Incidence of Total Knee Arthroplasty After Arthroscopic Surgery for Knee Osteoarthritis: A Secondary Analysis of a Randomized Clinical Trial.

Importance: It is unclear whether arthroscopic resection of degenerative knee tissues among patients with osteoarthritis (OA) of the knee delays or hastens total knee arthroplasty (TKA); opposite findings have been reported. Objective: To compare the long-term incidence of TKA in patients with OA of the knee after nonoperative management with or without additional arthroscopic surgery. Design, Setting, and Participants: In this ad hoc secondary analysis of a single-center, assessor-blinded randomized clinical trial performed from January 1, 1999, to August 31, 2007, 178 patients were followed up through March 31, 2019. Participants included adults diagnosed with OA of the knee referred for potential arthroscopic surgery in a tertiary care center specializing in orthopedics in London, Ontario, Canada. All participants from the original randomized clinical trial were included. Data were analyzed from June 1, 2021, to October 20, 2022. Exposures: Arthroscopic surgery (resection or debridement of degenerative tears of the menisci, fragments of articular cartilage, or chondral flaps and osteophytes that prevented full extension) plus nonoperative management (physical therapy plus medications as required) compared with nonoperative management only (control). Main Outcomes and Measures: Total knee arthroplasty was identified by linking the randomized trial data with prospectively collected Canadian health administrative datasets where participants were followed up for a maximum of 20 years. Multivariable Cox proportional hazards regression models were used to compare the incidence of TKA between intervention groups. Results: A total of 178 of 277 eligible patients (64.3%; 112 [62.9%] female; mean [SD] age, 59.0 [10.0] years) were included. The mean (SD) body mass index was 31.0 (6.5). With a median follow-up of 13.8 (IQR, 8.4-16.8) years, 31 of 92 patients (33.7%) in the arthroscopic surgery group vs 36 of 86 (41.9%) in the control group underwent TKA (adjusted hazard ratio [HR], 0.85 [95% CI, 0.52-1.40]). Results were similar when accounting for crossovers to arthroscopic surgery (13 of 86 [15.1%]) during follow-up (HR, 0.88 [95% CI, 0.53-1.44]). Within 5 years, the cumulative incidence was 10.2% vs 9.3% in the arthroscopic surgery group and control group, respectively (time-stratified HR for 0-5 years, 1.06 [95% CI, 0.41-2.75]); within 10 years, the cumulative incidence was 23.3% vs 21.4%, respectively (time-stratified HR for 5-10 years, 1.06 [95% CI, 0.45-2.51]). Sensitivity analyses yielded consistent results. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial of arthroscopic surgery for patients with OA of the knee, a statistically significant association with delaying or hastening TKA was not identified. Approximately 80% of patients did not undergo TKA within 10 years of nonoperative management with or without additional knee arthroscopic surgery. Trial Registration: ClinicalTrials.gov Identifier: NCT00158431.

Trends in emergency department visits during cold weather seasons among patients experiencing homelessness in Ontario, Canada: a retrospective population-based cohort study.

PURPOSE: Recent anecdotal reports suggest increasing numbers of people experiencing homelessness are visiting emergency departments (EDs) during cold weather seasons due to inadequate shelter availability. We examined monthly ED visits among patients experiencing homelessness to determine whether there has been a significant increase in such visits in 2022/2023 compared to prior years. METHODS: We used linked health administrative data to identify cohorts experiencing homelessness in Ontario between October and March of the 2018/2019 to 2022/2023 years. We analyzed the monthly rate of non-urgent ED visits as a proxy measure of visits plausibly attributable to avoidance of cold exposure, examining rates among patients experiencing homelessness compared to housed patients. We excluded visits for overdose or COVID-19. We assessed level and significance of change in the 2022/2023 year as compared to previous cold weather seasons using Poisson regression. RESULTS: We identified a total of 21,588 non-urgent ED visits across the observation period among patients experiencing homelessness in Ontario. Non-urgent ED visits increased 27% (RR 1.24 [95% CI 1.14-1.34]) in 2022/2023 compared to previous cold weather seasons. In Toronto, such visits increased by 70% (RR 1.68 [95% CI 1.57-1.80]). Among housed patients, non-urgent ED visits did not change significantly during this time period. CONCLUSION: Rates of ED visits plausibly attributable to avoidance of cold exposure by individuals experiencing homelessness increased significantly in Ontario in 2022/2023, most notably in Toronto. This increase in ED visits may be related to inadequate access to emergency shelter beds and warming services in the community.

