COVID-19 hospitalization, mortality and pre-mature mortality by a history of immigration in Ontario, Canada: a population-based cohort study.

Background: Immigrants in high-income countries experienced inequities in COVID-19 severe outcomes. We examined hospitalization and death throughout the pandemic, and change during the vaccine era, in Ontario, Canada. Methods: We conducted a population-based study using linked immigration and health data, following two cohorts for 20 months from January 1, 2020 (pre-vaccine) and September 1, 2021 (vaccine era). We used multivariable Poisson generalized estimating equation regression to estimate adjusted rate ratios (aRR) with 95% confidence intervals (CI), accounting for age, sex and co-morbidities. We calculated age-standardized years of life lost (ASYRs) rates by immigrant category. Findings: Of 11,692,387 community-dwelling adults in the pre-vaccine era cohort and 11,878,304 community-dwelling adults in the vaccine era cohort, 21.6% and 21.4% of adults in each era respectively were immigrants. Females accounted for 57.9% and 57.8% of sponsored family, and 68.4% and 67.6% of economic caregivers, in each era respectively. Compared to other Ontarians in the pre-vaccine era cohort, hospitalization rates were highest for refugees (aRR [95% CI] 3.41 [3.39-3.44]) and caregivers (3.13 [3.07-3.18]), followed by sponsored family and other economic immigrants. Compared to other Ontarians, aRRs were highest for immigrants from Central America (5.00 [4.92-5.09]), parts of South Asia (3.95 [3.89-4.01]) and Jamaica (3.56 [3.51-3.61]) with East Asians having lower aRRs. Mortality aRRs were similar to hospitalization aRRs. In the vaccine era, all aRRs were attenuated and most were similar to or lower than other Ontarians, with refugees and a few regions maintaining higher rates. In the pre-vaccine era ASYRs were higher for all immigrant groups. ASYRs dropped in the vaccine era with only refugees continuing to have higher rates. Interpretation: Immigrants, particularly refugees, experienced greater premature mortality. aRRs for most immigrant groups dropped substantially after high vaccine coverage was achieved. Vaccine outreach and improvements in the social determinants of health are needed. Funding: Canadian Institutes of Health Research, Canada Research Chairs Program.

Acute health care use among children during the first 2.5 years of the COVID-19 pandemic in Ontario, Canada: a population-based repeated cross-sectional study.

BACKGROUND: The effects of the decline in health care use at the start of the COVID-19 pandemic on the health of children are unclear. We sought to estimate changes in rates of severe and potentially preventable health outcomes among children during the pandemic. METHODS: We conducted a repeated cross-sectional study of children aged 0-17 years using linked population health administrative and disease registry data from January 2017 through August 2022 in Ontario, Canada. We compared observed rates of emergency department visits and hospital admissions during the pandemic to predicted rates based on the 3 years preceding the pandemic. We evaluated outcomes among children and neonates overall, among children with chronic health conditions and among children with specific diseases sensitive to delays in care. RESULTS: All acute care use for children decreased immediately at the onset of the pandemic, reaching its lowest rate in April 2020 for emergency department visits (adjusted relative rate [RR] 0.28, 95% confidence interval [CI] 0.28-0.29) and hospital admissions (adjusted RR 0.43, 95% CI 0.42-0.44). These decreases were sustained until September 2021 and May 2022, respectively. During the pandemic overall, rates of all-cause mortality, admissions for ambulatory care-sensitive conditions, newborn readmissions or emergency department visits or hospital admissions among children with chronic health conditions did not exceed predicted rates. However, after declining significantly between March and May 2020, new presentations of diabetes mellitus increased significantly during most of 2021 (peak adjusted RR 1.49, 95% CI 1.28-1.74 in July 2021) and much of 2022. Among these children, presentations for diabetic ketoacidosis were significantly higher than expected during the pandemic overall (adjusted RR 1.14, 95% CI 1.00-1.30). We observed similar time trends for new presentations of cancer, but we observed no excess presentations of severe cancer overall (adjusted RR 0.91, 95% CI 0.62-1.34). INTERPRETATION: In the first 30 months of the pandemic, disruptions to care were associated with important delays in new diagnoses of diabetes but not with other acute presentations of select preventable conditions or with mortality. Mitigation strategies in future pandemics or other health system disruptions should include education campaigns around important symptoms in children that require medical attention.

COVID-19 vaccine equity: a retrospective population-based cohort study examining primary series and first booster coverage among persons with a history of immigration and other residents of Ontario, Canada.

