stabilize the lives of people who are opioid-dependent. The distribution of OAT in North America typically requires daily, weekly, or monthly clinic visits and presents an opportunity for engagement, screening and treatment for those at high-risk of HCV. In this study, HCV screening was conducted by staff at OAT clinics in Ontario from 2016 to 2020 and those with chronic infections were treated on-site with direct-acting antivirals. Point-of-care or dried blood spot (DBS) testing was used for antibodies, DBS or serum for HCV RNA and serum for HCV RNA at SVR12 (sustained virological response). Clinics screened 1954 people (mean age 40 years ±12, 63% male). Forty-five percent were antibody positive, of whom 64% were HCV RNA+. Eighty percent of those RNA+ set an appointment in which 99% attended. Ninety-six percent started treatment with 87% completing treatment. Sixty-eight percent of people who completed treatment submitted a sample for SVR12 testing of which 97% achieved a virological cure. Results suggest that HCV screening and treatment at OAT clinics is feasible, effective and warrants expansion. Data suggest strong treatment adherence due to high rates of SVR12 comparable with other OAT-based HCV treatment programs. The lack of SVR12 sampling could be addressed by either on-site phlebotomy or incentivizing SVR12 sampling.

Proportion of Life Spent in Canada and the Incidence of Multiple Sclerosis in Permanent Immigrants

BACKGROUND AND OBJECTIVES

While immigrants to high-income countries have a lower risk of multiple sclerosis (MS) compared with host populations, it is unknown whether this lower risk among immigrants increases over time. Our objective was to evaluate the association between proportion of life spent in Canada and the hazard of incident MS in Canadian immigrants.

METHODS

We conducted a population-based retrospective cohort study in Ontario, using linked health administrative databases. We followed immigrants, who arrived in Ontario between 1985 and 2003, from January 1, 2003, to December 31, 2016, to record incident MS using a validated algorithm based on hospital admission or outpatient visits. We derived proportion of life spent in Canada based on age at arrival and time since immigration obtained from linked immigration records. We used multivariable proportional hazard models, adjusting for demographics and comorbidities, to evaluate the association between proportion of life in Canada and the incidence of MS, where proportion of life was modelled using restricted cubic spline terms. We further evaluated the role of age at migration (15 or younger vs older than 15 years), sex, and immigration class in sensitivity analyses.

RESULTS

We included 1.5 million immigrants (49.9% female, mean age 35.9 [SD 14.2] years) who had spent a median of 20% (Q1-Q3 10%-30%) of their life in Canada. During a mean follow-up of 13.9 years (SD 1.0), 934 (0.44/100,000 person-years) were diagnosed with MS. Compared with the median, a higher risk of MS was observed at higher values of proportion of life spent (e.g., hazard ratio [70% vs 20% proportion of life] 1.38; 1.07-1.78). This association did not vary by sex (p(sex × proportion of life) = 0.70) or immigration class (p(immigration class × proportion of life) = 0.13). The results did not vary by age at migration but were statistically significant only at higher values of proportion of life for immigrants aged 15 years or younger at arrival.

DISCUSSION

The risk of incident MS in immigrants varied with the proportion of life spent in Canada, suggesting an acculturation effect on MS risk. Further work is required to understand environmental and sociocultural factors driving the observed association.

COVID-19 vaccine reactogenicity among participants enrolled in the GENCOV study

BACKGROUND

GENCOV is a prospective, observational cohort study of COVID-19-positive adults. Here, we characterize and compare side effects between COVID-19 vaccines and determine whether reactogenicity is exacerbated by prior SARS-CoV-2 infection.

METHODS

Participants were recruited across Ontario, Canada. Participant-reported demographic and COVID-19 vaccination data were collected using a questionnaire. Multivariable logistic regression was performed to assess whether vaccine manufacturer, type, and previous SARS-CoV-2 infection are associated with reactogenicity.

RESULTS

Responses were obtained from n = 554 participants. Tiredness and localized side effects were the most common reactions across vaccine doses. For most participants, side effects occurred and subsided within 1-2 days. Recipients of Moderna mRNA and AstraZeneca vector vaccines reported reactions more frequently compared to recipients of a Pfizer-BioNTech mRNA vaccine. Previous SARS-CoV-2 infection was independently associated with developing side effects.

CONCLUSIONS

We provide evidence of relatively mild and short-lived reactions reported by participants who have received approved COVID-19 vaccines.

Factors associated with plans for early retirement among Ontario family physicians during the COVID-19 pandemic: a cross-sectional study

BACKGROUND

Higher numbers of family physicians (FPs) stopped practicing or retired during the COVID-19 pandemic, worsening the family doctor shortage in Canada. Our study objective was to determine which factors were associated with FPs' plans to retire earlier during the COVID-19 pandemic.

METHODS

We administered two cross-sectional online surveys to Ontario FPs asking whether they were "planning to retire earlier" as a result of the pandemic during the first and third COVID-19 pandemic waves (Apr-Jun 2020 and Mar-Jul 2021). We used logistic regression to determine which factors were associated with early retirement planning, adjusting for age.

RESULTS

The age-adjusted proportion of FP respondents planning to retire earlier was 8.2% (of 393) in the first-wave and 20.5% (of 454) in the third-wave. Planning for earlier retirement during the third-wave was associated with age over 50 years (50-59 years odds ratio (OR) 5.37 (95% confidence interval (CI):2.33-12.31), 60 years and above OR 4.18 (95% CI: 1.90-10.23)), having difficulty handling increased non-clinical responsibilities (OR 2.95 (95% CI: 1.79-4.94)), feeling unsupported to work virtually (OR 1.96 (95% CI: 1.19-3.23)) or in-person (OR 2.70 (95% CI: 1.67-4.55)), feeling unable to provide good care (OR 1.82 (95% CI: 1.10-3.03)), feeling work was not valued (OR 1.92 (95% CI: 1.15-3.23)), feeling frightened of dealing with COVID-19 (OR 2.01 (95% CI: 1.19-3.38)), caring for an elderly relative (OR 2.36 (95% CI: 1.69-3.97)), having difficulty obtaining personal protective equipment (OR 2.00 (95% CI: 1.16-3.43)) or difficulty implementing infection control practices in clinic (OR 2.10 (95% CI: 1.12-3.89)).

CONCLUSIONS

Over 20% of Ontario FP respondents were considering retiring earlier by the third-wave of the COVID-19 pandemic. Supporting FPs in their clinical and non-clinical roles, such that they feel able to provide good care and that their work is valued, reducing non-clinical (e.g., administrative) responsibilities, dealing with pandemic-related fears, and supporting infection control practices and personal protective equipment acquisition in clinic, particularly in those aged 50 years or older may help increase family physician retention during future pandemics.

Can laboratory HIV and infectious syphilis data inform future pre-exposure prophylaxis use in women in Ontario, Canada?

OBJECTIVES

Infectious syphilis has been proposed as an indication for HIV pre-exposure prophylaxis (PrEP) in women. We explored how many women experienced HIV seroconversion after being diagnosed with syphilis in Ontario between 20 April 2010 and 31 December 2021.

METHODS

Through deterministic linkage of laboratory data at the Public Health Ontario laboratory, which conducts the vast majority of syphilis and HIV testing in Ontario, we quantified the number of females with positive syphilis diagnoses who subsequently exhibited HIV seroconversion between April 2010 and December 2021. New HIV cases were identified by diagnostic serology or HIV viral load test result of ≥20 copies/mL at least 60 days after the positive syphilis test. We report aggregate numbers of women with new laboratory evidence of HIV infection after their first positive syphilis test.

RESULTS

Among 7957 women with positive syphilis tests during the study period, 6554 (82.4%) had linkable HIV serology tests and 133 (1.7%) ever tested HIV positive. With further linkage to viral load data, the number of women who ever had laboratory evidence of HIV infection increased to 184 (2.3%). However, when restricting to women whose first positive HIV test or HIV viral load occurred after their first positive syphilis test, this number decreased to 34 (0.4%). The median (IQR) time between the positive syphilis test and the first laboratory evidence of HIV was 551 (IQR=226-1159) days.

CONCLUSION

Although it is clinically appropriate to recommend HIV PrEP to women with syphilis, Ontario surveillance data suggest that the population-level impact of this strategy on the HIV epidemic in Ontario would have been modest during this 11-year period. Future studies should explore additional ways of prioritising women for PrEP.