RéSUMé: OBJECTIFS: Des rapports anecdotiques récents suggèrent qu'un nombre croissant de personnes en situation d'itinérance visitent les services d'urgence (SU) pendant les saisons froides en raison de la disponibilité insuffisante d'hébergement d'urgence. Nous avons examiné les visites mensuelles aux urgences chez les personnes en situation d'itinérance afin de déterminer s'il y a eu une augmentation significative de ces visites en 2022-2023 par rapport aux années précédentes. MéTHODES: Nous avons utilisé des données administratives de santé liées pour identifier les cohortes de personnes en situation d'itinérance en Ontario entre octobre et mars des années 2018/2019 à 2022/2023. Nous avons analysé le taux mensuel de visites aux urgences non urgentes comme mesure approximative des visites vraisemblablement attribuables à l'évitement de l'exposition au froid, en examinant les taux chez les personnes en situation d'itinérance par rapport aux patients logés. Nous avons exclu les visites pour surdose ou COVID-19. Nous avons évalué le niveau et l'importance du changement dans l'année 2022/2023 par rapport aux saisons froides précédentes en utilisant la régression de Poisson. RéSULTATS: Nous avons recensé un total de 21 588 visites non urgentes aux urgences au cours de la période d'observation chez des personnes en situation d'itinérance en Ontario. Les visites aux urgences non urgentes ont augmenté de 27 % (RR 1,24 [IC à 95 % 1,14-1,34]) en 2022­2023 par rapport aux saisons froides précédentes. À Toronto, ces visites ont augmenté de 70 % (RR 1,68 [IC à 95 % 1,57-1,80]). Parmi les patients logés, les visites aux urgences non urgentes n'ont pas changé de façon significative pendant cette période. CONCLUSIONS: Les taux de visites aux urgences attribuables vraisemblablement à l'évitement de l'exposition au froid par les personnes en situation d'itinérance ont augmenté considérablement en Ontario en 2022­2023, surtout à Toronto. Cette augmentation du nombre de visites aux urgences peut être liée à un accès inadéquat aux lits des refuges d'urgence et aux services de réchauffement dans la collectivité.

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.

Impact of non-medical cannabis legalization with market restrictions on health service use and incident cases of psychotic disorder in Ontario, Canada.

BACKGROUND: Cannabis is a risk factor in the onset and persistence of psychotic disorders. There is concern that non-medical cannabis legalization in Canada may have population-level impacts on psychotic disorders. We sought to examine changes in health service use and incident cases of psychotic disorder following cannabis legalization, during a period of tight restrictions on retail stores and product types. METHODS: We conducted a cross-sectional interrupted time-series analysis using linked population-based health administrative data from Ontario (Canada) from January 2014 to March 2020. We identified psychosis-related outpatient visits, emergency department visits, hospitalizations, and inpatient length of stay, as well as incident cases of psychotic disorders, among people aged 14 to 60 years. RESULTS: We did not find evidence of increases in health service use or incident cases of psychotic disorders over the short-term (17 month) period following cannabis legalization. However, we found clear increasing trends in health service use and incident cases of substance-induced psychotic disorders over the entire observation window (2014-2020). CONCLUSION: Our findings suggest that the initial period of tight market restriction following legalization of non-medical cannabis was not associated with an increase in health service use or frequency of psychotic disorders. A longer post-legalization observation period, which includes expansion of the commercial cannabis market, is needed to fully understand the population-level impacts of non-medical cannabis legalization; thus, it would be premature to conclude that the legalization of non-medical cannabis did not lead to increases in health service use and incident cases of psychotic disorder.

Opioid-related overdose deaths among people experiencing homelessness, 2017 to 2021: A population-based analysis using coroner and health administrative data from Ontario, Canada.

AIMS: To measure the change in proportion of opioid-related overdose deaths attributed to people experiencing homelessness and to compare the opioid-related fatalities between individuals experiencing homelessness and not experiencing homelessness at time of death. DESIGN, SETTING AND PARTICIPANTS: Population-based, time-trend analysis using coroner and health administrative databases from Ontario, Canada from 1 July 2017 and 30 June 2021. MEASUREMENTS: Quarterly proportion of opioid-related overdose deaths attributed to people experiencing homelessness. We also obtained socio-demographic and health characteristics of decedents, health-care encounters preceding death, substances directly contributing to death and circumstances surrounding deaths. FINDINGS: A total of 6644 individuals (median age = 40 years, interquartile range = 31-51; 74.1% male) experienced an accidental opioid-related overdose death, among whom 884 (13.3%) were identified as experiencing homelessness at the time of death. The quarterly proportion of opioid-related overdose deaths attributed to people experiencing homelessness increased from 7.2% (26/359) in July-September 2017 to 16.8% (97/578) by April-June 2021 (trend test P < 0.01). Compared with housed decedents, those experiencing homelessness were younger (61.3 versus 53.1% aged 25-44), had higher prevalence of mental health or substance use disorders (77.1 versus 67.1%) and more often visited hospitals (32.1 versus 24.5%) and emergency departments (82.6 versus 68.5%) in the year prior to death. Fentanyl and its analogues more often directly contributed to death among people experiencing homelessness (94.0 versus 81.4%), as did stimulants (67.4 versus 51.6%); in contrast, methadone was less often present (7.8 versus 12.4%). Individuals experiencing homelessness were more often in the presence of a bystander during the acute toxicity event that led to death (55.8 versus 49.7%); and where another individual was present, more often had a resuscitation attempted (61.7 versus 55.1%) or naloxone administered (41.2 versus 28.9%). CONCLUSIONS: People experiencing homelessness account for an increasing proportion of fatal opioid-related overdoses in Ontario, Canada, reaching nearly one in six such deaths in 2021.

The association between household food insecurity and healthcare costs among Canadian children.