Introduction: Immigrants were disproportionately impacted by COVID-19 and experience unique vaccination barriers. In Canada (37 million people), 23% of the population is foreign-born. Immigrants constitute 60% of the country's racialized (non-white) population and over half of immigrants reside in Ontario, the country's most populous province. Ontario had several strategies aimed at improving vaccine equity including geographic targeting of vaccine supply and clinics, as well as numerous community-led efforts. Our objectives were to (1) compare primary series vaccine coverage after it was widely available, and first booster coverage 6 months after its availability, between immigrants and other Ontario residents and (2) identify subgroups experiencing low coverage. Materials and methods: Using linked immigration and health administrative data, we conducted a retrospective population-based cohort study including all community-dwelling adults in Ontario, Canada as of January 1, 2021. We compared primary series (two-dose) vaccine coverage by September 2021, and first booster (three-dose) coverage by March 2022 among immigrants and other Ontarians, and across sociodemographic and immigration characteristics. We used multivariable log-binomial regression to estimate adjusted risk ratios (aRR). Results: Of 11,844,221 adults, 22% were immigrants. By September 2021, 72.6% of immigrants received two doses (vs. 76.4%, other Ontarians) and by March 2022 46.1% received three doses (vs. 58.2%). Across characteristics, two-dose coverage was similar or slightly lower, while three-dose coverage was much lower, among immigrants compared to other Ontarians. Across neighborhood SARS-CoV-2 risk deciles, differences in two-dose coverage were smaller in higher risk deciles and larger in the lower risk deciles; with larger differences across all deciles for three-dose coverage. Compared to other Ontarians, immigrants from Central Africa had the lowest two-dose (aRR = 0.60 [95% CI 0.58-0.61]) and three-dose coverage (aRR = 0.36 [95% CI 0.34-0.37]) followed by Eastern Europeans and Caribbeans, while Southeast Asians were more likely to receive both doses. Compared to economic immigrants, resettled refugees and successful asylum-claimants had the lowest three-dose coverage (aRR = 0.68 [95% CI 0.68-0.68] and aRR = 0.78 [95% CI 0.77-0.78], respectively). Conclusion: Two dose coverage was more equitable than 3. Differences by immigrant region of birth were substantial. Community-engaged approaches should be re-invigorated to close gaps and promote the bivalent booster.

Population-Based Repeated Cross-Sectional Study of Hospitalizations for Comorbid Physical and Psychiatric Disorders in Young Adults in Ontario, Canada.

PURPOSE: To measure trends in the rates and costs of hospitalizations over a 15-year period among young adults with physical and/or psychiatric disorders. METHODS: This population-based, repeated cross-sectional study identified all 18- to 26- year-olds hospitalized in Ontario, Canada from April 1, 2003 and March 31, 2018 (fiscal years 2003-2017). Using discharge diagnoses, we assigned hospitalizations to one of four categories: 1) psychiatric disorder only; 2) primary psychiatric disorder with comorbid physical illness; 3) primary physical with comorbid psychiatric disorder; and 4) physical illness only. We compared health service utilization and changes in rates of hospitalizations over time using restricted cubic spline regression. Secondary outcome measures included change in hospital costs for each hospitalization category over the study period. RESULTS: Of 1,076,951 hospitalizations in young adults (73.7% female), 195,726 (18.2%) had a psychiatric disorder (either primary or comorbid). There were 129,676 hospitalizations (12.0%) with psychiatric disorders only, 36,287 (3.4%) with primary psychiatric and comorbid physical disorders, 29,763 (2.8%) with primary physical and comorbid psychiatric disorders, and 881,225 (81.8%) with physical disorders only. Rates of hospitalization for psychiatric disorders only increased 81% from 4.32 to 7.84/1,000 population, and those with physical health disorders with comorbid psychiatric disorders increased 172% from 0.47 to 1.28/1,000 population. Substance-related disorders were the most common comorbid psychiatric disorders among youth hospitalized for physical illness and increased 260% from 0.9 to 3.3/1,000 population. DISCUSSION: Hospitalizations among young adults with primary and comorbid psychiatric disorders have increased significantly over the past 15 years. Health system resources should be adequately directed to meet the shifting and complex needs of hospitalized young adults.

Primary health care utilization in the first year after arrival by refugee sponsorship model in Ontario, Canada: A population-based cohort study.

BACKGROUND: Canada's approach to refugee resettlement includes government sponsorship, a pioneering private sponsorship model and a third blended approach. Refugees are selected and supported differently in each approach including healthcare navigation. Little is known about how well private sponsors facilitate primary care navigation and whether this changed during the large-scale 2015 Syrian resettlement initiative characterized by civic and healthcare systems engagement. METHODS AND FINDINGS: Population-based cohort study of resettled refugees arriving in Ontario between April 1, 2008 and March 31, 2017, with one-year follow-up, using linked health and demographic administrative databases. We evaluated associations of resettlement model (GARs, Privately Sponsored Refugees [PSRs], and Blended-Visa Office Referred [BVORs]) by era of arrival (pre-Syrian and Syrian era) and by country cohort, on measures of primary care (PC) navigation using adjusted Cox proportional hazards and logistic regression. There were 34,591 (pre-Syrian) and 24,757 (Syrian era) resettled refugees, approximately half of whom were GARs. Compared with the reference group pre-Syrian era PSRs, Syrian PSRs had slightly earlier PC visits (mean = 116 days [SD = 90]) (adjusted hazard ratios [aHR] = 1.19, 95% CI 1.14-1.23). Syrian GARs (mean = 72 days [SD = 65]) and BVORs (mean = 73 days [SD = 76]) had their first PC visit sooner than pre-Syrian era PSRs (mean = 149 days [SD = 86]), with respective aHRs 2.27, 95% CI 2.19-2.35 and 1.89, 95% CI 1.79-1.99. Compared to pre-Syrian PSRs, Syrian GARs and BVORs had much greater odds of a CHC visit (adjusted odds ratios 14.69, 95% CI 12.98-16.63 and 14.08, 95% 12.05-16.44 respectively) and Syrian PSRs had twice the odds of a CHC visit. CONCLUSIONS: Less timely primary care and lower odds of a CHC visit among PSRs in the first year may be attributed to selection factors and gaps in sponsors' knowledge of healthcare navigation. Improved primary care navigation outcomes in the Syrian era suggests successful health systems engagement.