The impact of the COVID-19 pandemic on the use of restraint and seclusion interventions in Ontario emergency departments: A population-based study

While COVID-19 impacted all aspects of health care and patient treatment, particularly for patients with mental health/substance use (MH/SU) concerns, research has suggested a concerning increase in the use of restraint and seclusion (R/S) interventions, although results vary depending on facility type and patient population. Thus, the present study sought to explore COVID-related changes in the use of R/S interventions among patients presenting to Ontario emergency departments (EDs) with MH/SU complaints. To determine whether temporal and clinical factors were associated with changes in R/S use during COVID, binary logistic regression models were computed using data from the National Ambulatory Care Reporting System database. We then compared both prevalence rates and probability of an R/S event occurring during an ED visit in Ontario before and after the onset of COVID. The number of ED visits during which an R/S event occurred for patients presenting with MH/SU concerns increased by 9.5%, while their odds of an R/S event occurring during an ED visit increased by 23% in Ontario after COVID onset. Similarly, R/S event probability increased for patients presenting with MH/SU concerns after COVID onset (0.7% - 21.3% increase), particularly during the first wave, with the greatest increases observed for concerns associated with increased restraint risk pre-COVID. R/S intervention use increased substantially for patients presenting to Ontario EDs with MH/SU concerns during the first wave of COVID when the strain on healthcare system and uncertainty about the virus was arguably greatest. Patients with concerns already associated with increased R/S risk also showed the largest increases in R/S probability, suggesting increased behavioural issues during treatment among this population after COVID onset. These results have the potential to inform existing policies to mitigate risks associated with R/S intervention use during future public health emergencies and in general practice.

Population Trends of New Prescriptions for Antihyperglycemics and Antihypertensives Between 2014 and 2022

BACKGROUND

In the wake of pandemic-related health decline and health care disruptions, there are concerns that previous gains for cardiovascular risk factors may have stalled or reversed. Population-level excess burden of drug-treated diabetes and hypertension during the pandemic compared with baseline is not well characterized. We evaluated the change in incident prescription claims for antihyperglycemics and antihypertensives before versus during the pandemic.

METHODS AND RESULTS

In this retrospective, serial, cross-sectional, population-based study, we used interrupted time series analyses to examine changes in the age- and sex-standardized monthly rate of incident prescriptions for antihyperglycemics and antihypertensives in patients aged ≥66 years in Ontario, Canada, before the pandemic (April 2014 to March 2020) compared with during the pandemic (July 2020 to November 2022). Incident claim was defined as the first prescription filled for any medication in these classes. The characteristics of patients with incident prescriptions of antihyperglycemics (n=151 888) or antihypertensives (n=368 123) before the pandemic were comparable with their pandemic counterparts (antihyperglycemics, n=97 015; antihypertensives, n=146 524). Before the pandemic, monthly rates of incident prescriptions were decreasing (-0.03 per 10 000 individuals [95% CI, -0.04 to -0.01] for antihyperglycemics; -0.14 [95% CI, -0.18 to -0.10] for antihypertensives). After July 2020, monthly rates increased (postinterruption trend 0.31 per 10 000 individuals [95% CI, 0.28-0.34] for antihyperglycemics; 0.19 [95% CI, 0.14-0.23] for antihypertensives).

CONCLUSIONS

Population-level increases in new antihyperglycemic and antihypertensive prescriptions during the pandemic reversed prepandemic declines and were sustained for >2 years. Our findings are concerning for current and future cardiovascular health.

Risk of chronic obstructive pulmonary disease in a large cohort of Ontario, Canada workers

Although several occupational exposures have been linked to the risk of COPD; limited data exists on sex-specific differences. This study aimed to identify at-risk occupations and sex differences for COPD risk. Cases were identified in a large surveillance system established through the linkage of former compensation claimants' data (non-COPD claims) to physician visits, ambulatory care data, and hospital inpatient data (1983-2020). Cox proportional hazard models were used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CI) for occupation groups (occupation at time of claim), stratified by sex. HRs were indirectly adjusted for cigarette smoking using another population dataset. A total of 29,445 male and 14,693 female incident cases of COPD were identified. Increased risks were observed in both sexes for construction (HRmale 1.15, 95% CI 1.12-1.19; HRfemale 1.54, 95% CI 1.29-1.83) transport/equipment operating (HRmale 1.32, 95% CI 1.28-1.37; HRfemale 1.53, 95% CI 1.40-1.68) farming (HRmale 1.23, 95% CI 1.15-1.32; HRfemale 1.19, 95% CI 1.04-1.37) and janitors/cleaners (HRmale 1.31, 95% CI 1.24-1.37; HRfemale 1.40, 95% CI 1.31-1.49). Increased risks were observed for females employed as chefs and cooks (HR 1.44, 95% CI 1.31-1.58), bartenders (HR 1.38, 95% CI 1.05-1.81), and those working in food/beverage preparation (HR 1.34, 95% CI 1.24-1.45) among other occupations. This study demonstrates elevated risk of COPD among both male and female workers potentially exposed to vapours, gases, dusts, and fumes, highlighting the need for occupational surveillance of COPD.

Modeling chronic disease risk across equity factors using a population-based prediction model: the Chronic Disease Population Risk Tool (CDPoRT)

BACKGROUND

Predicting chronic disease incidence at a population level can help inform overall future chronic disease burden and opportunities for prevention. This study aimed to estimate the future burden of chronic disease in Ontario, Canada, using a population-level risk prediction algorithm and model interventions for equity-deserving groups who experience barriers to services and resources due to disadvantages and discrimination.

METHODS

The validated Chronic Disease Population Risk Tool (CDPoRT) estimates the 10-year risk and incidence of major chronic diseases. CDPoRT was applied to data from the 2017/2018 Canadian Community Health Survey to predict baseline 10-year chronic disease estimates to 2027/2028 in the adult population of Ontario, Canada, and among equity-deserving groups. CDPoRT was used to model prevention scenarios of 2% and 5% risk reductions over 10 years targeting high-risk equity-deserving groups.

RESULTS

Baseline chronic disease risk was highest among those with less than secondary school education (37.5%), severe food insecurity (19.5%), low income (21.2%) and extreme workplace stress (15.0%). CDPoRT predicted 1.42 million new chronic disease cases in Ontario from 2017/2018 to 2027/2028. Reducing chronic disease risk by 5% prevented 1500 cases among those with less than secondary school education, prevented 14 900 cases among those with low household income and prevented 2800 cases among food-insecure populations. Large reductions of 57 100 cases were found by applying a 5% risk reduction in individuals with quite a bit workplace stress.

CONCLUSION

Considerable reduction in chronic disease cases was predicted across equity-defined scenarios, suggesting the need for prevention strategies that consider upstream determinants affecting chronic disease risk.

Identifying 2SLGBTQ+ individuals experiencing homelessness using Point-in-Time counts: Evidence from the 2021 Toronto Street Needs Assessment survey

INTRODUCTION

The objective of this study was to utilize the data generated by the City of Toronto, Street Needs Assessment conducted in 2021 to explore the prevalence, causes, experiences, and characteristics of 2-spirit, lesbian, gay, bisexual, transgender, queer, and questioning (2SLGBTQ+) individuals experiencing homelessness in Toronto, Ontario, Canada.

METHODS

Data was collected by the City of Toronto during its Street Needs Assessment in April 2021. The Street Needs Assessment is a needs assessment survey and Point-in-Time count of people experiencing homelessness across the city of Toronto. Homelessness included any individual who was sleeping outdoors or staying in City-administered emergency/transitional shelters and shelter motels/hotels on the night of data collection. The Street Needs Assessment survey was administered to clients by trained shelter and outreach staff using a computer or mobile device. To ensure that survey questions were 2SLGBTQ+ inclusive, questions on sexual orientation, gender identity, and 2SLGBTQ+ identity were included in the survey.

RESULTS

Two hundred and eighty-eight 2SLGBTQ+ individuals completed the survey. Compared to non-2SLGBTQ+ individuals experiencing homelessness, 2SLGBTQ+ respondents were younger at the time of survey completion and when they first experienced homelessness, were more likely to have been in foster care or a group home, reported higher rates of conflict with and/or abuse by a parent/guardian as their main pathway into homelessness, and were more likely to experience chronic homelessness.

CONCLUSION

Our study results demonstrate that Street Needs Assessments and Point-in-Time counts can be used to examine homelessness in marginalized populations, including 2SLGBTQ+ individuals and that sexual orientation and gender identity questions need to be included on future government surveys. The consistency of findings from this study and previous research suggests that 2SLGBTQ+ individuals experience a significant need for population-based housing and social support services aimed at meeting the needs of 2SLGBTQ+ populations.

Characteristics of primary care practices by proportion of patients unvaccinated against SARS-CoV-2: a cross-sectional cohort study

BACKGROUND

Variations in primary care practices may explain some differences in health outcomes during the COVID-19 pandemic. We sought to evaluate the characteristics of primary care practices by the proportion of patients unvaccinated against SARS-CoV-2.

METHODS

We conducted a population-based, cross-sectional cohort study using linked administrative data sets in Ontario, Canada. We calculated the percentage of patients unvaccinated against SARS-CoV-2 enrolled with each comprehensive-care family physician, ranked physicians according to the proportion of patients unvaccinated, and identified physicians in the top 10% (v. the other 90%). We compared characteristics of family physicians and their patients in these 2 groups using standardized differences.

RESULTS

We analyzed 9060 family physicians with 10 837 909 enrolled patients. Family physicians with the largest proportion (top 10%) of unvaccinated patients (n = 906) were more likely to be male, to have trained outside of Canada, to be older, and to work in an enhanced fee-for-service model than those in the remaining 90%. Vaccine coverage (≥ 2 doses of SARS-CoV-2 vaccine) was 74% among patients of physicians with the largest proportion of unvaccinated patients, compared with 87% in the remaining patient population. Patients in the top 10% group tended to be younger and live in areas with higher levels of ethnic diversity and immigration and lower incomes.