OBJECTIVE: To examine the relationship between household food insecurity and healthcare costs in children living in Ontario, Canada. METHODS: We conducted a cross-sectional, population-based study using four cycles of the Canadian Community Health Survey (2007-2008, 2009-2010, 2011-2012, 2013-2014) linked with administrative health databases (ICES). We included Ontario children aged 1-17 years with a measure of household food insecurity (Household Food Security Survey Module) over the previous 12 months. Our primary outcome was the direct public-payer healthcare costs per child over the same time period (in Canadian dollars, standardized to year 2020). We used gamma-log-transformed generalized estimating equations accounting for the clustering of children to examine this relationship, and adjusted models for important sociodemographic covariates. As a secondary outcome, we examined healthcare usage of specific services and associated costs (e.g. visits to hospitals, surgeries). RESULTS: We found that adjusted healthcare costs were higher in children from food-insecure than from food-secure households ($676.79 [95% CI: $535.26, $855.74] vs. $563.98 [$457.00, $695.99], p = 0.047). Compared with children living in food-secure households, those in insecure households more often accessed hospitals, emergency departments, day surgeries, and home care, and used prescription medications. Children from food-secure households had higher usage of non-physician healthcare (e.g. optometry) and family physician rostering services. CONCLUSION: Even after adjusting for measurable social determinants of health, household food insecurity was associated with higher public-payer health services costs and utilization among children and youth. Efforts to mitigate food insecurity could lessen child healthcare needs, as well as associated costs to our healthcare systems.

RéSUMé: OBJECTIF: Examiner la relation entre l'insécurité alimentaire des ménages et les coûts des soins de santé chez les enfants vivant en Ontario, au Canada. MéTHODE: Nous avons mené une étude populationnelle transversale en utilisant les quatre cycles de l'Enquête sur la santé dans les collectivités canadiennes (2007­2008, 2009­2010, 2011­2012, 2013­2014) liés à des bases de données administratives sur la santé (ICES). Nous avons inclus les enfants ontariens de 1 à 17 ans et un indicateur d'insécurité alimentaire des ménages (le Module d'enquête sur la sécurité alimentaire des ménages) au cours des 12 mois antérieurs. Les coûts directs des soins de santé publics par enfant au cours de cette période (en dollars canadiens de 2020) ont constitué notre résultat principal. Nous avons utilisé des équations d'estimation généralisées transformées par la fonction logarithme gamma tenant compte du regroupement des enfants pour analyser cette relation, et des modèles ajustés pour les covariables sociodémographiques importantes. Comme résultat secondaire, nous avons analysé l'utilisation de certains services de soins de santé (p. ex. les visites dans les hôpitaux, les chirurgies) et les coûts associés. RéSULTATS: Nous avons constaté que les coûts ajustés des soins de santé étaient plus élevés chez les enfants des ménages aux prises avec l'insécurité alimentaire que chez ceux des ménages à l'abri de l'insécurité alimentaire (676,79 $ [IC de 95%: 535,26 $, 855,74 $] contre 563,98 $ [457,00 $, 695,99 $], p = 0,047). Comparativement aux enfants des ménages à l'abri de l'insécurité alimentaire, ceux qui vivaient dans des ménages aux prises avec l'insécurité avaient plus souvent recours aux hôpitaux, aux services des urgences, aux chirurgies d'un jour et aux soins à domicile, et ils prenaient des médicaments sur ordonnance. Les enfants des ménages à l'abri de l'insécurité alimentaire avaient plus souvent recours aux soins de santé non médicaux (p. ex. l'optométrie) et aux services de leur médecin de famille attitré. CONCLUSION: Même après l'apport d'ajustements pour tenir compte des déterminants sociaux de la santé mesurables, l'insécurité alimentaire des ménages était associée à des coûts de soins de santé publics plus élevés et à une plus grande utilisation de ces soins chez les enfants et les jeunes. Des efforts pour atténuer l'insécurité alimentaire pourraient réduire les besoins de soins de santé des enfants, ainsi que les coûts associés pour nos systèmes de soins de santé.

The effect of non-medical cannabis retailer proximity on use of mental health services for psychotic disorders in Ontario, Canada.

BACKGROUND: Cannabis is associated with the onset and persistence of psychotic disorders. Evidence suggests that accessibility of substances is associated with an increased risk of use-related harms. We sought to examine the effect of residing in proximity to non-medical cannabis retailers on the prevalence of health service use for psychosis. METHODS: We conducted a cross-sectional study using linked health administrative data, and used geospatial analyses to determine whether people in Ontario, Canada (aged 14-60 years) resided within walking (1.6 km) or driving (5.0 km) distance of non-medical cannabis retailers (open as of February-2020). We identified outpatient visits, emergency department (ED) visits, and hospitalizations for psychotic disorders between 01-April-2019 and 17-March-2020. We used zero-inflated Poisson regression models and gamma generalized linear models to estimate the association between cannabis retailer proximity and indicators of health service use. RESULTS: Non-medical cannabis retailers were differentially located in areas with high levels of marginalization and pre-existing health service use for psychosis. People residing within walking or driving distance of a cannabis retailer had a higher rate of psychosis-related outpatient visits, ED visits, and hospitalizations, compared to people living outside these areas. This effect was stronger among those with no prior service use for psychosis. CONCLUSIONS: Proximity to a non-medical cannabis retailer was associated with higher health service use for psychosis, even after adjustment for prior health service use. These findings suggest that opening of non-medical cannabis retailers could worsen the burden of psychosis on mental health services in areas with high-risk populations.

Retrospective cohort analysis of outpatient antibiotic prescribing for community-acquired pneumonia in Canadian older adults.