Receipt of adequate prenatal care for privately sponsored versus government-assisted refugees in Ontario, Canada: a population-based cohort study.

BACKGROUND: Canada has 2 main streams of resettlement: government-assisted refugees and privately sponsored refugees, whereby citizens can privately sponsor refugees and provide resettlement services, including health care navigation. Our objective was to compare receipt of adequate prenatal care among privately sponsored and government-assisted refugees. METHODS: This population-based study used linked health administrative and demographic databases. We included all resettled refugees classified as female who landed in Ontario, Canada, between April 2002 and May 2017, and who had a live birth or stillbirth conceived at least 365 days after their landing date. Our primary outcome - adequacy of prenatal care - was a composite that comprised receipt of a first-trimester prenatal visit, the number of prenatal care visits recommended by the Society of Obstetricians and Gynaecologists of Canada and a prenatal fetal anatomy ultrasound. We accounted for potential confounding with inverse probability of treatment weighting, using a propensity score. RESULTS: We included 2775 government-assisted and 2374 privately sponsored refugees. Compared with privately sponsored refugees (62.3% v. 69.3%), government-assisted refugees received adequate prenatal care less often, with a weighted relative risk of 0.93 (95% confidence interval 0.88-0.95). INTERPRETATION: Among refugees resettled to Canada, a government-assisted resettlement model was associated with receiving less adequate prenatal care than a private sponsorship model. Government-assisted refugees may benefit from additional support in navigating health care beyond the first year after arrival.

Effectiveness of Structured Care Coordination for Children With Medical Complexity: The Complex Care for Kids Ontario (CCKO) Randomized Clinical Trial.

Importance: Children with medical complexity (CMC) have chronic conditions and high health needs and may experience fragmented care. Objective: To compare the effectiveness of a structured complex care program, Complex Care for Kids Ontario (CCKO), with usual care. Design, Setting, and Participants: This randomized clinical trial used a waitlist variation for randomizing patients from 12 complex care clinics in Ontario, Canada, over 2 years. The study was conducted from December 2016 to June 2021. Participants were identified based on complex care clinic referral and randomly allocated into an intervention group, seen at the next available clinic appointment, or a control group that was placed on a waitlist to receive the intervention after 12 months. Intervention: Assignment of a nurse practitioner-pediatrician dyad partnering with families in a structured complex care clinic to provide intensive care coordination and comprehensive plans of care. Main Outcomes and Measures: Co-primary outcomes, assessed at baseline and at 6, 12, and 24 months postrandomization, were service delivery indicators from the Family Experiences With Coordination of Care that scored (1) coordination of care among health care professionals, (2) coordination of care between health care professionals and families, and (3) utility of care planning tools. Secondary outcomes included child and parent health outcomes and child health care system utilization and cost. Results: Of 144 participants randomized, 141 had complete health administrative data, and 139 had complete baseline surveys. The median (IQR) age of the participants was 29 months (9-102); 83 (60%) were male. At 12 months, scores for utility of care planning tools improved in the intervention group compared with the waitlist group (adjusted odds ratio, 9.3; 95% CI, 3.9-21.9; P < .001), with no difference between groups for the other 2 co-primary outcomes. There were no group differences for secondary outcomes of child outcomes, parent outcomes, and health care system utilization and cost. At 24 months, when both groups were receiving the intervention, no primary outcome differences were observed. Total health care costs in the second year were lower for the intervention group (median, CAD$17 891; IQR, 6098-61 346; vs CAD$37 524; IQR, 9338-119 547 [US $13 415; IQR, 4572-45 998; vs US $28 136; IQR, 7002-89 637]; P = .01). Conclusions and Relevance: The CCKO program improved the perceived utility of care planning tools but not other outcomes at 1 year. Extended evaluation periods may be helpful in assessing pediatric complex care interventions. Trial Registration: ClinicalTrials.gov Identifier: NCT02928757.

Effect of a health system payment and quality improvement programme for tonsillectomy in Ontario, Canada: an interrupted time series analysis.