INTERPRETATION

Primary care practices with the largest proportion of patients unvaccinated against SARS-CoV-2 served marginalized communities and were less likely to use team-based care models. These findings can guide resource planning and help tailor interventions to integrate public health priorities within primary care practices.

Cardiometabolic risk factors in social housing residents: A multi-site cross-sectional survey in older adults from Ontario, Canada

OBJECTIVE

This study describes cardiometabolic diseases and related risk factors in vulnerable older adults residing in social housing, aiming to inform primary care initiatives to reduce health inequities. Associations between sociodemographic variables, modifiable risk factors (clinical and behavioural), health-related quality of life and self-reported cardiometabolic diseases were investigated.

DESIGN, SETTING, AND PARTICIPANTS

This was a cross-sectional study with an interviewer-administered questionnaire. Data was collected from residents aged 55 years and older residing in 30 social housing apartment buildings in five regions in Ontario, Canada.

OUTCOME MEASURES

The proportion of cardiometabolic diseases and modifiable risk factors (e.g., clinical, behavioural, health status) in this population was calculated.

RESULTS

Questionnaires were completed with 1065 residents: mean age 72.4 years (SD = 8.87), 77.3% were female, 87.2% were white; 48.2% had less than high school education; 22.70% self-reported cardiovascular disease (CVD), 10.54% diabetes, 59.12% hypertension, 43.59% high cholesterol. These proportions were higher than the general population. Greater age was associated with overweight, high cholesterol, high blood pressure and CVD. Poor health-related quality of life was associated with self-reported CVD and diabetes.

CONCLUSIONS

Older adults residing in social housing in Ontario have higher proportion of cardiovascular disease and modifiable risk factors compared to the general population. This vulnerable population should be considered at high risk of cardiometabolic disease. Primary care interventions appropriate for this population should be implemented to reduce individual and societal burdens of cardiometabolic disease.

Fetal alcohol spectrum disorder diagnostic clinic capacity in Canadian Provinces and territories

This study investigated the diagnostic capacity for Fetal Alcohol Spectrum Disorder (FASD) in multidisciplinary clinics across several provincial and one territorial jurisdictions of Canada: Alberta, British Columbia, Manitoba, Ontario and Northwest Territories. The data were collected directly from clinics capable of providing diagnoses of FASD and examined annual capacity for the assessment and diagnosis of FASD per year from 2015 to 2019. In total, 58 FASD diagnostic clinics were identified and 33 clinics participated in this survey. The study identified inadequate FASD diagnostic capacity in all participating jurisdictions. Based on the findings and the current population sizes, it is estimated that 98% of individuals with FASD are undiagnosed or misdiagnosed in Canada. Wait times for FASD diagnosis ranged from 1 month to 4.5 years across participating jurisdictions. The annual FASD diagnostic capacity in the select provinces and territories require at least a 67-fold increase per year.

Survival, treatment patterns, and costs of HER2+ metastatic breast cancer patients in Ontario between 2005 to 2020

BACKGROUND

To enable the integration of novel therapies, it is critical to understand current long-term outcomes in HER2-positive metastatic breast cancer (mBC), including survival, treatment patterns, and costs. We sought to define these outcomes among patients with mBC in Ontario.

METHODS

We conducted a retrospective population-level study in Ontario women diagnosed with breast cancer of any stage between January 1, 2005 and December 31, 2019, with follow-up until December 31, 2020. HER2-positivity was based on receipt of a HER2-targeted therapy (HER2-TT) in the first line (1L) metastatic setting. Administrative databases at ICES were used to assess outcomes.

RESULTS

In Ontario, 2557 patients were diagnosed with mBC and received a HER2-TT, and of these 1606 were diagnosed with early-stage (stage I-III) that became metastatic (recurrent), while 951 were diagnosed with late stage/de novo mBC (stage IV). The average age of all patients was 54.8 years ± 12.7 years. Treatment regimens that included pertuzumab and trastuzumab (cohort name: pert_tras) were the most frequently used HER2-TT for 1L mBC (51.4%), while T-DM1 was the most frequent therapy (87.5%) in second line (2L). The median overall survival (mOS) from initiation of 1L pert_tras was not reached, whereas mOS from initiation of T-DM1 in 2L was 18.7 months. The overall mean cost per patient on pert_tras during 1L was $267,282. The main cost drivers were the cost of systemic therapy, followed by cancer clinic visits, with a mean cost per patient at $158,961 and $73,882, respectively.

CONCLUSION

The baseline characteristics and treatment patterns for patients who received HER2-TT in our study align with previously reported results. However, the mOS observed for 2L T-DM1 was shorter than that found in pivotal, clinical trial literature. As expected, anti-cancer systemic therapy costs were the main contributor to the over quarter-million dollar mean cost per patient on pert_tras in 1L.

High health care use prior to elective surgery for osteoarthritis is associated with poor postoperative outcomes: A Canadian population-based cohort study

BACKGROUND

The characterization and influence of preoperative health care use on quality-of-care indicators (e.g., readmissions) has received limited attention in populations with musculoskeletal disorders. The purpose of this study was to characterize preoperative health care use and examine its effect on quality-of-care indicators among patients undergoing elective surgery for osteoarthritis.

METHODS

Data on health care use for 124,750 patients with elective surgery for osteoarthritis in Ontario, Canada, from April 1, 2015 to March 31, 2018 were linked across health administrative databases. Using total health care use one-year previous to surgery, patients were grouped from low to very high users. We used Poisson regression models to estimate rate ratios, while examining the relationship between preoperative health care use and quality-of-care indicators (e.g., extended length of stay, complications, and 90-day hospital readmissions). We controlled for covariates (age, sex, neighborhood income, rural/urban residence, comorbidities, and surgical anatomical site).

RESULTS

We found a statistically significant trend of increasing worse outcomes by health care use gradients that persisted after controlling for patient demographics and comorbidities. Findings were consistent across surgical anatomical sites. Moreover, very high users have relatively large numbers of visits to non-musculoskeletal specialists.

CONCLUSIONS

Our findings highlight that information on patients' preoperative health care use, together with other risk factors (such as comorbidities), could help decision-making when benchmarking or reimbursing hospitals caring for complex patients undergoing surgery for osteoarthritis.

Prevalence of dementia among people experiencing homelessness in Ontario, Canada: a population-based comparative analysis

BACKGROUND

Cognitive decline in people experiencing homelessness is an increasingly recognised issue. We compared the prevalence of dementia among people experiencing homelessness to housed individuals in the general population and those living in low-income neighbourhoods.

METHODS

We conducted a population-based, cross-sectional, comparative analysis using linked health-care administrative data from Ontario, Canada. We included individuals aged 45 years or older on Jan 1, 2019, who visited hospital-based ambulatory care (eg, emergency department), were hospitalised, or visited a community health centre in 2019; and identified people experiencing homelessness if they had one or more health-care records with an indication of homelessness or unstable housing. Prevalence of dementia was ascertained as of Dec 31, 2019, using a validated case definition for Alzheimer's disease and related dementia that was modified to include diagnoses made at a community health centre. Poisson models were used to generate estimates of prevalence. Estimates were compared with Ontarians that accessed any of the same health-care services over the same time, overall (general population group), and among those who were in the lowest quintile of area-based neighbourhood income (low-income group).

FINDINGS

12 863 people experiencing homelessness, 475 544 people in the low-income comparator group, and 2 273 068 people in the general population comparator group were included in the study. Dementia prevalence was 68·7 per 1000 population among people experiencing homelessness, 62·6 per 1000 population in the low-income group, and 51·0 per 1000 population in the general population group. Descriptively, prevalence ratios between people experiencing homelessness and the comparator groups were highest within the ages of 55-64 years and 65-74 years in both sexes, ranging from 2·98 to 5·00. After adjusting for age, sex, geographical location of residence (urban vs rural), and health conditions associated with dementia, the prevalence ratio of dementia among people experiencing homelessness was 1·71 (95% CI 1·60-1·82) compared with the low-income group and 1·90 (1·79-2·03) compared with the general population group.

INTERPRETATION

People experiencing homelessness experience a high burden of dementia compared with housed populations in Ontario. Findings suggest that people experiencing homelessness might experience dementia at younger ages and could benefit from the development of proactive screening and housing interventions.

FUNDING

The Public Health Agency of Canada.

COVID-19 vaccination intention and vaccine hesitancy among citizens of the Métis Nation of Ontario

OBJECTIVE

The study objective is to measure the influence of psychological antecedents of vaccination on COVID-19 vaccine intention among citizens of the Métis Nation of Ontario (MNO).

METHODS

A population-based online survey was implemented by the MNO when COVID-19 vaccines were approved in Canada. Questions included vaccine intention, the short version of the "5C" psychological antecedents of vaccination scale (confidence, complacency, constraint, calculation, collective responsibility), and socio-demographics. Census sampling via the MNO Registry was used achieving a 39% response rate. Descriptive statistics, bivariate analyses, and multinomial logistic regression models (adjusted for sociodemographic variables) were used to analyze the survey data.