BACKGROUND: This retrospective cohort study is the first in North America to examine population-level appropriate antibiotic use for community-acquired pneumonia (CAP) in older adults, by agent, dose and duration. With the highest rates of CAP reported in the elderly populations, appropriate antibiotic use is essential to improve clinical outcomes. Given the ongoing crisis of antimicrobial resistance, understanding inappropriate antibiotic prescribing is integral to direct community stewardship efforts. METHODS: All outpatient primary care visits for CAP (aged ≥65 years) were identified using physician billing codes between January 1 2014 to December 31 2018 in British Columbia (BC) and Ontario (ON). Categories of prescribing were derived from existing literature, and constructed for clinical relevance using Canadian and international guidelines available during the study period. Categories were mutually exclusive and included: guideline adherent (first-line agent, adherent dose/duration), clinically appropriate (non-first line agent, presence of comorbidities), effective but unnecessary (first-line agent, excess dose/duration), undertreatment (first-line agent, subtherapeutic dose/duration), and not recommended (non-first line agent, absence of comorbidities). Proportions of prescribing were examined by category. Temporal trends in prescribing were examined using Poisson regression. RESULTS: A total of 436,441 episodes of CAP were identified, with 46% prescribed an antibiotic in BC, and 52% in Ontario. Guideline adherent prescribing was minimal for both provinces (BC: 2%; ON: 1%) however the largest magnitude of increase was reported in this category by the final study year (BC-Rate Ratio [RR]: 3.4, 95% Confidence Interval [CI]: 2.7-4.3; ON-RR: 4.62, 95% CI: 3.4-6.5). Clinically appropriate prescribing accounted for the most antibiotics issued, across all study years (BC: 61%; ON: 74%) (BC-RR: 0.8, 95% CI: 0.8-0.8; ON-RR: 0.9, 95% CI: 0.8-0.9). Excess duration of therapy was the hallmark characteristic for effective but unnecessary prescribing (BC: 92%; ON: 99%). The most common duration prescribed was 7 days, followed by 10. Not recommended prescribing was minimal in both provinces (BC: 4%; ON: 7%) and remained stable by the final study year (BC-RR: 1.1, 95% CI: 0.9-1.2; ON-RR: 0.9, 95% CI: 0.9-1.1). CONCLUSION: Three quarters of antibiotic prescribing for CAP was appropriate in Ontario, but only two thirds in BC. Shortening durations-in line with evidence for 3 to 5-day treatment presents a focused target for stewardship efforts.

Quality of antibiotic prescribing for pediatric community-acquired Pneumonia in outpatient care.

BACKGROUND: Antibiotics remain the primary treatment for community acquired pneumonia (CAP), however rising rates of antimicrobial resistance may jeopardize their future efficacy. With higher rates of disease reported in the youngest populations, effective treatment courses for pediatric pneumonia are of paramount importance. This study is the first to examine the quality of pediatric antibiotic use by agent, dose and duration. METHODS: A retrospective cohort study included all outpatient/primary care physician visits for pediatric CAP (aged < 19 years) between January 1 2014 to December 31 2018. Relevant practice guidelines were identified, and treatment recommendations extracted. Amoxicillin was the primary first-line agent for pediatric CAP. Categories of prescribing included: guideline adherent, effective but unnecessary (excess dose and/or duration), under treatment (insufficient dose and/or duration), and not recommended. Proportions of attributable-antibiotic use were examined by prescribing category, and then stratified by age and sex. RESULT(S): A total of 42,452 episodes of pediatric CAP were identified. Of those, 31,347 (76%) resulted in an antibiotic prescription. Amoxicillin accounted for 51% of all prescriptions. Overall, 27% of prescribing was fully guideline adherent, 19% effective but unnecessary, 10% under treatment, and 44% not recommended by agent. Excessive duration was the hallmark of effective but unnecessary prescribing (97%) Macrolides accounted for the majority on non-first line agent use, with only 32% of not recommended prescribing preceded by a previous course of antibiotics. CONCLUSION(S): This study is the first in Canada to examine prescribing quality for pediatric CAP by agent, dose and duration. Utilizing first-line agents, and shorter-course treatments are targets for stewardship.

Household food insecurity and health service use for mental and substance use disorders among children and adolescents in Ontario, Canada.

BACKGROUND: Food insecurity is a serious public health problem and is linked to the mental health of children and adolescents; however, its relationship with mental health service use is unknown. We sought to estimate the association between household food insecurity and contact with health services for mental or substance use disorders among children and adolescents in Ontario, Canada. METHODS: We used health administrative data, linked to 5 waves of the Canadian Community Health Survey, to identify children and adolescents (aged 1-17 yr) who had a household response to the Household Food Security Survey Module. We identified contacts with outpatient and acute care services for mental or substance use disorders in the year before survey completion using administrative data. We estimated prevalence ratios for the association between household food insecurity and use of mental health services, adjusting for several confounding factors. RESULTS: The sample included 32 321 children and adolescents, of whom 5216 (16.1%) were living in food-insecure households. Of the total sample, 9.0% had an outpatient contact and 0.6% had an acute care contact for a mental or substance use disorder. Children and adolescents in food-insecure households had a 55% higher prevalence of outpatient contacts (95% confidence interval [CI] 41%-70%), and a 74% higher prevalence of acute care contacts (95% CI 24%-145%) for a mental or substance use disorder, although contacts for substance use disorders were uncommon. INTERPRETATION: Children and adolescents living in a food-insecure household have greater use of health services for mental or substance use disorders than those living in households without food insecurity. Focused efforts to support food-insecure families could improve child and adolescent mental health and reduce strain on the mental health system.