BACKGROUND: Tonsillectomy is among the most common and cumulatively expensive surgical procedures in children, with known variations in quality of care. However, evidence on health system interventions to improve quality of care is limited. The Quality-Based Procedures (QBP) programme in Ontario, Canada, introduced fixed episode hospital payment per tonsillectomy and disseminated a perioperative care pathway. We determined the association of this payment and quality improvement programme with tonsillectomy quality of care. METHODS: Interrupted time series analysis of children undergoing elective tonsillectomy at community and children's hospitals in Ontario in the QBP period (1 April 2014 to 31 December 2018) and the pre-QBP period (1 January 2009 to 31 January 2014) using health administrative data. We compared the age-standardised and sex-standardised rates for all-cause tonsillectomy-related revisits within 30 days, opioid prescription fills within 30 days and index tonsillectomy inpatient admission. RESULTS: 111 411 children underwent tonsillectomy: 51 967 in the QBP period and 59 444 in the pre-QBP period (annual median number of hospitals, 86 (range 77-93)). Following QBP programme implementation, revisit rates decreased for all-cause tonsillectomy-related revisits (0.48 to -0.18 revisits per 1000 tonsillectomies per month; difference -0.66 revisits per 1000 tonsillectomies per month (95% CI -0.97 to -0.34); p<0.0001). Codeine prescription fill rate continued to decrease but at a slower rate (-4.81 to -0.11 prescriptions per 1000 tonsillectomies per month; difference 4.69 (95% CI 3.60 to 5.79) prescriptions per 1000 tonsillectomies per month; p<0.0001). The index tonsillectomy inpatient admission rate decreased (1.12 to 0.23 admissions per 1000 tonsillectomies per month; difference -0.89 (95% CI -1.33 to -0.44) admissions per 1000 tonsillectomies per month; p<0.0001). CONCLUSIONS: The payment and quality improvement programme was associated with several improvements in quality of care. These findings may inform jurisdictions planning health system interventions to improve quality of care for tonsillectomy and other paediatric procedures.

Health Care Use and System Costs Among Pediatric Refugees in Canada.

BACKGROUND: Resettled refugees land in Canada through 3 sponsorship models with similar health insurance and financial supports but differences in how resettlement is facilitated. We examined whether health system utilization, costs, and aggregate 1-year morbidity differed by resettlement model. METHODS: Population-based matched cohort study in Ontario, 2008 to 2018, including pediatric (0-17 years) resettled refugees and matched Ontario-born peers and categorized refugees by resettlement model: (1) private sponsorship (PSRs), (2) Blended Visa Office-Referred program (BVORs), and (3) government-assisted refugee (GAR). Primary outcomes were health system utilization and costs in year 1 in Canada. Multivariable logistic regression was used to test the associations between sponsorship model and major illnesses. RESULTS: We included 23 287 resettled refugees (13 360 GARs, 1544 BVORs, 8383 PSRs) and 93 148 matched Ontario-born. Primary care visits were highest among GARs and lowest in PSRs (median visits [interquartile range], GARs 4[2-6]; BVORs 3[2-5]; PSRs 3[2-5]; P <.001). Emergency department visits and hospitalizations were more common among GARs and BVORs versus PSRs (emergency department: GARs 19.2%; BVORs 23.4%; PSRs 13.8%; hospitalizations: GARs 2.5%; BVORs 3.2%; PSRs 1.1%, P <.001). Mean 1-year health system costs were highest among GARs (mean [standard deviation] $1278 [$7475]) and lowest among PSRs ($555 [$2799]; Ontario-born $851 [9226]). Compared with PSRs, GARs (adjusted odds ratio 1.63, 95% confidence interval 1.47-1.81) and BVORs (adjusted odds ratio 1.52, 95% confidence interval 1.26-1.84) were more likely to have major illnesses. CONCLUSIONS: Health care use and morbidity of PSRs suggests they are healthier and less costly than GARs and BVOR model refugees. Despite a greater intensity of health care utilization than Ontario-born, overall excess demand on the health system for all resettled refugee children is low.

Variation in low-value radiograph use for children in the emergency department: a cross-sectional study of administrative databases.