RESULTS

The majority of MNO citizens (70.2%) planned to be vaccinated. As compared with vaccine-hesitant individuals, respondents with vaccine intention were more confident in the safety of COVID-19 vaccines, believed that COVID-19 is severe, were willing to protect others from getting COVID-19, and would research the vaccines (Confident OR = 19.4, 95% CI 15.5-24.2; Complacency OR = 6.21, 95% CI 5.38-7.18; Collective responsibility OR = 9.83, 95% CI 8.24-11.72; Calculation OR = 1.43, 95% CI 1.28-1.59). Finally, respondents with vaccine intention were less likely to let everyday stress prevent them from getting COVID-19 vaccines (OR = 0.47, 95% CI 0.42-0.53) compared to vaccine-hesitant individuals.

CONCLUSION

This research contributes to the knowledge base for Métis health and supported the MNO's information sharing and educational activities during the COVID-19 vaccines rollout. Future research will examine the relationship between the 5Cs and actual uptake of COVID-19 vaccines among MNO citizens.

Breast (female), colorectal, and lung cancer survival in people with intellectual or developmental disabilities: A population-based retrospective cohort study

OBJECTIVES

Cancer is a leading cause of death among people living with intellectual or developmental disabilities (IDD). There is little empirical evidence documenting survival or comparing outcomes to those without IDD. This study investigated the association between IDD and cancer survival among adults with breast (female), colorectal, or lung cancer.

METHODS

A population-based retrospective cohort study was conducted in Ontario, Canada, with routinely collected data. Patients with breast, colorectal, or lung cancer were included (2007‒2019). IDD status before cancer was determined using an established administrative data algorithm. The outcomes of interest included death from any cause and death from cancer. Cox proportional hazards models and competing events analyses using multivariable cause-specific hazards regression were completed. Analyses were stratified by cancer type. Interactions with age, sex, and stage at diagnosis, as well as sensitivity analyses, were completed.

RESULTS

The final cohorts included 123,695 breast, 98,809 colorectal, and 116,232 lung cancer patients. Individuals with IDD experienced significantly worse survival than those without IDD. The adjusted hazard ratios of all-cause death were 2.74 (95% CI 2.41‒3.12), 2.42 (95% CI 2.18‒2.68), and 1.49 (95% CI 1.34‒1.66) times higher for breast, colorectal, and lung cancer patients with IDD relative to those without. These findings were consistent for cancer-specific deaths. With few exceptions, worse survival for people with IDD persisted regardless of stage at diagnosis.

CONCLUSION

People with IDD experienced worse cancer survival than those without IDD. Identifying and intervening on the factors and structures responsible for survival disparities is imperative.

An evaluation of an employment assistance program focused on people living with HIV in Toronto, Canada

Unemployment is more common among people living with HIV (PLWH) compared to the general population. PLWH who are employed have better physical and mental health outcomes compared to unemployed PLWH. The main objective of this mixed-methods study was to conduct a program evaluation of Employment Action (EACT), a community-based program that assists PLWH in Toronto, Ontario, Canada to maintain meaningful employment. We extracted quantitative data from two HIV services databases used by EACT, and collected qualitative data from 12 individuals who had been placed into paid employment through EACT. From 131 clients included in the analysis, 38.1% (n = 50) maintained their job for at least 6 weeks within the first year of enrollment in the EACT program. Gender, ethnicity, age, and first language did not predict employment maintenance. Our interviews highlighted the barriers and facilitators to effective service delivery. Key recommendations include implementing skills training, embedding PLWH as EACT staff, and following up with clients once they gain employment. Investment in social programs such as EACT are essential for strengthening their data collection capacity, active outreach to service users, and sufficient planning for the evaluation phase prior to program implementation.

First-line Palliative Chemotherapy for Colorectal Cancer: a Population-based Analysis of Delivery and Outcomes in a Single-payer Health System

AIMS

Clinical practice guidelines recommend palliative chemotherapy for most patients with metastatic colorectal cancer. However, outcomes observed in the real world compared with patients enrolled in clinical trials have not been sufficiently described. The objective of this study was to evaluate the delivery and outcomes of first-line palliative chemotherapy administered to patients with colorectal cancer in routine clinical practice compared with clinical trials.

MATERIALS AND METHODS

Using linked health administrative data, we carried out a retrospective population-level cohort study on patients diagnosed with colorectal cancer in Ontario, Canada from 2010 to 2019. Patient, disease and treatment characteristics were summarised. The primary outcome was median overall survival, stratified by treatment prescribed and age. Demographics and outcomes in this real-world population were compared with those from pivotal clinical trials. A multivariable Cox regression model reporting hazard ratios and 95% confidence intervals was used to determine factors associated with survival in patients receiving systemic treatment.

RESULTS

We identified 70 987 patients with a new diagnosis of colorectal cancer, of which 4613 received first-line chemotherapy for unresectable locally advanced or metastatic disease and formed the study cohort. Fifty-eight per cent were male and the mean age was 63 years. Most had colon cancer (69%), at least one comorbidity (73%) and lived in an urban location (79%). Less than half (47%) had surgery after diagnosis. The most common regimen prescribed was folinic acid, 5-fluorouracil and irinotecan (FOLFIRI) with bevacizumab or epidermal growth factor receptor inhibitors (EGFRi; n = 2784, 60%). Among all treated patients, the median overall survival was 17.1 months, with survival difference by regimen [median overall survival 18.3 for FOLFIRI with bevacizumab or EGFRi, 19.6 for folinic acid, 5-fluorouracil and oxaliplatin (FOLFOX)/capecitabine, oxaliplatin (XELOX) with bevacizumab or EGFRi, 13.6 for FOLFIRI alone and 7.8 for 5-fluorouracil or capecitabine]. Patients aged >80 years were most likely to have received single-agent 5-fluorouracil or capecitabine, and had inferior overall survival compared with their younger counterparts. Compared with pivotal clinical trials, patients in the real world had inferior overall survival outcomes despite similar demographic characteristics (including age and sex).

CONCLUSIONS

In this real-world population-based analysis of patients receiving first-line chemotherapy for unresectable locally advanced or metastatic colorectal cancer, survival outcomes were inferior to those reported in randomised trials despite similarities in age and sex. This information can be used when counselling patients in routine practice about expected outcomes.

Risk of Repeat Psychiatric Emergency Department Visits in the Postpartum Period: A Population-Based Retrospective Cohort Study

STUDY OBJECTIVE

Approximately 1 in 100 postpartum individuals visit an emergency department (ED) for a psychiatric reason. Repeat visits can signify problems with the quality of care received during or after the initial visit; this study aimed to understand risk for repeat postpartum psychiatric ED visits.

METHODS

This population-based cohort study used Ontario, Canada health administrative data available through ICES (formerly the Institute for Clinical Evaluative Sciences) to identify all individuals discharged from postpartum psychiatric ED visits (2008 to 2021) and measured the proportion with one or more repeat psychiatric ED visit within 30 days. Using modified Poisson regression, we calculated the association between one or more repeat visits and sociodemographic, medical, obstetric, infant, continuity of care, past service use, and index ED visit characteristics both overall and stratified by psychiatric diagnosis.

RESULTS

Of 14,100 individuals, 11.7% had one or more repeat psychiatric ED visits within 30 days. Repeat visit risk was highest for those with schizophrenia-spectrum disorders (28.2%, adjusted risk ratio 2.41; 95% confidence interval 1.88 to 3.08, versus 9.5% anxiety referent). Low (versus no) psychiatric care continuity, prior psychiatric ED visits and admissions, and initial visits within 90 days postpartum were also associated with increased risk, whereas intentional self-injury was associated with reduced risk. In diagnosis-stratified analyses, the factors most consistently associated with repeat ED visits were past psychiatric ED visits and admissions, and initial visits within 90 days postpartum.

CONCLUSIONS

Over 1 in 10 postpartum psychiatric ED visits are followed by a repeat visit within 30 days. Targeted approaches are needed across clinical populations to reduce repeat ED visits in this population with young infants.

The association between inpatient rehabilitation intensity and outcomes after stroke in Ontario, Canada

BACKGROUND

Several studies have demonstrated improved outcomes poststroke when higher intensity rehabilitation is provided. Canadian Stroke Best Practice Recommendations advise patients receive 180 min of therapy time per day; however, the exact amount required to reach benefit is unknown.

AIMS

The primary aim of this study was to determine the association between rehabilitation intensity (RI) and total Functional Independence Measure (FIM) Instrument change. Secondary aims included determining the association between RI and discharge location, 90-day home time, rehabilitation effectiveness, and motor and cognitive FIM change.

METHODS

A retrospective cohort study was conducted using available administrative databases of acute stroke patients discharged to inpatient rehabilitation facilities in Ontario, Canada, from January 2017 to December 2021. RI was defined as number of minutes per day of direct therapy by all providers divided by rehabilitation length of stay. The association between RI and the outcomes of interest were analyzed using regression models with restricted cubic splines.