SARS-CoV-2 Testing and Complications Across 6 Waves of the COVID-19 Pandemic Among Individuals Recently Experiencing Homelessness in Ontario, Canada.

This cohort study compares the rates of SARS-CoV-2 testing and complications across 6 waves of the COVID-19 pandemic in Ontario, Canada, between individuals recently experiencing homelessness, low-income residents, and the general population.

Evaluation of a modernized supported housing intervention for individuals who experience severe and persistent mental illness in Ontario, Canada.

WHAT IS KNOWN ON THE SUBJECT: Supported housing approaches that include case management and increased opportunities for independence and personal autonomy for people who are living with severe and persistent mental illness (SPMI) have been found to help reduce hospitalizations and use of the emergency department. What is not fully clear is if these types of supported housing arrangements also influence the use of primary health care and other specialist services. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE: This study uncovered that individuals experiencing SPMI who lived in supported housing used more primary health care and specialist physician services, in the year following transition to this housing arrangement. WHAT ARE THE IMPLICATIONS FOR PRACTICE: The findings of this study suggest that supported housing arrangements for people experiencing SPMI may help in improving the personalization of health services for individual residents, including increasing access to both primary health care and specialist services. This is important for nursing practice, as the findings of the study show that supported housing arrangements for people experiencing SPMI may assist in better supporting their complex health care needs. ABSTRACT: INTRODUCTION: Supported housing for people who are living with severe and persistent mental illness (SPMI) has been found to help reduce hospitalizations and use of the emergency department. What is not fully clear is if these types of supported housing arrangements also influence the use of primary health care and other specialist services. AIM/QUESTION: The aim of this study was to compare the use of health services use of individuals with SPMI, before and after transition to the new supported housing program. METHOD: Using health care administrative databases, a pre-post cohort study was conducted examining the health system use of residents who transitioned from custodial to supported housing arrangements between 2017 and 2019. RESULTS: Individuals with SPMI used more primary health care and specialist physician services after transition to the supported housing model. DISCUSSION: The results suggest that a supported housing model may be associated with increased usage of outpatient person-centred health services in people experiencing SPMI. IMPLICATIONS FOR PRACTICE: The findings of this study suggest that supported housing arrangements for people experiencing SPMI may help in improving the personalization of health services for individual. This is important for nursing practice, as the findings of the study show that supported housing arrangements may assist in better supporting complex health care needs of individuals.

Epilepsy Surgery in Adult Stroke Survivors with New-Onset Drug-Resistant Epilepsy.

BACKGROUND: Despite its effectiveness, surgery for drug-resistant epilepsy is underutilized. However, whether epilepsy surgery is also underutilized among patients with stroke-related drug-resistant epilepsy is unclear. Therefore, our objectives were to estimate the rates of epilepsy surgery assessment and receipt among patients with stroke-related drug-resistant epilepsy and to identify factors associated with these outcomes. METHODS: We used linked health administrative databases to conduct a population-based retrospective cohort study of adult Ontario, Canada residents discharged from an Ontario acute care institution following the treatment of a stroke between January 1, 1997, and December 31, 2020, without prior evidence of seizures. We excluded patients who did not subsequently develop drug-resistant epilepsy and those with other epilepsy risk factors. We estimated the rates of epilepsy surgery assessment and receipt by March 31, 2021. We planned to use Fine-Gray subdistribution hazard models to identify covariates independently associated with our outcomes, controlling for the competing risk of death. RESULTS: We identified 265,081 patients who survived until discharge following inpatient stroke treatment, 1,902 (0.7%) of whom subsequently developed drug-resistant epilepsy (805 women; mean age: 67.0 ± 13.1 years). Fewer than six (≤0.3%) of these patients were assessed for or received epilepsy surgery before the end of follow-up (≤55.5 per 100,000 person-years). Given that few outcomes were identified, we could not proceed with the multivariable analyses. CONCLUSIONS: Patients with stroke-related drug-resistant epilepsy are infrequently considered for epilepsy surgery that could reduce morbidity and mortality.

Virtual family physician care during COVID-19: a mixed methods study using health administrative data and qualitative interviews.

BACKGROUND: The onset of the COVID-19 pandemic necessitated a rapid shift in primary health care from predominantly in-person to high volumes of virtual care. The pandemic afforded the opportunity to conduct a deep regional examination of virtual care by family physicians in London and Middlesex County, Ontario, Canada that would inform the foundation for virtual care in our region post-pandemic. OBJECTIVES: (1) to determine volumes of in-person and virtual family physicians visits and characteristics of the family physicians and patients using them during the early COVID-19 pandemic; (2) to determine how virtual visit volumes changed over the pandemic, compared to in-person; and (3) to explore family physicians' experience in virtual visit adoption and implementation. METHODS: We conducted a concurrent mixed-methods study of family physicians from March to October 2020. The quantitative component examined mean weekly number of total, in-person and virtual visits using health administrative data. Differences in outcomes according to physician and practice characteristics for pandemic periods were compared to pre-pandemic. The qualitative study employed Constructivist Grounded Theory, conducting semi-structured family physicians interviews; analyzing data iteratively using constant comparative analysis. We mapped themes from the qualitative analysis to quantitative findings. RESULTS: Initial volumes of patients decreased, driven by fewer in-person visits. Virtual visit volumes increased dramatically; family physicians described using telephone almost entirely. Rural family physicians reported video connectivity issues. By early second wave, total family physician visit volume returned to pre-pandemic volumes. In-person visits increased substantially; family physicians reported this happened because previously scarce personal protective equipment became available. Patients seen during the pandemic were older, sicker, and more materially deprived. CONCLUSION: These results can inform the future of virtual family physician care including the importance of continued virtual care compensation, the need for equitable family physician payment models, and the need to attend to equity for vulnerable patients. Given the move to virtual care was primarily a move to telephone care, the modality of care delivery that is acceptable to both family physicians and their patients must be considered.

