Mental health sequelae in survivors of cardiogenic shock complicating myocardial infarction. A population-based cohort study.

PURPOSE: Cardiogenic shock secondary to acute myocardial infarction (AMI-CS) is associated with substantial short- and long-term morbidity and mortality. However, there are limited data on mental health sequelae that survivors experience following discharge. METHODS: We conducted a retrospective, population-based cohort study in Ontario, Canada of critically ill adult (≥ 18 years) survivors of AMI-CS, admitted to hospital between April 1, 2009 and March 31, 2019. We compared these patients to AMI survivors without shock. We captured outcome data using linked health administrative databases. The primary outcome was a new mental health diagnosis (a composite of mood, anxiety, or related disorders; schizophrenia/psychotic disorders; and other mental health disorders) following hospital discharge. We secondarily evaluated incidence of deliberate self-harm and death by suicide. We compared patients using overlap propensity score-weighted, cause-specific proportional hazard models. RESULTS: We included 7812 consecutive survivors of AMI-CS, from 135 centers. Mean age was 68.4 (standard deviation (SD) 12.2) years, and 70.3% were male. Median follow-up time was 767 days (interquartile range (IQR) 225-1682). Incidence of new mental health diagnosis among AMI-CS survivors was 109.6 per 1,000 person-years (95% confidence interval (CI) 105.4-113.9), compared with 103.8 per 1000 person-years (95% CI 102.5-105.2) among AMI survivors without shock. After propensity score adjustment, there was no difference in the risk of new mental health diagnoses following discharge [hazard ratio (HR) 0.99 (95% CI 0.94-1.03)]. Factors associated with new mental health diagnoses following AMI-CS included female sex, pre-existing mental health diagnoses, and discharge to a long-term hospital or rehabilitation institute. CONCLUSION: Survivors of AMI-CS experience substantial mental health morbidity following discharge. Risk of new mental health diagnoses was comparable between survivors of AMI with and without shock. Future research on interventions to mitigate psychiatric sequelae after AMI-CS is warranted.

Associations of preoperative anaemia with healthcare resource use and outcomes after colorectal surgery: a population-based cohort study.

BACKGROUND: Preoperative anaemia is common in patient undergoing colorectal surgery. Understanding the population-level costs of preoperative anaemia will inform development and evaluation of anaemia management at health system levels. METHODS: This was a population-based cohort study using linked, routinely collected data, including residents from Ontario, Canada, aged ≥18 yr who underwent an elective colorectal resection between 2012 and 2022. Primary exposure was preoperative anaemia (haemoglobin <130 g L-1 in males; <120 g L-1 in females). Primary outcome was 30-day costs in 2022 Canadian dollars (CAD), from the perspective of a publicly funded healthcare system. Secondary outcomes included red blood cell transfusion, major adverse events (MAEs), length of stay (LOS), days alive at home (DAH), and readmissions. RESULTS: We included 54,286 patients, with mean 65.3 (range 18-102) years of age and 49.0% females, among which 21 264 (39.2%) had preoperative anaemia. There was an absolute adjusted cost increase of $2671 per person at 30 days after surgery attributable to preoperative anaemia (ratio of means [RoM] 1.05, 95% confidence interval [CI] 1.04-1.06). Compared with the control group, 30-day risks of transfusion (odds ratio [OR] 4.34, 95% CI 4.04-4.66), MAEs (OR 1.14, 95% CI 1.03-1.27), LOS (RoM 1.08, 95% CI 1.07-1.10), and readmissions (OR 1.16, 95% CI 1.08-1.24) were higher in the anaemia group, with reduced DAH (RoM 0.95, 95% CI 0.95-0.96). CONCLUSIONS: Approximately $2671 CAD per person in 30-day health system costs are attributable to preoperative anaemia after colorectal surgery in Ontario, Canada.

Obstructive Sleep Apnea and Mental Health Disorders in the Pediatric Population: A Retrospective Population-based Cohort Study.

RATIONALE: Information is limited about the association between obstructive sleep apnea (OSA) and mental disorders in children. OBJECTIVES: In children, (1) to evaluate the association between OSA and new mental healthcare encounters; (2) to compare mental healthcare encounters two years post- to pre-OSA treatment initiation. METHODS: We conducted a retrospective longitudinal cohort study using Ontario health administrative data (Canada). Children (0-18 years) who underwent diagnostic polysomnography (PSG) 2009-2016 and met criteria for definition of moderate-severe OSA (PSG-OSA) were propensity score weighted by baseline characteristics and compared to children who underwent a PSG in the same period but did not meet the OSA definition (PSG-No-OSA). Children were followed until March 2021. Weighted cause-specific Cox Proportional Hazards and Modified Poisson regression models were used to compare time from PSG to first mental healthcare encounter and frequency of new mental healthcare encounters per person time, respectively. Among those who underwent adenotonsillectomy (AT) or were prescribed and claimed positive airway pressure therapy (PAP), we used age-adjusted conditional logistic regression models to compare two years post- to pre-treatment odds of mental healthcare encounters. RESULTS: Of 32,791 children analyzed, 7,724 (23.6%) children met criteria for moderate-severe OSA. In PSG-OSA group, 7,080 (91.7%) were treated (AT or PAP). Compared to PSG-No-OSA, the PSG-OSA group had a shorter time from PSG to first mental healthcare encounter (HR: 1.08; 95%CI: 1.05-1.12), but less frequent mental healthcare encounters in follow-up (RR: 0.92; 95% CI: 0.87-0.97). OSA treatment (AT or PAP) was associated with lower odds of mental healthcare encounters two years post-treatment initiation compared to two years prior (OR: 0.69; 95% CI: 0.65-0.74). CONCLUSION: In this large population-based study of children who underwent PSG for sleep disorder assessment, OSA diagnosis/treatment was associated with an improvement in some mental health indicators, such as fewer new mental healthcare encounters compared to no OSA, and lower odds of mental healthcare encounters compared to pre-OSA treatment.