RESULTS

A total of 12,770 individuals were included. Mean age of the sample was 72.6 years, 46.0% of individuals were female, and 87.6% had an ischemic stroke. Mean RI was 74.7 min (range: 5-162 min) per day. Increased RI was associated with an increase in mean FIM change. However, there was diminishing incremental increase after reaching 95 min/day. Increased RI was positively associated with motor and cognitive FIM change, rehabilitation effectiveness, 90-day home time, and discharge to preadmission setting. Higher RI was associated with a lower likelihood of discharge to long-term care.

CONCLUSIONS

None of the patients met the recommended RI of 180 min/day based on the Canadian Stroke Best Practice Recommendations. Despite this, higher intensity was associated with better outcomes. Given that most positive associations were observed with a RI ⩾95 min/day, this may be a more feasible target.

Intellectual and developmental disabilities in Ontario's criminal justice and forensic mental health systems: Using data to tell the story

BACKGROUND

International studies show that adults with intellectual and developmental disabilities (IDD) are disproportionately represented in the criminal justice and forensic mental health systems; however, it is difficult to capture their involvement across systems in any one jurisdiction.

AIMS

The current study aimed to estimate the prevalence of IDD across different parts of the criminal justice and forensic mental health systems in Ontario and to describe the demographic and clinical profiles of these individuals relative to their counterparts without IDD.

METHODS

This project utilised administrative data to identify and describe the demographic and clinical characteristics of adults with IDD and criminal justice or forensic involvement across four sectors: federal correctional facilities, provincial correctional facilities, forensic inpatient mental health care and community mental health programmes. Questions were driven by and results were contextualised by a project advisory group and people with lived experience from the different sectors studied, resulting in a series of recommendations.

RESULTS

Adults with IDD were over-represented in each of the four settings, ranging from 2.1% in federal corrections to 16.7% in forensic inpatient care. Between 20% (forensic inpatient) and 38.4% (provincial corrections) were under the age of 25 and between 34.5% (forensic inpatient) and 41.8% (provincial corrections) resided in the lowest income neighbourhoods. Medical complexity and rates of co-occurring mental health conditions were higher for people with IDD than those without IDD in federal and provincial corrections.

CONCLUSIONS

Establishing a population-based understanding of people with IDD within these sectors is an essential first step towards understanding and addressing service and care needs. Building on the perspectives of people who work in and use these systems, this paper concludes with intervention recommendations before, during and after justice involvement.

Long-term cognitive impairment after probable delirium in long-term care residents: A population-based retrospective cohort study

BACKGROUND

The impact of delirium on cognition has not been well-studied in long-term care (LTC) residents. This study examined changes in cognition 1 year after a probable delirium episode among LTC residents, compared to LTC residents without probable delirium. We also evaluated whether the relationship between probable delirium and cognitive change differed according to a diagnosis of dementia.

METHODS

We conducted a population-based retrospective cohort study using linked health administrative data. The study population included adults aged 65+ residing in LTC in Ontario, Canada and assessed via the Resident Assessment Instrument-Minimum Dataset between January 1, 2016 and December 31, 2018. Probable delirium was ascertained via the delirium Clinical Assessment Protocol on the index assessment. Cognition was measured quarterly using the Cognitive Performance Scale (range 0-6, higher values indicate greater impairment). Cognitive decline up to 1 year after index was evaluated using multivariable proportional odds regression models.

RESULTS

Of 92,005 LTC residents, 2816 (3.1%) had probable delirium at index. Residents with probable delirium had an increased odds of cognitive decline compared to those without probable delirium, with adjusted odds ratios of 1.64 (95% confidence interval [CI] 1.35-1.99), 1.56 (95% CI 1.34-1.85), 1.57 (95% CI 1.32-1.86) and 1.50 (95% CI 1.25-1.80) after 1-3, 4-6, 7-9, and 10-12 months of follow-up. Residents with probable delirium and a comorbid dementia diagnosis had the highest adjusted odds of cognitive decline (adjusted odds ratio 5.57, 95% CI 4.79-6.48) compared to those without probable delirium or dementia. Residents with probable delirium were also more likely to die within 1 year than those without probable delirium (52.5% vs. 23.4%).

CONCLUSIONS

Probable delirium is associated with increased mortality and worsened cognition in LTC residents that is sustained months after the probable delirium episode. Efforts to prevent delirium in this population may help limit these adverse effects.

Early life exposure to pollens and increased risks of childhood asthma: a prospective cohort study in Ontario children

Asthma is a disease characterised by wheeze, cough and shortness of breath, and constitutes the most prevalent chronic disease among children [1]. Various phenotypes have been specifically identified in the paediatric population, and include early transient wheeze, current wheeze/asthma, and mild or moderate asthma [2]. Lifestyle behaviours, genetics, maternal and paternal factors, and environment exposures have been identified as risk factors in the multifactorial aetiology of childhood asthma [3].

Increased exposure to tree canopy around the place of residence at birth prevented the risk of childhood asthma development, but this protective effect can be reduced when exposure to weed and tree pollen increases https://bit.ly/3Tboabo

Classification of traumatic life events and substance use among persons admitted to inpatient psychiatry in Ontario, Canada

BACKGROUND

Trauma is commonly overlooked or undiagnosed in clinical care settings. Undetected trauma has been associated with elevated substance use highlighting the need to prioritize identifying individuals with undetected trauma through common characteristics.

OBJECTIVE

The purpose of this study is to identify classifications of traumatic life experiences and substance use among persons admitted to inpatient psychiatry in Ontario and to identify covariates associated with classification membership.

STUDY DESIGN

A population-based retrospective cohort study was conducted using interRAI Mental Health (MH) assessment data. Individuals were included who experienced traumatic life events (N = 10,125), in Ontario, Canada between January 1, 2015, to December 31, 2019.

RESULTS

Eight latent classes were identified that ranged from low (i.e., Class 1: Interpersonal Issues, Without Substance use) to high (i.e., Class 8: Widespread Trauma, Alcohol & Cannabis Addiction) complexity patterns of traumatic life events and substance use indicators. Classifications with similar trauma profiles were differentiated by patterns of substance use. For example, individuals in Class 2: Safety & Relationship Issues, Without Substance use and Class 3: Safety & Relationship Issues, Alcohol & Cannabis both had many estimates centered around the experience of victimization (e.g., victim of sexual assault, victim of physical assault, victim of emotional abuse). Multinomial logistic regression models highlighted additional factors associated with classifications such as homelessness, where those who were homeless were 2.09-4.02 times more likely to be in Class 6: Widespread Trauma & Substance Addiction.

INTERPRETATION

Trauma exposures are complex and varied among persons in inpatient psychiatry and can be further differentiated by substance use patterns. These findings provide a population-based estimate of the trauma experiences of persons in inpatient settings in Ontario, Canada. Findings demonstrate the importance of using comprehensive assessment to support clinical decision making in relation to trauma and substance.

Association Between Anesthesiologist Sex and Patients' Postoperative Outcomes: A Population-based Cohort Study

OBJECTIVE

To examine the association of anesthesiologist sex on postoperative outcomes.

BACKGROUND

Differences in patient postoperative outcomes exist, depending on whether the primary surgeon is male or female, with better outcomes seen among patients treated by female surgeons. Whether the intraoperative anesthesiologist's sex is associated with differential postoperative patient outcomes is unknown.

METHODS

We performed a population-based, retrospective cohort study among adult patients undergoing one of 25 common elective or emergent surgical procedures from 2007 to 2019 in Ontario, Canada. We assessed the association between the sex of the intraoperative anesthesiologist and the primary end point of the adverse postoperative outcome, defined as death, readmission, or complication within 30 days after surgery, using generalized estimating equations.

RESULTS

Among 1,165,711 patients treated by 3006 surgeons and 1477 anesthesiologists, 311,822 (26.7%) received care from a female anesthesiologist and 853,889 (73.3%) from a male anesthesiologist. Overall, 10.8% of patients experienced one or more adverse postoperative outcomes, of whom 1.1% died. Multivariable adjusted rates of the composite primary end point were higher among patients treated by male anesthesiologists (10.6%) compared with female anesthesiologists (10.4%; adjusted odds ratio 1.02, 95% CI: 1.00-1.05, P =0.048).

CONCLUSIONS

We demonstrated a significant association between sex of the intraoperative anesthesiologist and patient short-term outcomes after surgery in a large cohort study. This study supports the growing literature of improved patient outcomes among female practitioners. The underlying mechanisms of why outcomes differ between male and female physicians remain elusive and require further in-depth study.

Trajectories of Health Care Contact Days for Patients With Stage IV Non-Small Cell Lung Cancer

Importance

Patients with stage IV non-small cell lung cancer (NSCLC) experience substantial morbidity and mortality. Contact days (ie, the number of days with health care contact outside the home) measure how much of a person's life is consumed by health care, yet little is known about patterns of contact days for patients with NSCLC.

Objective

To describe the trajectories of contact days in patients with stage IV NSCLC and how trajectories vary by receipt of cancer-directed treatment in routine practice.

Design, Setting, and Participants

A retrospective, population-based decedent cohort study was conducted in Ontario, Canada. Participants included adults aged 20 years or older who were diagnosed with stage IV NSCLC (January 1, 2014, to December 31, 2017) and died (January 1, 2014, to December 31, 2019); there was a maximum 2-year follow-up. Data analysis was conducted from February 22 to August 16, 2023.