Epilepsy Risk Following Bariatric Surgery for Weight Loss.

BACKGROUND AND OBJECTIVES: A previous study reported finding that epilepsy risk is elevated after bariatric surgery for weight loss; however, this association has not been adequately explored. Our objectives were to (1) estimate the risk of epilepsy after bariatric surgery for weight loss relative to a nonsurgical cohort of patients with an obesity diagnosis and (2) identify epilepsy risk factors among bariatric surgery recipients. METHODS: We conducted a population-based retrospective cohort study using linked health administrative databases in Ontario, Canada. Participants were accrued between July 1, 2010, and December 31, 2016, and followed until December 31, 2019. All Ontario residents aged 18 years and older who had bariatric surgery during the accrual period were eligible for inclusion in our exposed cohort. Patients hospitalized with a diagnosis of obesity and who did not have bariatric surgery during the accrual period were eligible for inclusion in our unexposed cohort. We excluded patients with a history of seizures, epilepsy, various seizure or epilepsy risk factors, psychiatric disorders, or drug or alcohol abuse/dependence. In our primary analysis, we used inverse probability of treatment weighting to control for confounding. A marginal Cox proportional hazards model was then used to estimate the risk of epilepsy associated with bariatric surgery. A Cox model was also used to identify epilepsy risk factors among exposed participants. RESULTS: The final sample included 16,958 exposed participants and 622,514 unexposed participants. After inverse probability of treatment weighting, the estimated rates of epilepsy were 50.1 and 34.1 per 100,000 person-years among those who did and did not have bariatric surgery, respectively. The hazard ratio for developing epilepsy after bariatric surgery was 1.45 (95% CI = 1.35, 1.56). Among participants who received bariatric surgery, stroke during follow-up increased epilepsy risk (HR = 14.03, 95% CI = 4.26, 46.25). DISCUSSION: In this study, we found that patients with a history of bariatric surgery were at increased risk of developing epilepsy. These findings suggest that epilepsy is a long-term risk associated with bariatric surgery for weight loss.

Impact of Ontario's Harmonized Heat Warning and Information System on emergency department visits for heat-related illness in Ontario, Canada: a population-based time series analysis.

INTERVENTION: Ontario's Harmonized Heat Warning and Information System (HWIS) brings harmonized, regional heat warnings and standard heat-health messaging to provincial public health units prior to periods of extreme heat. RESEARCH QUESTION: Was implementation of the harmonized HWIS in May 2016 associated with a reduction in emergency department (ED) visits for heat-related illness in urban locations across Ontario, Canada? METHODS: We conducted a population-based interrupted time series analysis from April 30 to September 30, 2012-2018, using administrative health and outdoor temperature data. We used autoregressive integrated moving average models to examine whether ED rates changed following implementation of the harmonized HWIS, adjusted for maximum daily temperature. We also examined whether effects differed in heat-vulnerable groups (≥65 years or <18 years, those with comorbidities, those with a recent history of homelessness), and by heat warning region. RESULTS: Over the study period, heat alerts became more frequent in urban areas (6 events triggered between 2013 and 2015 and 14 events between 2016 and 2018 in Toronto, for example). The mean rate of ED visits was 47.5 per 100,000 Ontarians (range 39.7-60.1) per 2-week study interval, with peaks from June to July each year. ED rates were particularly high in those with a recent history of homelessness (mean rate 337.0 per 100,000). Although rates appeared to decline following implementation of HWIS in some subpopulations, the change was not statistically significant at a population level (rate 0.04, 95% CI: -0.03 to 0.1, p=0.278). CONCLUSION: In urban areas across Ontario, ED encounters for heat-related illness may have declined in some subpopulations following HWIS, but the change was not statistically significant. Efforts to continually improve HWIS processes are important given our changing Canadian climate.