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

OBJECTIVE: We conducted a retrospective cohort study to explore the relationship between chronotype measured by the total Morningness-Eveningness Questionnaire (MEQ) score and incident cancer. METHODS: We used clinical and provincial health administrative data on consecutive adults who underwent a Level 1 Polysomnography (PSG) and completed the MEQ between 2010 and 2015 in an academic hospital (Ontario, Canada) and were cancer-free at baseline. Cancer status was derived from the Ontario Cancer Registry. Individuals were followed until death or March 31, 2020. We used multivariable Cox cause-specific regressions to address the research objective. RESULTS: Of 3,004 individuals, 1,781 were analyzed: a median age of 54 years (IQR: 40-64) and 838 (47.1%) men. The median total MEQ score was 63 (IQR: 55-69); 61 (3.4%) were classified as evening (≤41), 536 (30.1%) as intermediate (42-58), and 1,184 (66.5%) as morning chronotypes (≥59). Over a median of 7 years (IQR: 5-8), 120 (6.7%) developed cancer. A U-shape relationship was found between the total MEQ score and an increased hazard of incident cancer, controlling for PSG measures of sleep apnea severity and sleep architecture, demographics, and comorbidities. Compared to the median of 63.0, a total MEQ score greater or less than the median was associated with an increased hazard of incident cancer, with the largest effect for those with a total score ≥76 (e.g., HR of a MEQ total score of 78 vs. 63: 2.01, 95% CI: 1.09-3.71). CONCLUSION: The U-shaped curve may reflect deviations from a standard circadian tendency, which may stress biological systems and influence malignancy risk.

A quasi-experimental evaluation of the association between implementation of Quality-Based Procedures funding for hip fractures and improvements in processes and outcomes for hip fracture patients in Ontario: an interrupted time series analysis.

PURPOSE: In 2013, Ontario introduced a patient-based funding model for hip fracture care (Quality-Based Procedures [QBP]). The association of QBP implementation with changes in processes and outcomes has not been evaluated. METHODS: We conducted a quasi-experimental study using linked health data for adult hip fractures as an interrupted time series. The pre-QBP period was from 2008 to 2012 and the post-QBP period was from 2014 to 2018; 2013 was excluded as a wash-in period. We used segmented regression analyses to estimate the association of QBP implementation with changes in processes (surgery in less than two days from admission, use of echocardiography, use of nerve blocks, and provision of geriatric care) and clinical outcomes (90-day mortality, 90-day readmissions, length of stay, and days alive at home). We estimated the immediate (level) change, trend (slope) postimplementation, and total counterfactual differences. Sensitivity analyses included case-mix adjustment and stratification by hospital type and procedure. RESULTS: We identified 45,500 patients in the pre-QBP period and 41,256 patients in the post-QBP period. There was a significant total counterfactual increase in the use of nerve blocks (11.1%; 95% confidence interval [CI], 6.2 to 16.0) and a decrease in the use of echocardiography (-2.5%; 95% CI, -3.7 to -1.3) after QBP implementation. The implementation of QBP was not associated with a clinically or statistically meaningful change in 90-day mortality, 90-day readmission, length of stay, or number of days alive at home. CONCLUSION: Evaluation of the QBP program is crucial to inform ongoing and future changes to policy and funding for hip fracture care. The introduction of the QBP Hip Fracture program, supported by evidence-based recommendations, was associated with improved application of some evidence-based processes of care but no changes in clinical outcomes. There is a need for ongoing development and evaluation of funding models to identify optimal strategies to improve the value and outcomes of hip fracture care. STUDY REGISTRATION: Open Science Framework ( https://osf.io/2938h/ ); first posted 13 June 2022.