BACKGROUND: Radiograph use contributes to low-value care for children in emergency departments (EDs), but little is known about systemic factors associated with their use. This study compares low-value radiograph use across ED settings by hospital type, pediatric volumes and physician specialty. METHODS: This is a cross-sectional study of routinely collected administrative data. We included children (age 0-18 yr) discharged from EDs in Ontario, Canada, between 2010 and 2019 with diagnoses of bronchiolitis, asthma, abdominal pain and constipation. Multiple clinical practice guidelines recommend against routine radiograph use in these conditions. Logistic regression evaluated odds of low-value radiograph by ED setting (pediatric academic [referent], adult academic, community with or without pediatric consultation services), pediatric volume and physician specialty (pediatric emergency medicine [PEM, referent], emergency medicine [EM], family medicine with EM training, pediatrics, family medicine), adjusting for demographic, clinical and provider characteristics. We used generalized estimating equations to account for clustering by ED. RESULTS: Of the total 9 862 787 eligible pediatric ED discharges in Ontario, 60 914 children had bronchiolitis, 141 921 asthma, 333 332 abdominal pain and 110 514 constipation; 26.0% received low-value radiographs. Compared with pediatric EDs and PEM physicians (referents), patients with bronchiolitis were most likely to have a chest radiograph in adult academic EDs (adjusted odds ratio [OR] 5.1 [95% confidence interval (CI) 4.6-5.6]) and by family physicians with EM training (adjusted OR 4.8 [95% CI 4.5-5.1]). Patients with asthma were more likely to have a chest radiograph in adult academic EDs (adjusted OR 3.0 [95% CI 2.8-3.2]) and by EM physicians (adjusted OR 2.8 [95% CI 2.6-3.0]). Patients with abdominal pain and constipation were more likely to have abdominal radiographs in community hospitals with pediatric consultation (adjusted OR 1.6 [95% CI 1.6-1.7] and 2.3 [95% CI 2.3-2.4], respectively) and by family physicians with EM training (adjusted OR 1.6 [95% CI 1.6-1.7] and 2.1 [95% CI 2.0-2.2], respectively). INTERPRETATION: Over the decade-long study period, low-value radiograph use was frequent for children with 4 common conditions seen in Ontario EDs. Quality improvement initiatives aimed at reducing unnecessary radiographs in children should focus on EM physicians practising in EDs that primarily treat adult patients.

Health System-Level Evaluation of Tele-Mental Health Services Among Children and Adolescents in Ontario, Canada.

OBJECTIVE: To describe the characteristics of children and adolescents receiving tele-mental health services in Ontario, Canada and examine access to a psychiatrist, in-person or via tele-mental health services, following a mental health and addictions (MHA)-related emergency department (ED) visit or hospitalization. METHOD: Using linked health and administrative data, we described two cohorts: (1) children and adolescents (1-18 years) who used a provincial tele-mental health programme from January 1, 2013 to March 31, 2017, comparing their MHA-related service use (outpatient, ED, hospitalization) in the 1 year prior to and the 1 year following initial consultation; (2) children and adolescents with high mental health service needs, defined as those with an incident MHA-related ED visit or hospitalization between January 1, 2013 and December 31, 2016, examining their 1-year follow-up with telemedicine and other health care utilization. RESULTS: In the first cohort, 7,216 children and adolescents (mean age 11.8 [±3.8] years) received tele-mental health services. The proportion of MHA-related ED visits [15.1% pre vs. 12.6% post (test statistic 23.57, P < 0.001)] or hospitalizations [10.2% pre vs. 8.7% post (test statistic 11.96, P < 0.001)] declined in the year following tele-mental health consultation, while local psychiatry visits increased [8.4% pre vs. 17.0% post (test statistic 298.69, P < 0.001)]. In the second cohort (n = 84,033), only 1.5% received tele-mental health services, 40.7% saw a psychiatrist in-person, and 32.5% received no MHA-related outpatient care in follow-up. CONCLUSIONS: Tele-mental health services were rarely used in Ontario, even among high-needs children and adolescents, despite their association with increased access to care and less need for acute mental health care.

Pediatric primary care in Ontario and Manitoba after the onset of the COVID-19 pandemic: a population-based study.

BACKGROUND: There were large disruptions to health care services after the onset of the COVID-19 pandemic. We sought to describe the extent to which pandemic-related changes in service delivery and access affected use of primary care for children overall and by equity strata in the 9 months after pandemic onset in Manitoba and Ontario. METHODS: We performed a population-based study of children aged 17 years or less with provincial health insurance in Ontario or Manitoba before and during the COVID-19 pandemic (Jan. 1, 2017-Nov. 28, 2020). We calculated the weekly rates of in-person and virtual primary care well-child and sick visits, overall and by age group, neighbourhood material deprivation level, rurality and immigrant status, and assessed changes in visit rates after COVID-19 restrictions were imposed compared to expected baseline rates calculated for the 3 years before pandemic onset. RESULTS: Among almost 3 million children in Ontario and more than 300 000 children in Manitoba, primary care visit rates declined to 0.80 (95% confidence interval [CI] 0.77-0.82) of expected in Ontario and 0.82 (95% CI 0.79-0.84) of expected in Manitoba in the 9 months after the onset of the pandemic. Virtual visits accounted for 53% and 29% of visits in Ontario and Manitoba, respectively. The largest monthly decreases in visits occurred in April 2020. Although visit rates increased slowly after April 2020, they had not returned to prerestriction levels by November 2020 in either province. Children aged more than 1 year to 12 years experienced the greatest decrease in visits, especially for well-child care. Compared to prepandemic levels, visit rates were lowest among rural Manitobans, urban Ontarians and Ontarians in low-income neighbourhoods. INTERPRETATION: During the study period, the pandemic contributed to rapid, immediate and inequitable decreases in primary care use, with some recovery and a substantial shift to virtual care. Postpandemic planning must consider the need for catch-up visits, and the long-term impacts warrant further study.