RéSUMé: INTERVENTION: Le système d'avertissement et d'information de chaleur harmonisé pour l'Ontario (SAIC) transmet des alertes régionales harmonisées sur la chaleur et des messages normalisés sur la chaleur et la santé aux unités de santé publique provinciales, avant les périodes de chaleur extrême. QUESTION DE RECHERCHE: La mise en œuvre du SAIC harmonisé en mai 2016 a-t-elle été associée à une réduction des visites aux urgences pour des maladies liées à la chaleur dans les zones urbaines de l'Ontario, au Canada? MéTHODES: Nous avons effectué une analyse de séries chronologiques interrompues basée sur la population du 30 avril au 30 septembre, 2012­2018, en utilisant des données administratives sur la santé et la température extérieure. Nous avons utilisé des modèles autorégressifs à moyenne mobile intégrée pour examiner si le taux de visites des urgences avait changé après la mise en œuvre du SAIC harmonisé, ajusté pour tenir compte de la température maximale quotidienne. Nous avons également examiné si les effets différaient pour les groupes vulnérables à la chaleur (≥65 ans ou <18 ans, les personnes ayant des comorbidités et les personnes avec un passé récent de sans-abri), et selon la région d'alerte de chaleur. RéSULTATS: Au cours de la période d'étude, les alertes de chaleur sont devenues plus fréquentes dans les zones urbaines (6 événements déclenchés entre 2013 et 2015 et 14 événements déclenchés entre 2016 et 2018 à Toronto, par exemple). Le taux moyen de visites aux urgences était de 47,5 pour 100 000 Ontariens (de 39,7 à 60,1) par intervalle de deux semaines, avec des pointes chaque année en juin et juillet. Le taux de visites aux urgences était particulièrement élevé chez les personnes avec un passé récent de sans-abri (taux moyen de 337,0 pour 100 000). Malgré une baisse du taux après la mise en œuvre du SAIC dans certaines sous-populations, le changement n'était pas statistiquement significatif au niveau de la population (taux 0,04, IC 95 % : -0,03 à 0,1, p=0,278). CONCLUSION: Dans les zones urbaines de l'Ontario, le nombre de consultations aux urgences pour des maladies liées à la chaleur a diminué dans certaines sous-populations après la mise en place du SAIC, mais le changement n'était pas statistiquement significatif. Les efforts visant à améliorer continuellement les processus du SAIC sont importants compte tenu de l'évolution du climat canadien.

Trends and Factors Associated with Suicide Deaths in Older Adults in Ontario, Canada.

Background: Suicide in older adults is a significant overlooked problem worldwide. This is especially true in Canada where a national suicide prevention strategy has not been established. Methods: Using linked health-care administrative databases, this population-level study (2011 to 2015) described the incidence of older adult suicide (aged 65+), and identified clinical and socio-demographic factors associated with suicide deaths. Results: The findings suggest that suicide remains a persistent cause of death in older adults, with an average annual suicide rate of about 100 per million people over the five-year study period. Factors positively associated with suicide vs. non-suicide death included being male, living in rural areas, having a mental illness, having a new dementia diagnosis, and having increased emergency department visits in the year prior to death; whereas, increased age, living in long-term care, having one or more chronic health condition, and increased interactions with primary health care were negatively associated with a suicide death. Conclusion: Factors associated with suicide death among older adults highlighted in this study may provide better insights for the development and/or improvement of suicide prevention programs and policies.

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

BACKGROUND: Hospitalizations fell precipitously among the general population during the COVID-19 pandemic. It remains unclear whether individuals experiencing homelessness experienced similar reductions. OBJECTIVE: To examine how overall and cause-specific hospitalizations changed among individuals with a recent history of homelessness (IRHH) and their housed counterparts during the first wave of the COVID-19 pandemic, using corresponding weeks in 2019 as a historical control. DESIGN: Population-based cohort study conducted in Ontario, Canada, between September 30, 2018, and September 26, 2020. PARTICIPANTS: In total, 38,617 IRHH, 15,022,368 housed individuals, and 186,858 low-income housed individuals matched on age, sex, rurality, and comorbidity burden. MAIN MEASURES: Primary outcomes included medical-surgical, non-elective (overall and cause-specific), elective surgical, and psychiatric hospital admissions. KEY RESULTS: Average rates of medical-surgical (rate ratio: 3.8, 95% CI: 3.7-3.8), non-elective (10.3, 95% CI: 10.1-10.4), and psychiatric admissions (128.1, 95% CI: 126.1-130.1) between January and September 2020 were substantially higher among IRHH compared to housed individuals. During the peak period (March 17 to June 16, 2020), rates of medical-surgical (0.47, 95% CI: 0.47-0.47), non-elective (0.80, 95% CI: 0.79-0.80), and psychiatric admissions (0.86, 95% CI: 0.84-0.88) were significantly lower among housed individuals relative to equivalent weeks in 2019. No significant changes were observed among IRHH. During the re-opening period (June 17-September 26, 2020), rates of non-elective hospitalizations for liver disease (1.41, 95% CI: 1.23-1.69), kidney disease (1.29, 95% CI: 1.14-1.47), and trauma (1.19, 95% CI: 1.07-1.32) increased substantially among IRHH but not housed individuals. Distinct hospitalization patterns were observed among IRHH even in comparison with more medically and socially vulnerable matched housed individuals. CONCLUSIONS: Persistence in overall hospital admissions and increases in non-elective hospitalizations for liver disease, kidney disease, and trauma indicate that the COVID-19 pandemic presented unique challenges for recently homeless individuals. Health systems must better address the needs of this population during public health crises.

COVID-19 vaccine coverage and factors associated with vaccine uptake among 23 247 adults with a recent history of homelessness in Ontario, Canada: a population-based cohort study.