RéSUMé: OBJECTIF: En 2013, l'Ontario a mis en place un modèle de financement axé sur les patient·es pour les soins suivant une fracture de la hanche (procédures fondées sur la qualité [PFQ]). L'association entre la mise en œuvre des PFQ et les changements dans les processus et les devenirs n'a pas été évaluée. MéTHODE: Nous avons mené une étude quasi expérimentale en utilisant des données de santé couplées pour les fractures de la hanche chez l'adulte comme une série chronologique interrompue. La période précédant les PFQ s'étendait de 2008 à 2012, et la période subséquente à l'implantation des PFQ allait de 2014 à 2018. L'année 2013 a été exclue en tant que période de rodage. Nous avons utilisé des analyses de régression segmentées pour estimer l'association entre la mise en œuvre des PFQ avec des changements aux processus (chirurgie en moins que deux jours suivant l'admission, utilisation de l'échocardiographie, utilisation de blocs nerveux et prestation de soins gériatriques) et des issues cliniques (mortalité à 90 jours, réadmissions à 90 jours, durée de séjour et jours de vie à domicile). Nous avons estimé le changement immédiat (niveau), la tendance (pente) après la mise en œuvre et les différences contrefactuelles totales. Les analyses de sensibilité comprenaient l'ajustement et la stratification de la combinaison de cas par type d'hôpital et par procédure. RéSULTATS: Nous avons identifié 45 500 patient·es dans la période pré-PFQ et 41 256 patient·es dans la période post-PFQ. Il y a eu une augmentation contrefactuelle totale significative de l'utilisation de blocs nerveux (11,1 %; intervalle de confiance [IC] à 95 %, 6,2 à 16,0) et une diminution de l'utilisation de l'échocardiographie (−2,5 %; IC 95 %, −3,7 à −1,3) après la mise en œuvre des PFQ. La mise en œuvre des PFQ n'a pas été associée à un changement cliniquement ou statistiquement significatif de la mortalité à 90 jours, de la réadmission à 90 jours, de la durée de séjour ou du nombre de jours de vie à domicile. CONCLUSION: L'évaluation du programme de PFQ est cruciale pour guider les changements actuels et futurs aux politiques et au financement des soins suivant une fracture de la hanche. La mise en place du programme de PFQ pour les fractures de la hanche, appuyée par des recommandations fondées sur des données probantes, a été associée à une meilleure application de certains processus de soins fondés sur des données probantes, mais à aucun changement dans les devenirs cliniques. Il est nécessaire d'élaborer et d'évaluer continuellement des modèles de financement afin de déterminer les stratégies optimales pour améliorer la valeur et les devenirs des soins suivant une fracture de la hanche. ENREGISTREMENT DE L'éTUDE: Open Science Framework ( https://osf.io/2938h/ ); première publication le 13 juin 2022.

Residential surrounding greenness and the incidence of childhood asthma: Findings from a population-based cohort in Ontario, Canada.

Several epidemiological studies have investigated the possible role that living in areas with greater amounts of greenspace has on the incidence of childhood asthma. These findings have been inconsistent, and few studies explored the relevance of timing of exposure. We investigated the role of residential surrounding greenness on the risk of incident asthma using a population-based retrospective cohort study. We included 982,131 singleton births in Ontario, Canada between 2006 and 2013. Two measures of greenness, the Normalized Difference Vegetation Index (NDVI) and the Green View Index (GVI), were assigned to the residential histories of these infants from pregnancy through to 12 years of age. Longitudinally-based diagnoses of asthma were determined by using provincial administrative health data. The extended Cox hazards model was used to characterize associations between greenness measures and asthma (up to age 12 years) while adjusting for several risk factors. In a fully adjusted model, that included a term for traffic-related air pollution (NO2), we found no association between an interquartile range increase (0.08) of the NDVI during childhood and asthma incidence (HR = 0.99; 95 % CI = 0.99-1.01). In contrast, we found that an 0.08 increase in NDVI during childhood reduced the risk of asthma in children 7-12 years of age by 14 % (HR = 0.86, 95 % CI:0.79-0.95). Seasonal differences in the association between greenness and asthma were noted. Our findings suggest that residential proximity to greenness reduces the risk of asthma in children aged 7-12.

Changes in Cannabis-Attributable Hospitalizations Following Nonmedical Cannabis Legalization in Canada.

Importance: The impact of adult-use cannabis legalization and subsequent commercialization (ie, increasing store and product access) on hospitalizations in Canada is unclear. Objectives: To examine changes in overall and subtypes of hospitalizations due to cannabis and associated factors following legalization in Canada and to compare changes between provinces. Design, Setting, and Participants: This repeated cross-sectional analysis included all acute hospitalizations for individuals aged 15 to 105 years in Canada's 4 most populous provinces (Ontario, Quebec, Alberta and British Columbia, population 26.9 million individuals in 2018). Data were obtained from routinely collected health administrative databases. Immediate and gradual changes in the age- and sex-standardized rates of hospitalizations due to cannabis were compared using an interrupted time series design over 3 time periods: prelegalization (January 2015 to September 2018), legalization with product and store restrictions (October 2018 to February 2020), and commercialization, which overlapped with the COVID-19 pandemic (March 2020 to March 2021). Main Outcomes and Measures: Rates of hospitalizations due to cannabis per 100 000 individuals and per 1000 all-cause hospital admissions. Results: There were 105 203 hospitalizations due to cannabis over the 7-year study period, 69 192 of which (65.8%) were among male individuals, and 34 678 (33%) of which were among individuals aged 15 to 24 years. Overall, the age- and sex-standardized rate of hospitalizations increased 1.62 times between January 2015 (3.99 per 100 000 individuals) and March 2021 (6.46 per 100 000 individuals). The largest relative increase in hospitalizations was for cannabis-induced psychosis (rate ratio, 1.40; 95% CI, 1.34 to 1.47 during the commercialization period relative to the prelegalization period). Nationally, legalization with restrictions was associated with a gradual monthly decrease of -0.06 (95% CI -0.08 to -0.03) in hospitalizations due to cannabis per 100 000 individuals. Commercialization and the COVID-19 pandemic were associated with an immediate increase of 0.83 (95% CI, 0.30 to 1.30) hospitalizations due to cannabis per 100 000 individuals. There was provincial variation in changes, with provinces with less mature legal markets experiencing the greatest declines immediately following legalization. Conclusions and Relevance: This cross-sectional study found that legalization with restrictions was not associated with an increase in hospitalizations due to cannabis but commercialization was. The findings suggest that commercialization of cannabis may be associated with increases in cannabis-related health harms, including cannabis-induced psychosis.