Maternal cardiovascular disease after twin pregnancies complicated by hypertensive disorders of pregnancy: a population-based cohort study.

BACKGROUND: People whose singleton pregnancy is affected by hypertensive disorders of pregnancy (HDP) are at risk of future cardiovascular disease. It is unclear, however, whether this association can be extrapolated to twin pregnancies. We aimed to compare the association between HDP and future cardiovascular disease after twin and singleton pregnancies. METHODS: We conducted a population-based retrospective cohort study that included nulliparous people in Ontario, Canada, 1992-2017. We compared the future risk of cardiovascular disease among pregnant people from the following 4 groups: those who delivered a singleton without HDP (referent) and with HDP, and those who delivered twins either with or without HDP. RESULTS: The populations of the 4 groups were as follows: 1 431 651 pregnant people in the singleton birth without HDP group; 98 631 singleton birth with HDP; 21 046 twin birth without HDP; and 4283 twin birth with HDP. The median duration of follow-up was 13 (interquartile range 7-20) years. The incidence rate of cardiovascular disease was lowest among those with a singleton or twin birth without HDP (0.72 and 0.74 per 1000 person-years, respectively). Compared with people with a singleton birth without HDP, the risk of cardiovascular disease was highest among those with a singleton birth and HDP (1.47 per 1000 person-years; adjusted hazard ratio [HR] 1.81 [95% confidence interval (CI) 1.72-1.90]), followed by people with a twin pregnancy and HDP (1.07 per 1000 person-years; adjusted HR 1.36 [95% CI 1.04-1.77]). The risk of the primary outcome after a twin pregnancy with HDP was lower than that after a singleton pregnancy with HDP (adjusted HR 0.74 [95% CI 0.57-0.97]), when compared directly. INTERPRETATION: In a twin pregnancy, HDP are weaker risk factors for postpartum cardiovascular disease than in a singleton pregnancy.

Incidence of Access to Ambulatory Mental Health Care Prior to a Psychiatric Emergency Department Visit Among Adults in Ontario, 2010-2018.

Importance: Psychiatric emergency department (ED) visits may be avoidable if individuals have access to adequate outpatient care, but the extent to which individuals use the ED itself as a key point of access is largely unknown. Objective: To describe the extent to which the ED is a first point of contact for mental health care among adults, and identify key factors associated with this outcome. Design, Setting, and Participants: This cohort study was conducted from 2010 to 2018 in Ontario, Canada. Using health care administrative data, all individuals aged 16 years and older with an incident psychiatric ED visit were included. Statistical analysis was performed from September 2019 to February 2021. Main Outcomes and Measures: The primary outcome was no outpatient mental health or addictions contact in the 2 years preceding the incident ED visit. The study also measured predisposing (age, sex, immigrant status, comorbidity), enabling (neighborhood income, rurality, continuity of primary care), and need factors (diagnosis from incident ED visit) associated with the so-called first-contact ED visits, generating adjusted odds ratios (aORs) and 95% CIs. Results: The cohort included 659 084 patients who visited the ED. Among these patients, 340 354 were female individuals (51.6%), and the mean (SD) age was 39.1 (18.5) years. The incident ED visit was a first contact for 298 924 individuals (45.4%). Patients who had increased odds of first-contact ED visits included older individuals (aged 65-84 years vs 16-24 years; aOR, 1.13; 95% CI, 1.12-1.14), male individuals (aOR, 1.14; 95% CI, 1.13-1.15), immigrants (eg, economic class immigrant vs nonimmigrant status: aOR, 1.20; 95% CI, 1.18-1.21), rural residents (aOR, 1.21; 95% CI, 1.20-1.21), and in those with minimal primary care (aOR, 1.68; 95% CI, 1.67-1.69). All diagnoses had a higher likelihood of first-contact ED visits than mood disorders, particularly substance and alcohol use disorders (aOR, 1.66; 95% CI, 1.65-1.68). Conclusions and Relevance: This study's results suggest that nearly half of incident psychiatric ED visits were first-contact visits, which may be avoidable. Targeted efforts to improve outpatient access should focus on populations with risk factors for first-contact ED presentations, including men, older adults, rural residents, those with poor primary care connectivity, and those with substance-related diagnoses.

Acute Care Visits for Assault and Maltreatment Before vs During the COVID-19 Pandemic in Ontario, Canada.

This cross-sectional study compares rates of emergency department visits and hospitalizations for assault and maltreatment by age category and sex in Ontario, Canada, before vs during the COVID-10 pandemic.

Health Care Use and Costs of Children, Adolescents, and Young Adults With Somatic Symptom and Related Disorders.