BACKGROUND: People experiencing homelessness face a high risk of SARS-CoV-2 infection and transmission, as well as health complications and death due to COVID-19. Despite being prioritised for receiving the COVID-19 vaccine in many regions, little data are available on vaccine uptake in this vulnerable population. Using population-based health-care administrative data from Ontario, Canada-a region with a universal, publicly funded health system-we aimed to describe COVID-19 vaccine coverage (ie, the estimated percentage of people who have received a vaccine) and determinants of vaccine receipt among individuals with a recent history of homelessness. METHODS: We conducted a retrospective, population-based cohort study of adults (aged ≥18 years) with a recent experience of homelessness, inadequate housing, or shelter use as recorded in routinely collected health-care databases between June 14, 2020, and June 14, 2021 (a period within 6 months of Dec 14, 2020, when COVID-19 vaccine administration was initiated in Ontario). Participants were followed up from Dec 14, 2020, to Sept 30, 2021, for the receipt of one or two doses of a COVID-19 vaccine using the province's real-time centralised vaccine information system. We described COVID-19 vaccine coverage overall and within predefined subgroups. Using modified Poisson regression, we further identified sociodemographic factors, health-care usage, and clinical factors associated with receipt of at least one dose of a COVID-19 vaccine. FINDINGS: 23 247 individuals with a recent history of homelessness were included in this study. Participants were predominantly male (14 752 [63·5%] of 23 247); nearly half were younger than 40 years (11 521 [49·6%]) and lived in large metropolitan regions (12 123 [52·2%]); and the majority (18 226 [78·4%]) visited a general practitioner for an in-person consultation during the observation period. By Sept 30, 2021, 14 271 (61·4%; 95% CI 60·8-62·0) individuals with a recent history of homelessness had received at least one dose of a COVID-19 vaccine and 11 082 (47·7%; 47·0-48·3) had received two doses; in comparison, over the same period, 86·6% of adults in the total Ontario population had received a first dose and 81·6% had received a second dose. In multivariable analysis, factors positively associated with COVID-19 uptake were one or more outpatient visits to a general practitioner (adjusted risk ratio [aRR] 1·37 [95% CI 1·31-1·42]), older age (50-59 years vs 18-29 years: 1·18 [1·14-1·22], ≥60 years vs 18-29 years: 1·27 [1·22-1·31]), receipt of an influenza vaccine in either of the two previous influenza seasons (1·25 [1·23-1·28]), being identified as homeless via a visit to a community health centre versus exclusively a hospital-based encounter (1·13 [1·10-1·15]), receipt of one or more SARS-CoV-2 tests between March 1, 2020, and Sept 30, 2021 (1·23 [1·20-1·26]), and the presence of chronic health conditions (one condition: 1·05 [1·03-1·08]; two or more conditions: 1·11 [1·08-1·14]). By contrast, living in a smaller metropolitan region (aRR 0·92 [95% CI 0·90-0·94]) or rural location (0·93 [0·90-0·97]) versus large metropolitan regions were associated with lower uptake. INTERPRETATION: In Ontario, COVID-19 vaccine coverage among adults with a recent history of homelessness has lagged and, as of Sept 30, 2021, was 25 percentage points lower than that of the general adult population in Ontario for a first dose and 34 percentage points lower for a second dose. With high usage of outpatient health services among individuals with a recent history of homelessness, better utilisation of outpatient primary care structures might offer an opportunity to increase vaccine coverage in this population. Our findings underscore the importance of leveraging existing health and service organisations that are accessed and trusted by people who experience homelessness for targeted vaccine delivery. FUNDING: The Public Health Agency of Canada. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Drug Overdoses During the COVID-19 Pandemic Among Recently Homeless Individuals.

AIMS: To examine how weekly rates of emergency department (ED) visits for drug overdoses changed among individuals with a recent history of homelessness (IRHH) and their housed counterparts during the pre-pandemic, peak, and re-opening periods of the first wave of the COVID-19 pandemic, using corresponding weeks in 2019 as a historical control. DESIGN: Population-based retrospective cohort study conducted between September 30, 2018 and September 26, 2020. SETTING: Ontario, Canada. PARTICIPANTS: A total of 38 617 IRHH, 15 022 369 housed individuals, and 186 858 low-income housed individuals matched on age, sex, rurality, and comorbidity burden. MEASUREMENTS: ED visits for drug overdoses of accidental and undetermined intent. FINDINGS: Average rates of ED visits for drug overdoses between January and September 2020 were higher among IRHH compared with housed individuals (rate ratio [RR], 148.0; 95% CI, 142.7-153.5) and matched housed individuals (RR, 22.3; 95% CI, 20.7-24.0). ED visits for drug overdoses decreased across all groups by ~20% during the peak period (March 17 to June 16, 2020) compared with corresponding weeks in 2019. During the re-opening period (June 17 to September 26, 2020), rates of ED visits for drug overdoses were significantly higher among IRHH (RR, 1.56; 95% CI, 1.44-1.69), matched housed individuals (RR, 1.25; 95% CI, 1.08-1.46), and housed individuals relative to equivalent weeks in 2019 (RR, 1.07; 95% CI, 1.02-1.11). The relative increase in drug overdose ED visits among IRHH was larger compared with both matched housed individuals (P = 0.01 for interaction between group and year) and housed individuals (P < 0.001) during this period. CONCLUSIONS: Recently homeless individuals in Ontario, Canada experienced disproportionate increases in ED visits for drug overdoses during the re-opening period of the COVID-19 pandemic compared with housed people.