Screening for postpartum depression and risk of suicidality with obstetrical patients: a cross-sectional survey.

BACKGROUND: Pregnancy is a vulnerable time where the physical and social stress of the COVID-19 pandemic affects psychological health, including postpartum depression (PPD). This study is designed to estimate the prevalence and correlates of PPD and risk of suicidality among individuals who gave birth during the COVID-19 pandemic. METHODS: We surveyed individuals who gave birth at The Ottawa Hospital and were ≥ 20 days postpartum, between March 17 and June 16, 2020. A PPD screen consisted of a score ≥ 13 using the Edinburgh Postnatal Depression Scale. A score of 1, 2, or 3 on item 10 ("The thought of harming myself has occurred to me") indicates risk of suicidality. If a participant scores greater than ≥ 13 or ≥ 1 on item 10 they were flagged for PPD, the Principal Investigator (DEC) was notified within 24 h of survey completion for a chart review and to assure follow-up. Modified Poisson multivariable regression models were used to identify factors associated with PPD and risk of suicidality using adjusted risk ratios (aRR) and 95% confidence intervals (CI). RESULTS: Of the 216 respondents, 64 (30%) screened positive for PPD and 17 (8%) screened positive for risk of suicidality. The maternal median age of the total sample was 33 years (IQR: 30-36) and the infant median age at the time of the survey was 76 days (IQR: 66-90). Most participants reported some form of positive coping strategies during the pandemic (97%) (e.g. connecting with friends and family, exercising, getting professional help) and 139 (64%) reported negative coping patterns (e.g. over/under eating, sleep problems). In total, 47 (22%) had pre-pregnancy anxiety and/or depression. Negative coping (aRR:2.90, 95% CI: 1.56-5.37) and pre-existing anxiety/depression (aRR:2.03, 95% CI:1.32-3.11) were associated with PPD. Pre-existing anxiety/depression (aRR:3.16, 95% CI:1.28-7.81) was associated with risk of suicidality. CONCLUSIONS: Almost a third of participants in this study screened positive for PPD and 8% for risk of suicidality. Mental health screening and techniques to foster positive coping skills/strategies are important areas to optimize postpartum mental health.

Long-Term Outcomes of Cardiogenic Shock Complicating Myocardial Infarction.

BACKGROUND: Cardiogenic shock secondary to acute myocardial infarction (AMI-CS) is associated with substantial short-term mortality; however, there are limited data on long-term outcomes and trends. OBJECTIVES: This study sought to examine long-term outcomes of AMI-CS patients. METHODS: This was a population-based, retrospective cohort study in Ontario, Canada of critically ill adult patients with AMI-CS who were admitted to hospitals between April 1, 2009 and March 31, 2019. Outcome data were captured using linked health administrative databases. RESULTS: A total of 9,789 consecutive patients with AMI-CS from 135 centers were included. The mean age was 70.5 ± 12.3 years, and 67.7% were male. The incidence of AMI-CS was 8.2 per 100,000 person-years, and it increased over the study period. Critical care interventions were common, with 5,422 (55.4%) undergoing invasive mechanical ventilation, 1,425 (14.6%) undergoing renal replacement therapy, and 1,484 (15.2%) receiving mechanical circulatory support. A total of 2,961 patients (30.2%) died in the hospital, and 4,004 (40.9%) died by 1 year. Mortality at 5 years was 58.9%. Small improvements in short- and long-term mortality were seen over the study period. Among survivors to discharge, 2,870 (42.0%) required increased support in care from their preadmission baseline, 3,244 (47.5%) were readmitted to the hospital within 1 year, and 1,047 (15.3%) died within 1 year. The mean number of days at home in the year following discharge was 307.9 ± 109.6. CONCLUSIONS: Short- and long-term mortality among patients with AMI-CS is high, with minimal improvement over time. AMI-CS survivors experience significant morbidity, with high risks of readmission and death. Future studies should evaluate interventions to minimize postdischarge morbidity and mortality among AMI-CS survivors.

Attributable Perioperative Cost of Frailty after Major, Elective Noncardiac Surgery: A Population-based Cohort Study.