Importance: Somatic symptom and related disorders are highly prevalent mental health disorders among young people. Presentation can be varied, and patients often face long delays and see multiple practitioners to receive a diagnosis. Objective: To evaluate the health care use and costs in a population-based sample of children and young people with somatic symptom and related disorders in Ontario, Canada. Design, Setting, and Participants: This population-based cohort study used linked health and administrative databases in Ontario, Canada, where health services are funded through a universal single-payer health insurance plan. Participants included children aged 4 to 12 years, adolescents aged 13 to 17 years, and young adults aged 18 to 24 years residing in Ontario, Canada, during the period of April 1, 2008, to March 31, 2015. Included participants had a first health record diagnosis of somatic symptom and related disorders and were grouped based on the setting of their index somatic symptom and related disorders contact: outpatient, emergency department, or inpatient. Data were analyzed from August 1, 2017, to February 1, 2018. Exposures: One year before and 1 year after diagnosis of somatic symptom and related disorders. Main Outcomes and Measures: Outcome measures included overall and mental health-specific ambulatory and acute care visits and overall health system costs and sector-specific costs. Results: A total of 33 272 patients (median [interquartile range {IQR}] age, 20 [16-22] years; 17 387 female [52.3%]) were included in the analysis. Among these patients, 3875 (11.6%) were aged 4 to 12 years, 7273 (21.9%) were aged 13 to 17 years, and 22 124 (66.5%) were aged 18 to 24 years. A total of 17 893 (53.8%) had their index visit as outpatients, whereas 13 310 (40.0%) and 2069 (6.2%) were diagnosed in the emergency department and inpatient settings, respectively. Ambulatory physician visits were frequent and persisted 1 year after diagnosis within each setting (before vs after 1 year, median [IQR] visits, inpatient setting: 7 [3-13] vs 7 [3-13]; emergency department setting: 4 [2-8] vs 4 [2-9]; outpatient setting: 3 [1-7] vs 4 [2-7]; P < .001). After diagnosis, many did not receive physician-delivered mental health care (35.3% [730 of 2069] in an inpatient setting, 59.1% [7866 of 13 310] in an emergency department setting, 58.5% [10 467 of 17 893] in an outpatient setting; P < .001). Acute care use was frequent and remained so after diagnosis across settings. Of those hospitalized as inpatients at diagnosis, 37.7% (779 of 2069) were readmitted within 1 year. Mean (SD) 2-year patient costs were CAD$9845 ($39 725) (median [IQR], $2401 [$960-$7019]). Hospitalized patients had a 2-year mean (SD) cost of $51 424 ($100 416) (median [IQR], $21 997 [$12 510-$45 841]) per-patient expenditure. Conclusion and Relevance: This study found that children and young people with somatic symptom and related disorders frequently used the health system with substantial health system costs before and after diagnosis. Many of these patients did not receive physician-delivered mental health care. These findings suggest that this population may be under-recognized, and initiatives for early recognition and engagement with mental health support may be warranted.

Implementation of a Physician Incentive Program for 18-Month Developmental Screening in Ontario, Canada.

OBJECTIVES: To evaluate factors associated with uptake of a financial incentive for developmental screening at an enhanced 18-month well-child visit (EWCV) in Ontario, Canada. STUDY DESIGN: Population-based cohort study using linked administrative data of children (17-24 months of age) eligible for EWCV between 2009 and 2017. Logistic regression modeled associations of EWCV receipt by provider and patient characteristics. RESULTS: Of 910 976 eligible children, 54.2% received EWCV (annually, 39.2%-61.2%). The odds of assessment were lower for socially vulnerable children, namely, those from the lowest vs highest neighborhood income quintile (aOR, 0.84; 95% CI, 0.83-0.85), those born to refugee vs nonimmigrant mothers (aOR, 0.90; 95% CI, 0.88-0.93), and to teenaged mothers (aOR, 0.70; 95% CI, 0.69-0.71)). Children were more likely to have had developmental screening if cared for by a pediatrician vs family physician (aOR, 1.28; 95% CI, 1.13-1.44), recently trained physician (aOR, 1.38; 95% CI, 1.29-1.48 for ≤5 years in practice vs ≥21 years) and less likely if the physician was male (aOR, 0.64; 95% CI, 0.61-0.66). For physicians eligible for a pay-for-performance immunization bonus, there was a positive association with screening. CONCLUSIONS: In the context of a universal healthcare system and a specific financial incentive, uptake of the developmental assessment increased over time but remains moderate. The implementation of similar interventions or incentives needs to account for physician factors and focus on socially vulnerable children to be effective.

MS risk in immigrants in the McDonald era: A population-based study in Ontario, Canada.