Exposure

Systemic cancer-directed therapy (yes or no) and type of therapy (chemotherapy vs immunotherapy vs targeted therapy).

Main Outcomes and Measures

Contact days (days with health care contact, outpatient or institution-based, outside the home) were identified through administrative data. The weekly percentage of contact days and fitted models with cubic splines were quantified to describe trajectories from diagnosis until death.

Results

A total of 5785 decedents with stage IV NSCLC were included (median age, 70 [IQR 62-77] years; 3108 [53.7%] were male, and 1985 [34.3%] received systemic therapy). The median overall survival was 108 (IQR, 49-426) days, median contact days were 36 (IQR, 21-62), and the median percentage that were contact days was 33.3%. A median of 5 (IQR, 2-10) days were spent with specialty palliative care. Patients who did not receive systemic therapy had a median overall survival of 66 (IQR, 34-130) days and median contact days of 28 (IQR, 17-44), of which a median of 5 (IQR, 2-9) days were spent with specialty palliative care. Overall and for subgroups, normalized trajectories followed a U-shaped distribution: contact days were most frequent immediately after diagnosis and before death. Patients who received targeted therapy had the lowest contact day rate during the trough (10.6%; vs immunotherapy, 15.4%; vs chemotherapy, 17.7%).

Conclusions and Relevance

In this cohort study, decedents with stage IV NSCLC had a median survival in the order of 3.5 months and spent 1 in every 3 days alive interacting with the health care system outside the home. These results highlight the need to better support patients and care partners, benchmark appropriateness, and improve care delivery.

Sex-based trajectories of health system use in lonely and not lonely older people: A population-based cohort study

BACKGROUND

There is growing interest in understanding the care needs of lonely people but studies are limited and examine healthcare settings separately. We estimated and compared healthcare trajectories in lonely and not lonely older female and male respondents to a national health survey.

METHODS

We conducted a retrospective cohort study of community-dwelling, Ontario respondents (65+ years) to the 2008/2009 Canadian Community Health Survey-Healthy Aging. Respondents were classified at baseline as not lonely, moderately lonely, or severely lonely using the Three-Item Loneliness Scale and then linked with health administrative data to assess healthcare transitions over a 12 -year observation period. Annual risks of moving from the community to inpatient, long-stay home care, long-term care settings-and death-were estimated across loneliness levels using sex-stratified multistate models.

RESULTS

Of 2684 respondents (58.8% female sex; mean age 77 years [standard deviation: 8]), 635 (23.7%) experienced moderate loneliness and 420 (15.6%) severe loneliness. Fewer lonely respondents remained in the community with no transitions (not lonely, 20.3%; moderately lonely, 17.5%; and severely lonely, 12.6%). Annual transition risks from the community to home care and long-term care were higher in female respondents and increased with loneliness severity for both sexes (e.g., 2-year home care risk: 6.1% [95% CI 5.5-6.6], 8.4% [95% CI 7.4-9.5] and 9.4% [95% CI 8.2-10.9] in female respondents, and 3.5% [95% CI 3.1-3.9], 5.0% [95% CI 4.0-6.0], and 5.4% [95% CI 4.0-6.8] in male respondents; 5-year long-term care risk: 9.2% [95% CI 8.0-10.8], 11.1% [95% CI 9.3-13.6] and 12.2% [95% CI 9.9-15.3] [female], and 5.3% [95% CI 4.2-6.7], 9.1% [95% CI 6.8-12.5], and 10.9% [95% CI 7.9-16.3] [male]).

CONCLUSIONS

Lonely older female and male respondents were more likely to need home care and long-term care, with severely lonely female respondents having the highest probability of moving to these settings.

Factors that contributed to Ontario adults' mental health during the first 16 months of the COVID-19 pandemic: a decision tree analysis

The COVID-19 pandemic has negatively impacted the mental health of individuals globally. However, less is known about the characteristics that contributed to some people having mental health problems during the pandemic, while others did not. Mental health problems can be understood on a continuum, ranging from acute (e.g., depression following a stressful event) to severe (e.g., chronic conditions that disrupt everyday functioning). Therefore, the purpose of this article was to generate profiles of adults who were more or less at risk for the development of mental health problems, in general, during the first 16-months of the COVID-19 pandemic in Ontario, Canada. Data were collected via online surveys at two time points: April-July 2020 and July-August 2021; 2,188 adults (Mage = 43.15 years; SD = 8.82) participated. Surveys included a demographic questionnaire and four previously validated tools to measure participants' mental health, subjective wellbeing, physical activity and sedentary behaviour, and sleep. A decision tree was generated at each time point for those with mental health problems, and those with no mental health problems. Results showed that subjective wellbeing was the biggest contributor to mental health status. Characteristics associated with no mental health problems among adults included having good wellbeing, being a good sleeper (quantity, quality, and patterns of sleep), and being over the age of 42. Characteristics associated with mental health problems included having poor wellbeing and being a poor sleeper. Findings revealed that specific characteristics interacted to contribute to adults' mental health status during the first 16 months of the COVID-19 pandemic. Given that wellbeing was the biggest contributor to mental health, researchers should focus on targeting adults' wellbeing to improve their mental health during future health crises.

Association of hospital-based substance use supports on emergency department revisits: a retrospective cohort study in Sudbury, Canada from 2018 to 2022

BACKGROUND

This study compares emergency department (ED) revisits for patients receiving hospital-based substance-use support compared to those who did not receive specialized addiction services at Health Sciences North in Sudbury, Ontario, Canada.

METHODS

The study is a retrospective observational study using administrative data from all patients presenting with substance use disorder (SUD) at Health Sciences North from January 1, 2018, and August 31, 2022 with ICD-10 codes from the Discharge Abstract Database (DAD) and the National Ambulatory Care Database (NACRS). There were two interventions under study: addiction medicine consult services (AMCS group), and specialized addiction medicine unit (AMU group). The AMCS is a consult service offered for patients in the ED and those who are admitted to the hospital. The AMU is a specialized inpatient medical unit designed to offer addiction support to stabilize patients that operates under a harm-reduction philosophy. The primary outcome was all cause ED revisit within 30 days of the index ED or hospital visit. The secondary outcome was all observed ED revisits in the study period. Kaplan-Meier curves were used to measure the proportion of 30-day revisits by exposure group. Odds ratios and Hazard Ratios were calculated using logistic regression models with random effects and Cox-proportional hazard model respectively.

RESULTS

A total of 5,367 patients with 10,871 ED index visits, and 2,127 revisits between 2018 and 2022 are included in the study. 45% (2,340/5,367) of patient were not admitted to hospital. 30-day revisits were less likely among the intervention group: Addiction Medicine Consult Services (AMCS) in the ED significantly reduced the odds of revisits (OR 0.53, 95% CI 0.39-0.71, p < 0.01) and first revisits (OR 0.42, 95% CI 0.33-0.53, p < 0.01). The AMU group was associated with lower revisits odds (OR 0.80, 95% CI 0.66-0.98, p = 0.03). For every additional year of age, the odds of revisits slightly decreased (OR 0.99, 95% CI 0.98-1.00, p = 0.01) and males were found to have an increased risk compared to females (OR 1.50, 95% CI 1.35-1.67, p < 0.01).

INTERPRETATION

We observe statistically significant differences in ED revisits for patients receiving hospital-based substance-use support at Health Sciences North. Hospital-based substance-use supports could be applied to other hospitals to reduce 30-day revisits.

Evaluating methods for risk prediction of Covid-19 mortality in nursing home residents before and after vaccine availability: a retrospective cohort study

BACKGROUND

SARS-CoV-2 vaccines are effective in reducing hospitalization, COVID-19 symptoms, and COVID-19 mortality for nursing home (NH) residents. We sought to compare the accuracy of various machine learning models, examine changes to model performance, and identify resident characteristics that have the strongest associations with 30-day COVID-19 mortality, before and after vaccine availability.

METHODS

We conducted a population-based retrospective cohort study analyzing data from all NH facilities across Ontario, Canada. We included all residents diagnosed with SARS-CoV-2 and living in NHs between March 2020 and July 2021. We employed five machine learning algorithms to predict COVID-19 mortality, including logistic regression, LASSO regression, classification and regression trees (CART), random forests, and gradient boosted trees. The discriminative performance of the models was evaluated using the area under the receiver operating characteristic curve (AUC) for each model using 10-fold cross-validation. Model calibration was determined through evaluation of calibration slopes. Variable importance was calculated by repeatedly and randomly permutating the values of each predictor in the dataset and re-evaluating the model's performance.

RESULTS

A total of 14,977 NH residents and 20 resident characteristics were included in the model. The cross-validated AUCs were similar across algorithms and ranged from 0.64 to 0.67. Gradient boosted trees and logistic regression had an AUC of 0.67 pre- and post-vaccine availability. CART had the lowest discrimination ability with an AUC of 0.64 pre-vaccine availability, and 0.65 post-vaccine availability. The most influential resident characteristics, irrespective of vaccine availability, included advanced age (≥ 75 years), health instability, functional and cognitive status, sex (male), and polypharmacy.