BACKGROUND: Patients with frailty consistently experience higher rates of perioperative morbidity and mortality; however, costs attributable to frailty remain poorly defined. This study sought to identify older patients with and without frailty using a validated, multidimensional frailty index and estimated the attributable costs in the year after major, elective noncardiac surgery. METHODS: The authors conducted a retrospective population-based cohort study of all patients 66 yr or older having major, elective noncardiac surgery between April 1, 2012, and March 31, 2018, using linked health data obtained from an independent research institute (ICES) in Ontario, Canada. All data were collected using standard methods from the date of surgery to the end of 1-yr follow-up. The presence or absence of preoperative frailty was determined using a multidimensional frailty index. The primary outcome was total health system costs in the year after surgery using a validated patient-level costing method capturing direct and indirect costs. Secondary outcomes included costs to postoperative days 30 and 90 along with sensitivity analyses and evaluation of effect modifiers. RESULTS: Of 171,576 patients, 23,219 (13.5%) were identified with preoperative frailty. Unadjusted costs were higher among patients with frailty (ratio of means 1.79, 95% CI 1.76 to 1.83). After adjusting for confounders, an absolute cost increase of $11,828 Canadian dollar (ratio of means 1.53; 95% CI, 1.51 to 1.56) was attributable to frailty. This association was attenuated with additional control for comorbidities (ratio of means 1.24, 95% CI, 1.22 to 1.26). Among contributors to total costs, frailty was most strongly associated with increased postacute care costs. CONCLUSIONS: For patients with preoperative frailty having elective surgery, the authors estimate that attributable costs are increased 1.5-fold in the year after major, elective noncardiac surgery. These data inform resource allocation for patients with frailty.

Critical windows of exposure to air pollution and gestational diabetes: assessing effect modification by maternal pre-existing conditions and environmental factors.

BACKGROUND: Ambient air pollution has been associated with gestational diabetes (GD), but critical windows of exposure and whether maternal pre-existing conditions and other environmental factors modify the associations remains inconclusive. METHODS: We conducted a retrospective cohort study of all singleton live birth that occurred between April 1st 2006 and March 31st 2018 in Ontario, Canada. Ambient air pollution data (i.e., fine particulate matter with a diameter ≤ 2.5 µm (PM2.5), nitrogen dioxide (NO2) and ozone (O3)) were assigned to the study population in spatial resolution of approximately 1 km × 1 km. The Normalized Difference Vegetation Index (NDVI) and the Green View Index (GVI) were also used to characterize residential exposure to green space as well as the Active Living Environments (ALE) index to represent the active living friendliness. Multivariable Cox proportional hazards regression models were used to evaluate the associations. RESULTS: Among 1,310,807 pregnant individuals, 68,860 incident cases of GD were identified. We found the strongest associations between PM2.5 and GD in gestational weeks 7 to 18 (HR = 1.07 per IQR (2.7 µg/m3); 95% CI: 1.02 - 1.11)). For O3, we found two sensitive windows of exposure, with increased risk in the preconception period (HR = 1.03 per IQR increase (7.0 ppb) (95% CI: 1.01 - 1.06)) as well as gestational weeks 9 to 28 (HR 1.08 per IQR (95% CI: 1.04 -1.12)). We found that women with asthma were more at risk of GD when exposed to increasing levels of O3 (p- value for effect modification = 0.04). Exposure to air pollutants explained 20.1%, 1.4% and 4.6% of the associations between GVI, NDVI and ALE, respectively. CONCLUSION: An increase of PM2.5 exposure in early pregnancy and of O3 exposure during late first trimester and over the second trimester of pregnancy were associated with gestational diabetes whereas exposure to green space may confer a protective effect.

Polysomnographic Assessment of Sleep Disturbances in Cancer Development: A Historical Multicenter Clinical Cohort Study.

BACKGROUND: Many cellular processes are controlled by sleep. Therefore, alterations in sleep might be expected to stress biological systems that could influence malignancy risk. RESEARCH QUESTION: What is the association between polysomnographic measures of sleep disturbances and incident cancer, and what is the validity of cluster analysis in identifying polysomnography phenotypes? STUDY DESIGN AND METHODS: We conducted a retrospective multicenter cohort study using linked clinical and provincial health administrative data on consecutive adults free of cancer at baseline with polysomnography data collected between 1994 and 2017 in four academic hospitals in Ontario, Canada. Cancer status was derived from registry records. Polysomnography phenotypes were identified by k-means cluster analysis. A combination of validation statistics and distinguishing polysomnographic features was used to select clusters. Cox cause-specific regressions were used to assess the relationship between identified clusters and incident cancer. RESULTS: Among 29,907 individuals, 2,514 (8.4%) received a diagnosis of cancer over a median of 8.0 years (interquartile range, 4.2-13.5 years). Five clusters were identified: mild (mildly abnormal polysomnography findings), poor sleep, severe OSA or sleep fragmentation, severe desaturations, and periodic limb movements of sleep (PLMS). The associations between cancer and all clusters compared with the mild cluster were significant while controlling for clinic and year of polysomnography. When additionally controlling for age and sex, the effect remained significant only for PLMS (adjusted hazard ratio [aHR], 1.26; 95% CI, 1.06-1.50) and severe desaturations (aHR, 1.32; 95% CI, 1.04-1.66). Further controlling for confounders, the effect remained significant for PLMS, but was attenuated for severe desaturations. INTERPRETATION: In a large cohort, we confirmed the importance of polysomnographic phenotypes and highlighted the role that PLMS and oxygenation desaturation may play in cancer. Using this study's findings, we also developed an Excel (Microsoft) spreadsheet (polysomnography cluster classifier) that can be used to validate the identified clusters on new data or to identify which cluster a patient belongs to. TRIAL REGISTRY: ClinicalTrials.gov; Nos.: NCT03383354 and NCT03834792; URL: www. CLINICALTRIALS: gov.