OBJECTIVE: To determine risk factors for multiple sclerosis (MS) in immigrants and to compare MS risk in immigrants and long-term residents in Ontario, Canada. METHODS: We applied a validated algorithm to linked, population-based immigration and health claims data to identify incident cases of MS in immigrants and long-term residents between 1994 and 2016. We conducted 2 multivariable Cox proportional hazards regression analyses: 1 analysis limited to the immigrant cohort assessing potential risk factors for developing MS, and 1 analysis comparing MS risk between immigrants and matched long-term residents (1:3 match). RESULTS: We identified 2,304,302 immigrants for the immigrant-only analysis, of whom 1,526 (0.066%) developed MS. Risk was greatest in those <15 years old at landing (referent <15 years; 16-30 years: hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.63-0.85; 31-45 years: HR 0.55, 95% CI 0.47-0.64). Immigrants from the Middle East (HR 1.22, 95% CI 1.06-1.40) were at greater MS risk than immigrants from Western nations; all other regions had lower risk (p < 0.0001). The matched analysis included 2,207,751 immigrants and 6,362,169 long-term residents. Immigrants were less likely to develop MS than long-term residents (p < 0.0001), although this lower risk was attenuated with longer residence in Canada. CONCLUSIONS: MS incidence in immigrants to Ontario, Canada, varied widely by region of origin, with greatest risk seen in those from the Middle East. Longer residence in Canada was associated with increased risk, even with migration in adulthood, suggesting that environmental exposures into adulthood contribute to MS risk.

Use of the emergency department as a first point of contact for mental health care by immigrant youth in Canada: a population-based study.

BACKGROUND: Emergency department visits as a first point of contact for people with mental illness may reflect poor access to timely outpatient mental health care. We sought to determine the extent to which immigrants use the emergency department as an entryway into mental health services. METHODS: We used linked health and demographic administrative data sets to design a population-based cohort study. We included youth (aged 10-24 yr) with an incident mental health emergency department visit from 2010 to 2014 in Ontario, Canada (n = 118 851). The main outcome measure was an emergency department visit for mental health reasons without prior mental health care from a physician on an outpatient basis. The main predictor of interest was immigrant status (refugee, non-refugee immigrant and non-immigrant). Immigrant-specific predictors included time since migration, and region and country of origin. We used Poisson models to estimate adjusted rate ratios (aRRs) and 95% confidence intervals (CIs). RESULTS: The cohort included 2194 (1.8%) refugee, 6680 (5.6%) non-refugee immigrant and 109 977 (92.5%) nonimmigrant youth. Rates of first mental health contact in the emergency department were higher among refugee (61.3%) and non-refugee immigrant youth (57.6%) than non-immigrant youth (51.3%) (refugee aRR 1.17, 95% CI 1.13-1.21; non-refugee immigrant aRR 1.10, 95% CI 1.08-1.13). Compared with non-refugee immigrants, refugees had a higher rate of first mental health contact in the emergency department (aRR 1.06, 95% CI 1.02-1.11). We also observed higher rates among recent versus longer-term immigrants (aRR 1.10, 95% CI 1.05-1.16) and immigrants from Central America (aRR 1.17, 95% CI 1.08-1.26) and Africa (aRR 1.15, 95% CI 1.06-1.24) versus from North America and Western Europe. INTERPRETATION: Immigrant youth are more likely to present with a first mental health crisis to the emergency department than non-immigrants, with variability by region of origin and time since migration. Immigrants may face barriers to access and use of outpatient mental health services from a physician. Efforts are needed to reduce stigma and identify mental health problems early, before crisis, among immigrant populations.

Frailty and Potentially Inappropriate Medication Use at Nursing Home Transition.

BACKGROUND/OBJECTIVES: To estimate the prevalence of potentially inappropriate medication (PIM) use among older adults with cognitive impairment or dementia prior to and following admission to nursing homes and in relation to frailty. DESIGN: Retrospective cohort study using health administrative databases. SETTING: Ontario, Canada. PARTICIPANTS: 41,351 individuals with cognitive impairment or dementia, aged 66+ years newly admitted to nursing home between 2011 and 2014. MEASUREMENTS: PIMs were defined with 2015 Beers Criteria and included antipsychotics, H2 -receptor antagonists, benzodiazepines, and drugs with strong anticholinergic properties. Medication information was obtained at nursing home admission and in the subsequent 180 days. Multivariable Cox proportional-hazards models were used to assess the impact of frailty status (determined by a 72-item frailty index) on the hazard of starting and discontinuing PIMs. RESULTS: At admission, 44% of residents with cognitive impairment or dementia were on a PIM and prevalence varied by frailty (38.7% non-frail, 42.8% pre-frail, and 48.1% frail, P < .001). Following admission, many residents discontinued PIMs (23.5% for antipsychotics, 49.3% benzodiazepines, 32.2% anticholinergics, and 30.9% H2 -receptor antagonists). However, PIMs were also introduced with 10.9% newly started on antipsychotics, benzodiazepines (10.1%), anticholinergics (6.6%), and H2 -receptor antagonists (1.2%). After adjustment for other characteristics, frail residents had a similar risk of PIM discontinuation as non-frail residents except for anticholinergics (HR = 1.21, 95% CI 1.06-1.39) but were more likely to be newly prescribed benzodiazepines (HR = 1.32, 95% CI 1.20-1.44), antipsychotics (HR = 1.36, 1.23-1.49), and anticholinergics (HR = 1.34, 95% CI 1.20-1.50). CONCLUSION: Many residents with cognitive impairment or dementia enter nursing homes on PIMs. PIMs are more likely to be started in frail individuals following admission. Interventions to support deprescribing of PIMs should be implemented targeting frail individuals during the transition to nursing home.