CONCLUSIONS

The predictive accuracy and discrimination exhibited by all five examined machine learning algorithms were similar. Both logistic regression and gradient boosted trees exhibit comparable performance and display slight superiority over other machine learning algorithms. We observed consistent model performance both before and after vaccine availability. The influence of resident characteristics on COVID-19 mortality remained consistent across time periods, suggesting that changes to pre-vaccination screening practices for high-risk individuals are effective in the post-vaccination era.

The Association of Frequency of Worry About Financial Debt With Substance Use Among Adults in Ontario, Canada

BACKGROUND

Financial debt and associated stress might increase the risk of substance use problems or exacerbate existing ones. Little evidence is available about the degree of debt stress and its association with substance use. The objective of this study was to examine the associations of the frequency of worry about debt with heavy episodic drinking (HED), daily smoking, e-cigarette use, and cannabis use in the past 30 days.

METHODS

Data were utilized from the 2020/2022 Monitor study, a repeated cross-sectional survey of adults 18 years and older in Ontario, Canada. The surveys employed a web-based panel survey of 6038 adults and collected data on debt-related stress, HED, tobacco smoking, e-cigarettes, and cannabis use in the past 30 days. Odds ratios (OR) were estimated from logistic regression models accounting for sociodemographic factors.

RESULTS

Overall, 18.4% of respondents reported that they were worried about their debt most or all of the time. Accounting for household income, educational status, employment status, and other factors, the results revealed that there was a dose-response relationship between the frequency of worry about debt and substance use including daily smoking, e-cigarette use, and cannabis use in the past 30 days compared to those who were not worried at all about their debt. Sex differences were also found in the association between worry about debt and e-cigarette use.

CONCLUSIONS

The frequency of worry about debt might have an important role in substance use, which suggests that financial well-being is vital in substance use prevention and harm reduction.

Knowledge, protective behaviours, and perception of Lyme disease in an area of emerging risk: results from a cross-sectional survey of adults in Ottawa, Ontario

BACKGROUND

The number of Lyme disease risk areas in Canada is growing. In regions with emerging tick populations, it is important to emphasize peridomestic risk and the importance of protective behaviours in local public health communication. This study aims to identify characteristics associated with high levels of Lyme disease knowledge and adoption of protective behaviours among residents in the Ottawa, Ontario region.

METHODS

A geographically stratified web survey was conducted in November 2020 (n = 2018) to determine knowledge, attitudes, and practices regarding Lyme disease among adult residents. Responses were used to calculate: (i) composite scores for knowledge and adoption of protective practices; and (ii) an exposure risk index based on reported activity in woodlands during the spring-to-fall tick exposure risk period.

RESULTS

60% of respondents had a high knowledge of Lyme disease, yet only 14% indicated they often use five or more measures to protect themselves. Factors strongly associated with a high level of Lyme disease knowledge included being 55 or older (Odds Ratio (OR) = 2.04), living on a property with a yard (OR = 3.22), having a high exposure index (OR = 1.59), and knowing someone previously infected with Lyme disease (OR = 2.05). Strong associations with the adoption of a high number of protective behaviours were observed with membership in a non-Indigenous racialized group (OR = 1.70), living on a property with a yard (OR = 2.37), previous infection with Lyme disease (OR = 2.13), prior tick bite exposure (OR = 1.62), and primarily occupational activity in wooded areas (OR = 2.31).

CONCLUSIONS

This study highlights the dynamics between Lyme disease knowledge, patterns of exposure risk awareness, and vigilance of personal protection in a Canadian region with emerging Lyme disease risk. Notably, this study identified gaps between perceived local risk and protective behaviours, presenting opportunities for targeted enhanced communication efforts in areas of Lyme disease emergence.

Socio-demographic determinants of COVID-19 vaccine uptake in Ontario: Exploring differences across the Health Region model

The COVID-19 pandemic continues to be a worldwide public health concern. Although vaccines against this disease were rapidly developed, vaccination uptake has not been equal across all the segments of the population, particularly in the case of underrepresented groups. However, there are also differences in vaccination across geographical areas, which might be important to consider in the development of future public health vaccination policies. In this study, we examined the relationship between vaccination status (having received the first dose of a COVID-19 vaccine), socio-economic strata, and the Health Regions for individuals in Ontario, Canada. Our results show that between October of 2021 and January of 2022, individuals from underrepresented communities were three times less likely to be vaccinated than White/Caucasian individuals across the province of Ontario, and that in some cases, within these groups, individuals in low-income brackets had significantly higher odds of vaccination when compared to their peers in high income brackets. Finally, we identified significantly lower odds of vaccination in the Central, East and West Health Regions of Ontario within certain underrepresented groups. This study shows that there is an ongoing need to better understand and address differences in vaccination uptake across diverse segments of the population of Ontario that the pandemic has largely impacted.

What are the views of Quebec and Ontario citizens on the tiebreaker criteria for prioritizing access to adult critical care in the extreme context of a COVID-19 pandemic?

BACKGROUND

The prioritization protocols for accessing adult critical care in the extreme pandemic context contain tiebreaker criteria to facilitate decision-making in the allocation of resources between patients with a similar survival prognosis. Besides being controversial, little is known about the public acceptability of these tiebreakers. In order to better understand the public opinion, Quebec and Ontario's protocols were presented to the public in a democratic deliberation during the summer of 2022.

OBJECTIVES

(1) To explore the perspectives of Quebec and Ontario citizens regarding tiebreakers, identifying the most acceptable ones and their underlying values. (2) To analyze these results considering other public consultations held during the pandemic on these criteria.

METHODS

This was an exploratory qualitative study. The design involved an online democratic deliberation that took place over two days, simultaneously in Quebec and Ontario. Public participants were selected from a community sample which excluded healthcare workers. Participants were first presented the essential components of prioritization protocols and their related issues (training session day 1). They subsequently deliberated on the acceptability of these criteria (deliberation session day 2). The deliberation was then subject to thematic analysis.

RESULTS

A total of 47 participants from the provinces of Quebec (n = 20) and Ontario (n = 27) took part in the online deliberation. A diverse audience participated excluding members of the healthcare workforce. Four themes were identified: (1) Priority to young patients - the life cycle - a preferred tiebreaker; (2) Randomization - a tiebreaker of last resort; (3) Multiplier effect of most exposed healthcare workers - a median acceptability tiebreaker, and (4) Social value - a less acceptable tiebreaker.

CONCLUSION

Life cycle was the preferred tiebreaker as this criterion respects intergenerational equity, which was considered relevant when allocating scarce resources to adult patients in a context of extreme pandemic. Priority to young patients is in line with other consultations conducted around the world. Additional studies are needed to further investigate the public acceptability of tiebreaker criteria.

Defining a low-risk birth cohort: a cohort study comparing two perinatal data sets in Ontario, Canada

Introduction

There are two main data sources for perinatal data in Ontario, Canada: the BORN BIS and CIHI-DAD. Such databases are used for perinatal health surveillance and research, and to guide health care related decisions.

Objectives

Our primary objective was to examine the level of agreement between the BIS and CIHI-DAD. Our secondary objectives were to identify the differences between the data sources when identifying a low-risk birth (LRB) cohort and to understand their implications.

Methods

We conducted a population-based cohort study comparing characteristics and clinical outcomes of all linkable births in BIS and CIHI-DAD between 1st April 2012 and 31st March 2018. We excluded out-of-hospital births, those with invalid healthcare numbers, non-Ontario residents and gestational age <20 weeks. We compared the portion of the cohort that met the criteria of a provincial definition of LRB based on each data source and compared clinical outcomes between the groups.

Results

During the study period, 779,979 eligible births were linkable between the two data sources. After applying the LRB exclusions, there were 129,908 cases in the BIS and 136,184 cases in CIHI-DAD. Most exclusion criteria had almost perfect, substantial or moderate agreement. The agreement for non-cephalic presentation and BMI ≥ 40 kg/m2 (kappa coefficients 0.409 and 0.256, respectively) was fair. Comparison between the two LRB cohorts identified differences in the prevalence of cesarean (14.3% BIS versus 12.0% CIHI-DAD) and NICU admission (8.7% BIS versus 7.5% CIHI-DAD) and only 0.01% difference in the prevalence of ICU admission.

Conclusions

Overall, we found high levels of agreement between the BIS and CIHI-DAD. Identifying a LRB cohort in either database may be appropriate, with the caveat of appropriate understanding of the collection, coding and definition of certain outcomes. The decision for selecting a database may depend on which variables are most important in a particular analysis.

A qualitative examination of primary care team's participation in the distribution of the COVID-19 vaccination

BACKGROUND

Primary health care (PHC) has historically led and implemented successful immunization programs, driven by strong relationships with patients and communities. During the COVID-19 pandemic, Canada began its vaccination strategy with mass immunizations that later included local efforts with PHC providers. This study seeks to understand how PHC contributed to the different phases of the COVID-19 vaccination rollouts in Ontario, Canada's most populous province.