Pediatric Hospitalizations for Unintentional Cannabis Poisonings and All-Cause Poisonings Associated With Edible Cannabis Product Legalization and Sales in Canada.

Importance: Canada legalized cannabis in October 2018 but initially prohibited the sale of edibles (eg, prepackaged candies). Starting in January 2020, some provinces permitted the sale of commercial cannabis edibles. The association of legalizing cannabis edibles with unintentional pediatric poisonings is uncertain. Objective: To evaluate changes in proportions of all-cause hospitalizations for poisoning due to cannabis in children during 3 legalization policy periods in Canada's 4 most populous provinces (including 3.4 million children aged 0-9 years). Design, Setting, and Participants: This repeated cross-sectional study included all hospitalizations in children aged 0 to 9 years in Ontario, Alberta, British Columbia, and Quebec between January 1, 2015, and September 30, 2021. Exposures: Prelegalization (January 2015 to September 2018); period 1, in which dried flower only was legalized in all provinces (October 2018 to December 2019); and period 2, in which edibles were legalized in 3 provinces (exposed provinces) and restricted in 1 province (control province) (January 2020 to September 2021). Main Outcomes and Measures: The primary outcome was the proportion of hospitalizations due to cannabis poisoning out of all-cause poisoning hospitalizations. Data analysis was performed using descriptive statistics and Poisson regression models. Results: During the 7-year study period, there were 581 pediatric hospitalizations for cannabis poisoning (313 [53.9%] boys; 268 [46.1%] girls; mean [SD] age, 3.6 [2.5] years) and 4406 hospitalizations for all-cause poisonings. Of all-cause poisoning hospitalizations, the rate per 1000 due to cannabis poisoning before legalization was 57.42 in the exposed provinces and 38.50 in the control province. During period 1, the rate per 1000 poisoning hospitalizations increased to 149.71 in the exposed provinces (incidence rate ratio [IRR], 2.55; 95% CI, 1.88-3.46) and to 117.52 in the control province (IRR, 3.05; 95% CI, 1.82-5.11). During period 2, the rate per 1000 poisoning hospitalizations due to cannabis more than doubled to 318.04 in the exposed provinces (IRR, 2.16; 95% CI, 1.68-2.80) but remained similar at 137.93 in the control province (IRR, 1.18; 95% CI, 0.71-1.97). Conclusions and Relevance: This cross-sectional study found that following cannabis legalization, provinces that permitted edible cannabis sales experienced much larger increases in hospitalizations for unintentional pediatric poisonings than the province that prohibited cannabis edibles. In provinces with legal edibles, approximately one-third of pediatric hospitalizations for poisonings were due to cannabis. These findings suggest that restricting the sale of legal commercial edibles may be key to preventing pediatric poisonings after recreational cannabis legalization.

Association of clinically significant obstructive sleep apnoea with risks of contracting COVID-19 and serious COVID-19 complications: a retrospective population-based study of health administrative data.

RATIONALE/OBJECTIVES: Despite plausible pathophysiological mechanisms, more research is needed to confirm the relationship between obstructive sleep apnoea (OSA) and the risk of COVID-19 infection or COVID-19-related serious complications. METHODS: We conducted a retrospective population-based cohort study using provincial health administrative data (Ontario, Canada). Adults with physician-diagnosed OSA who received positive airway pressure therapy in the 5 years prepandemic (OSA group) were propensity score matched by baseline characteristics to individuals in the general population at low risk of OSA (non-OSA group) using inverse probability of treatment weighting. Weighted HRs of (1) a positive COVID-19 test and (2) COVID-19-related emergency department (ED) visits, hospitalisations, intensive care unit (ICU) admissions and mortality, within 12 months of pandemic onset, were compared between groups. We also evaluated the impact of comorbid cardiometabolic or chronic airways disease. RESULTS: We identified and matched 324 029 individuals in the OSA group to 4 588 200 individuals in the non-OSA group. Compared with the non-OSA group, those in the OSA group were at a greater hazard of testing positive for COVID-19 (HR=1.17, 95% CI 1.13 to 1.21), having a COVID-19-related ED visit (HR=1.62, 95% CI 1.51 to 1.73), hospitalisation (HR=1.50, 95% CI 1.37 to 1.65) or ICU admission (HR=1.53, 95% CI 1.27 to 1.84). COVID-19-related 30-day mortality was not different (HR=0.98, 95% CI 0.82 to 1.16).We found that for the OSA group, comorbid airways disease but not cardiometabolic conditions increased the hazards of COVID-19-related outcomes, including mortality. CONCLUSION: In this large population-based study, we demonstrated that a recent diagnosis of OSA requiring treatment was associated with an increased hazard of testing positive for COVID-19 and serious COVID-19-related complications, particularly in those with co-existing chronic airways disease.

Outpatient Mental Health Follow-up and Recurrent Self-harm and Suicide Among Patients Admitted to the ICU for Self-harm: A Population-based Cohort Study.

BACKGROUND: Patients surviving an ICU admission for deliberate self-harm are at high risk of recurrent self-harm or suicide after discharge. It is unknown whether mental health follow-up after discharge (with either a family physician or psychiatrist) reduces this risk. RESEARCH QUESTION: What is the association between mental health follow-up after discharge and recurrent self-harm among patients admitted to the ICU for intentional self-harm? STUDY DESIGN AND METHODS: Population-based cohort study of consecutive adults (≥ 18 years of age) from Ontario, Canada, who were admitted to ICU because of intentional self-harm between 2009 and 2017. We categorized patients according to follow-up, with 'early follow-up' indicating 1 to 21 days after discharge, 'late follow-up' indicating 22 to 60 days after discharge, and 'no follow-up' indicating no follow-up within 60 days of discharge. We conducted analyses using a cause-specific extended Cox regression model to account for varying time for mental health follow-up relative to the outcomes of interest. The primary outcome was recurrent ICU admission for self-harm within 1 year of discharge. RESULTS: We included 9,569 consecutive adults admitted to the ICU for deliberate self-harm. Compared with receiving no mental health follow-up, both early follow-up (hazard ratio [HR], 1.37; 95% CI, 1.07-1.75) and late follow-up (HR, 1.69; 95% CI, 1.22-2.35) were associated with increased risk in recurrent ICU admission for self-harm. As compared with no follow-up, neither early follow-up (HR, 1.10; 95% CI, 0.70-1.73) nor late follow-up (HR, 1.54; 95% CI, 0.84-2.83) were associated with increased risk of death by suicide. INTERPREATION: Among adults admitted to the ICU for deliberate self-harm, mental health follow-up after discharge was not associated with reduced risk of recurrent ICU admission for self-harm or death resulting from suicide, and patients seeking outpatient follow-up may be those at highest risk of these outcomes. Future research should focus on additional and novel methods of risk mitigation in this vulnerable population.

Days alive and at home after hip fracture: a cross-sectional validation of a patient-centred outcome measure using routinely collected data.

BACKGROUND: Days alive and at home (DAH) is a patient centered outcome measureable in routinely collected health data. The validity and minimally important difference (MID) in hip fracture have not been evaluated. OBJECTIVE: We assessed construct and predictive validity and estimated a MID for the patient-centred outcome of DAH after hip fracture admission. METHODS: This is a cross-sectional observational study using linked health administrative data in Ontario, Canada. DAH was calculated as the number of days alive within 90 days of admission minus the number of days hospitalised or institutionalised. All hospital admissions (2012-2018) for hip fracture in adults aged >50 years were included. Construct validity analyses used Bayesian quantile regression to estimate the associations of postulated patient, admission and process-related variables with DAH. The predictive validity assessed was the correlation of DAH in 90 days with the value from 91 to 365 days; and the association and discrimination of DAH in 90 days predicting subsequent mortality. MID was estimated by averaging distribution-based and clinical anchor-based estimates. RESULTS: We identified 63 778 patients with hip fracture. The median number of DAH was 43 (range 0-87). In the 90 days after admission, 8050 (12.6%) people died; a further 6366 (10.0%) died from days 91 to 365. Associations between patient-level and admission-level factors with the median DAH (lower with greater age, frailty and comorbidity, lower if admitted to intensive care or having had a complication) supported construct validity. DAH in 90 days after admission was strongly correlated with DAH in 365 days after admission (r=0.922). An 11-day MID was estimated. CONCLUSION: DAH has face, construct and predictive validity as a patient-centred outcome in patients with hip fracture, with an estimated MID of 11 days. Future research is required to include direct patient perspectives in confirming MID.

Measuring the Predictive Accuracy of Preoperative Clinical Frailty Instruments Applied to Electronic Health Data in Older Patients Having Emergency General Surgery: A Retrospective Cohort Study.

OBJECTIVE: To compare predictive accuracy of frailty instruments operationalizable in electronic data for prognosticating outcomes among older adults undergoing emergency general surgery (EGS). BACKGROUND: Older patients undergoing EGS are at higher risk of perioperative morbidity and mortality. Preoperative frailty is a common and strong perioperative risk factor in this population. Despite this, existing barriers preclude routine preoperative frailty assessment. METHODS: We conducted a retrospective cohort study of adults above 65 undergoing EGS from 2012 to 2018 using Institute for Clinical Evaluative Sciences (ICES) provincial healthcare data in Ontario, Canada. We compared 4 frailty instruments: Frailty Index (FI), Hospital Frailty Risk Score (HFRS), Risk Analysis Index-Administrative (RAI), ACG Frailty-defining diagnoses indicator (ACG). We compared predictive accuracy beyond baseline risk models (age, sex, American Society of Anesthesiologists' score, procedural risk). Predictive performance was measured using discrimination, calibration, explained variance, net reclassification index and Brier score (binary outcomes); using explained variance, root mean squared error and mean absolute prediction error (continuous outcomes). Primary outcome was 30-day mortality. Secondary outcomes were 365-day mortality, nonhome discharge, days alive at home, length of stay, and 30-day and 365-day health systems cost. RESULTS: A total of 121,095 EGS patients met inclusion criteria. Of these, 11,422 (9.4%) experienced death 30 days postoperatively. Addition of FI, HFRS, and RAI to the baseline model led to improved discrimination, net reclassification index, and R2 ; RAI demonstrated the largest improvements. CONCLUSIONS: Adding 4 frailty instruments to typically assessed preoperative risk factors demonstrated strong predictive performance in accurately prognosticating perioperative outcomes. These findings can be considered in developing automated risk stratification systems among older EGS patients.