METHODS

We conducted a descriptive qualitative study with focus groups consisting of PHC providers, administrators, and staff in Ontario. Eight focus groups were held with 39 participants representing geographic diversity across the six Ontario Health regions. Participants reflected a diverse range of clinical, administrative, and leadership roles. Each focus group was audio-recorded and transcribed with transcriptions analyzed using thematic analysis.

RESULTS

With respect to understanding PHC teams' participation in the different phases of the COVID-19 vaccination rollouts, we identified five themes: (i) supporting long-term care, (ii) providing leadership in mass vaccinations, (iii) integrating vaccinations in PHC practice sites, (iv) reaching those in need through outreach activities; and (v) PHC's contributions being under-recognized.

CONCLUSIONS

PHC was instrumental in supporting COVID-19 vaccinations in Ontario, Canada across all phases of the rollout. The flexibility and adaptability of PHC allowed teams to participate in both large-scale and small-scale vaccination efforts.

A cohort study of patients hospitalised with SARS-CoV-2 infection in Ontario: patient characteristics and outcomes by wave

INTRODUCTION

Each wave of the COVID-19 pandemic exhibited a unique combination of epidemiological, social and structural characteristics. We explore similarities and differences in wave-over-wave characteristics of patients hospitalised with COVID-19.

METHODS

This was a population-based study in Ontario province, Canada. Patients hospitalised with SARS-CoV-2 between 26 February 2020 and 31 March 2022 were included. An admission was considered related to SARS-CoV-2 infection if the provincial inpatient or outpatient hospital databases contained the ICD-10 diagnostic codes U071/U072 or the Ontario Laboratories Information System indicated a positive SARS-CoV-2 test result (PCR or rapid antigen testing) during the admission or up to two weeks prior. The primary outcome was 90-day mortality (modified Poisson regression). Secondary outcomes were use of critical care during the admission (logistic regression) and total length-of-stay (linear regression with heteroskedastic-consistent standard-error estimators). All models were adjusted for demographic characteristics, neighbourhood socioeconomic factors and indicators of illness severity.

RESULTS

There were 73,201 SARS-CoV-2-related admissions: 6127 (8%) during wave 1 (wild-type), 14,371 (20%) during wave 2 (wild-type), 16,653 (23%) during wave 3 (Alpha), 5678 (8%) during wave 4 (Delta) and 30,372 (42%) during wave 5 (Omicron). SARS-CoV-2 was the most responsible diagnosis for 70% of admissions during waves 1-2 and 42% in wave 5. The proportion of admitted patients who were long-term care residents was 18% (n = 1111) during wave 1, decreasing to 10% (n = 1468) in wave 2 and <5% in subsequent waves. During waves 1-3, 46% of all admitted patients resided in a neighbourhood assigned to the highest ethnic diversity quintile, which declined to 27% during waves 4-5. Compared to wave 1, 90-day mortality was similar during wave 2 (adjusted risk ratio [aRR]: 1.00 [95% CI: 0.95-1.04]), but lower during wave 3 (aRR: 0.89 [0.85-0.94]), wave 4 (aRR: 0.85 [0.79-0.91]) and wave 5 (aRR: 0.83 [0.80-0.88]). Improvements in survival over waves were observed among elderly patients (p-interaction <0.0001). Critical care admission was significantly less likely during wave 5 than previous waves (adjusted odds ratio: 0.50 [0.47-0.54]). The length of stay was a median of 8.5 (3.6-23.8) days during wave 1 and 5.3 (2.2-12.6) during wave 5. After adjustment, the mean length of stay was on average -10.4 (-11.1 to -9.8) days, i.e. shorter, in wave 5 vs wave 1.

CONCLUSION

Throughout the pandemic, sociodemographic characteristics of patients hospitalised with SARS-CoV-2 changed over time, particularly in terms of ethnic diversity, but still disproportionately affected patients from more marginalised regions. Improved survival and reduced use of critical care during the Omicron wave are reassuring.

Longitudinal adherence to surveillance for late effects of cancer treatment: a population-based study of adult survivors of childhood cancer

BACKGROUND

Adult survivors of childhood cancer are at elevated risk of morbidity and mortality compared to the general population, but their adherence to lifelong periodic surveillance is suboptimal. We aimed to examine adherence to surveillance guidelines for high-yield tests and identify risk factors for nonadherence in adult survivors of childhood cancer.

METHODS

In this retrospective, population-based cohort study, we used health care administrative data from Ontario, Canada, to identify adult survivors of childhood cancer diagnosed between 1986 and 2014 who were at elevated risk of therapy-related colorectal cancer, breast cancer, or cardiomyopathy. Using a Poisson regression framework, we assessed longitudinal adherence and predictors of adherence to the Children's Oncology Group surveillance guideline.

RESULTS

Among 3241 survivors, 327 (10%), 234 (7%), and 3205 (99%) were at elevated risk for colorectal cancer, breast cancer, and cardiomyopathy, respectively. Within these cohorts, only 13%, 6%, and 53% were adherent to recommended surveillance as of February 2020. During a median follow-up of 7.8 years, the proportion of time spent adherent was 14% among survivors at elevated risk for colorectal cancer, 10% for breast cancer, and 43% for cardiomyopathy. Significant predictors of adherence varied across the risk groups, but higher comorbidity was associated with adherence to recommended surveillance.

INTERPRETATION

Survivors of childhood cancer in Ontario are rarely up to date for recommended surveillance tests. Tailored interventions beyond specialized clinics are needed to improve surveillance adherence.

Attending physicians' annual service volume and use of virtual end-of-life care: A population-based cohort study in Ontario, Canada

IMPORTANCE

Physicians and their practice behaviors influence access to healthcare and may represent potentially modifiable targets for practice-changing interventions. Use of virtual care at the end-of-life significantly increased during the COVID-19 pandemic, but its association with physician practice behaviors, (e.g., annual service volume) is unknown.

OBJECTIVE

Measure the association of physicians' annual service volume with their use of virtual end-of-life care (EOLC) and the magnitude of physician-attributable variation in its use, before and during the pandemic.

DESIGN, SETTING AND PARTICIPANTS

Population-based cohort study using administrative data of all physicians in Ontario, Canada who cared for adults in the last 90 days of life between 01/25/2018-12/31/2021. Multivariable modified Poisson regression models measured the association between attending physicians' use of virtual EOLC and their annual service volume. We calculated the variance partition coefficients for each regression and stratified by time period before and during the pandemic.

EXPOSURE

Annual service volume of a person's attending physician in the preceding year.

MAIN OUTCOMES AND MEASURES

Delivery of ≥1 virtual EOLC visit by a person's attending physician and the proportion of variation in its use attributable to physicians.

RESULTS

Among the 35,825 unique attending physicians caring for 315,494 adults, use of virtual EOLC was associated with receiving care from a high compared to low service volume attending physician; the magnitude of this association diminished during the pandemic (adjusted RR 1.25 [95% CI 1.14, 1.37] pre-pandemic;1.10 (95% CI 1.08, 1.12) during the pandemic). Physicians accounted for 36% of the variation in virtual EOLC use pre-pandemic and 12% of this variation during the pandemic.

CONCLUSIONS AND RELEVANCE

Physicians' annual service volume was associated with use of virtual EOLC and physicians accounted for a substantial proportion of the variation in its use. Physicians may be appropriate and potentially modifiable targets for interventions to modulate use of EOLC delivery.

The safety of seasonal influenza vaccination among adults prescribed immune checkpoint inhibitors: A self-controlled case series study using administrative data

BACKGROUND

Immune checkpoint inhibitor (ICI) therapy for patients undergoing cancer treatment carries a risk of severe immune-related adverse events (IRAEs). Questions remain about whether seasonal influenza vaccination might increase the risk of developing IRAEs among these patients given that vaccines are immunomodulatory. Previous vaccine safety studies on patients with cancer prescribed ICI therapy have demonstrated conflicting results.

METHODS

Using health administrative data from Ontario, Canada among adults diagnosed with cancer who had been prescribed ICI therapy and who had received an influenza vaccine from 2012 to 2019, we conducted a self-controlled case series study. The pre-vaccination control period started 42-days post-ICI initiation until 14-days prior to vaccination, the risk period was 1-42 days post-vaccination, and the post-vaccination control period was after the risk period until ICI discontinuation or a maximum period of two years. Emergency department (ED) visit(s) and/or hospitalization for any cause after ICI initiation was used to identify severe IRAEs. We fitted a fixed-effects Poisson regression model accounting for seasonality and calendar time to estimate relative incidence of IRAEs between risk and control periods.

RESULTS

We identified 1133 records of cancer patients who received influenza vaccination while prescribed ICI therapy. Most were aged ≥ 66 years (73 %), were male (63 %), had lung cancer (54 %), and had received ICI therapy with a programmed cell death protein 1(PD-1) inhibitor (91 %). A quarter (26 %) experienced an ED visit and/or hospitalization during the observation period. Rates of ED visits and/or hospitalizations in the risk vs. control periods were similar, with an incidence rate ratio of 1.04 (95 % CI: 0.75-1.45). Subgroup and sensitivity analyses yielded similar results.

CONCLUSION

Seasonal influenza vaccination was not associated with an increased incidence of ED visit or hospitalization among adults with cancer treated with ICI therapy and our results support further evidence of vaccine safety.