Population-Level Trends in Emergency Department Encounters for Sexual Assault Preceding and During the COVID-19 Pandemic Across Ontario, Canada.

Importance: Lockdown measures and the stress of the COVID-19 pandemic are factors associated with increased risk of violence, yet there is limited information on trends in emergency department (ED) encounters for sexual assault. Objective: To compare changes in ED encounters for sexual assault during the COVID-19 pandemic vs prepandemic estimates. Design, Setting, and Participants: This retrospective, population-based cohort study used linked health administrative data from 197 EDs across Ontario, Canada, representing more than 15 million residents. Participants included all patients who presented to an ED in Ontario from January 11, 2019, to September 10, 2021. Male and female individuals of all ages were included. Data analysis was performed from March to October 2022. Exposures: Sexual assault, defined through 27 International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, procedure and diagnoses codes. Main Outcomes and Measures: Ten bimonthly time periods were used to compare differences in the frequency and rates of ED encounters for sexual assault between 2020 to 2021 (during the pandemic) compared with baseline prepandemic rates in 2019. Rate differences (RDs) and age adjusted rate ratios (aRRs) and Wald 95% CIs were calculated using Poisson regression. Results: From January 11, 2019, to September 10, 2021, there were 14 476 656 ED encounters, including 10 523 for sexual assault (9304 [88.4%] among female individuals). The median (IQR) age was 23 (17-33) years for female individuals and 15 (4-29) years for male individuals. Two months before the pandemic, ED encounters increased for sexual assault among female individuals (8.4 vs 6.9 cases per 100 000; RD, 1.51 [95% CI, 1.06 to 1.96]; aRR, 1.22 [95% CI, 1.09 to 1.38]) and male individuals (1.2 vs 1.0 cases per 100 000; RD, 0.19 [95% CI, 0.05 to 0.36]; aRR, 1.19 [95% CI, 0.87 to 1.64]). During the first 2 months of the pandemic, the rates decreased for female individuals (4.2 vs 8.3 cases per 100 000; RD, -4.07 [95% CI, -4.48 to -3.67]; aRR, 0.51 [95% CI, 0.44 to 0.58]) and male individuals (0.5 vs 1.2 cases per 100 000; RD, -0.72 [95% CI, -0.86 to -0.57]; aRR, 0.39 [95% CI, 0.26 to 0.58]). For the remainder of the study period, the rates of sexual assault oscillated, returning to prepandemic levels during the summer months and between COVID-19 waves. Conclusions and Relevance: These findings suggest that lockdown protocols should evaluate the impact of limited care for sexual assault. Survivors should still present to EDs, especially when clinical care or legal interventions are needed.

Initial treatment is associated with improved survival and end-of-life outcomes for patients with pancreatic cancer: a cohort study.

BACKGROUND: We describe the association between initial treatment and end-of-life (EOL) outcomes among patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: This population-based cohort study included patients with PDAC who died from April 2010-December 2017 in Ontario, Canada using administrative databases. We used multivariable models to explore the association between index cancer treatment (no cancer-directed therapy, radiation, chemotherapy, surgery alone, and surgery and chemotherapy), and primary (mortality, healthcare encounters and palliative care) and secondary outcomes (location of death, hospitalizations, and receipt of chemotherapy within the last 30 days of life). RESULTS: In our cohort (N = 9950), 56% received no cancer-directed therapy, 5% underwent radiation, 27% underwent chemotherapy, 7% underwent surgery alone, and 6% underwent surgery and chemotherapy. Compared to no cancer-directed therapy, radiation therapy (HR = 0.63), chemotherapy (HR = 0.43) surgery alone (HR = 0.32), and surgery and chemotherapy (HR = 0.23) were all associated with decreased mortality. Radiation (AMD = - 3.64), chemotherapy (AMD = -6.35), surgery alone (AMD = -6.91), and surgery and chemotherapy (AMD = -6.74) were all associated with fewer healthcare encounters per 30 days in the last 6 months of life. Chemotherapy (AMD = -1.57), surgery alone (AMD = -1.65), and surgery and chemotherapy (AMD = -1.67) were associated with fewer palliative care visits (all p-values for estimates above < 0.05). Treatment groups were associated with lower odds of institutional death and hospitalization at EOL, and higher odds of chemotherapy at EOL. CONCLUSIONS: Receiving cancer-directed therapies was associated with higher survival, fewer healthcare visits, lower odds of dying in an institution and hospitalization at EOL, fewer palliative care visits, and higher odds of receiving chemotherapy at EOL.