Indolent lymphoma care delivery and outcomes during the COVID-19 pandemic in Ontario, Canada.

The treatment pattern and outcomes in patients with indolent B-cell lymphoma treated during the coronavirus disease 2019 (COVID-19) pandemic period compared to the prepandemic period are unclear. This was a retrospective population-based study using administrative databases in Ontario, Canada (follow-up to 31 March 2022). The primary outcome was treatment pattern; secondary outcomes were death, toxicities, healthcare utilization (emergency department [ED] visit, hospitalization) and SARS-CoV-2 outcomes. Adjusted hazard ratios (aHR) from Cox proportional hazards models were used to estimate associations. We identified 4143 patients (1079 pandemic, 3064 prepandemic), with a median age of 69 years. In both time periods, bendamustine (B) + rituximab (BR) was the most frequently prescribed regimen. During the pandemic, fewer patients received R maintenance or completed the full 2-year course (aHR 0.81, 95% CI 0.71-0.92, p = 0.001). Patients treated during the pandemic had less healthcare utilization (ED visit aHR 0.77, 95% CI 0.68, 0.88, p < 0.0001; hospitalization aHR 0.81, 95% CI 0.70-0.94, p = 0.0067) and complications (infection aHR 0.69, 95% CI 0.57-0.82, p < 0.0001; febrile neutropenia aHR 0.66, 95% CI 0.47-0.94, p = 0.020), with no difference in death. Independent of vaccination, active rituximab use was associated with a higher risk of COVID-19 complications. Despite similar front-line regimen use, healthcare utilization and admissions for infection were less in the pandemic cohort.

Short- and long-term outcomes of acute diverticulitis in patients with transplanted kidneys.

AIM: The safety of nonoperative treatment for patients with transplanted kidneys who develop acute diverticulitis is unclear. Our primary aim was to examine the long-term sequelae of nonoperative management in this group. METHOD: We performed a population-based retrospective cohort study using linked administrative databases housed at ICES in Ontario, Canada. We included adult (≥18 years) patients admitted with acute diverticulitis between April 2002 and December 2019. Patients with a functioning kidney transplant were compared with those without a transplant. The primary outcome was failure of conservative management (operation, drainage procedure or death due to acute diverticulitis) beyond 30 days. The cumulative incidence function and a Fine-Grey subdistribution hazard model were used to evaluate this outcome accounting for competing risks. RESULTS: We examined 165 patients with transplanted kidneys and 74 095 without. Patients with transplanted kidneys were managed conservatively 81% of the time at the index event versus 86% in nontransplant patients. Short-term outcomes were comparable, but cumulative failure of conservative management at 5 years occurred in 5.6% (95% CI 2.3%-11.1%) of patients with transplanted kidneys versus 2.1% (95% CI 2.0%-2.3%) in those without. Readmission for acute diverticulitis was also higher in transplanted patients at 5 years at 16.7% (95% CI 10.1%-24.7%) versus 11.6% (95% CI 11.3%-11.9%). Adjusted analyses showed increased failure of conservative management [subdistribution hazard ratio (sHR) 3.24, 95% CI 1.69-6.22] and readmissions (sHR 1.55, 95% CI 1.02-2.36) for patients with transplanted kidneys. CONCLUSION: Most patients with transplanted kidneys are managed conservatively for acute diverticulitis. Although long-term readmission and failure of conservative management is higher for this group than the nontransplant population, serious outcomes are infrequent, substantiating the safety of this approach.

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

BACKGROUND: International studies show that adults with intellectual and developmental disabilities (IDD) are disproportionately represented in the criminal justice and forensic mental health systems; however, it is difficult to capture their involvement across systems in any one jurisdiction. AIMS: The current study aimed to estimate the prevalence of IDD across different parts of the criminal justice and forensic mental health systems in Ontario and to describe the demographic and clinical profiles of these individuals relative to their counterparts without IDD. METHODS: This project utilised administrative data to identify and describe the demographic and clinical characteristics of adults with IDD and criminal justice or forensic involvement across four sectors: federal correctional facilities, provincial correctional facilities, forensic inpatient mental health care and community mental health programmes. Questions were driven by and results were contextualised by a project advisory group and people with lived experience from the different sectors studied, resulting in a series of recommendations. RESULTS: Adults with IDD were over-represented in each of the four settings, ranging from 2.1% in federal corrections to 16.7% in forensic inpatient care. Between 20% (forensic inpatient) and 38.4% (provincial corrections) were under the age of 25 and between 34.5% (forensic inpatient) and 41.8% (provincial corrections) resided in the lowest income neighbourhoods. Medical complexity and rates of co-occurring mental health conditions were higher for people with IDD than those without IDD in federal and provincial corrections. CONCLUSIONS: Establishing a population-based understanding of people with IDD within these sectors is an essential first step towards understanding and addressing service and care needs. Building on the perspectives of people who work in and use these systems, this paper concludes with intervention recommendations before, during and after justice involvement.

Differential Patterns by Area-Level Social Determinants of Health in Coronavirus Disease 2019 (COVID-19)-Related Mortality and Non-COVID-19 Mortality: A Population-Based Study of 11.8 Million People in Ontario, Canada.

BACKGROUND: Social determinants of health (SDOH) have been associated with coronavirus disease 2019 (COVID-19) outcomes. We examined patterns in COVID-19-related mortality by SDOH and compared these patterns to those for non-COVID-19 mortality. METHODS: Residents of Ontario, Canada, aged ≥20 years were followed from 1 March 2020 to 2 March 2021. COVID-19-related death was defined as death within 30 days following or 7 days prior to a positive COVID-19 test. Area-level SDOH from the 2016 census included median household income; proportion with diploma or higher educational attainment; proportion essential workers, racially minoritized groups, recent immigrants, apartment buildings, and high-density housing; and average household size. We examined associations between SDOH and COVID-19-related mortality, and non-COVID-19 mortality using cause-specific hazard models. RESULTS: Of 11 810 255 individuals, we observed 3880 COVID-19-related deaths and 88 107 non-COVID-19 deaths. After accounting for demographics, baseline health, and other area-level SDOH, the following were associated with increased hazards of COVID-19-related death (hazard ratio [95% confidence interval]: lower income (1.30 [1.04-1.62]), lower educational attainment (1.27 [1.07-1.52]), higher proportions essential workers (1.28 [1.05-1.57]), racially minoritized groups (1.42 [1.08-1.87]), apartment buildings (1.25 [1.07-1.46]), and large vs medium household size (1.30 [1.12-1.50]). Areas with higher proportion racially minoritized groups were associated with a lower hazard of non-COVID-19 mortality (0.88 [0.84-0.92]). CONCLUSIONS: Area-level SDOH are associated with COVID-19-related mortality after accounting for demographic and clinical factors. COVID-19 has reversed patterns of lower non-COVID-19 mortality among racially minoritized groups. Pandemic responses should include strategies to address disproportionate risks and inequitable coverage of preventive interventions associated with SDOH.

Clinical index to quantify the 1-year risk for common postpartum mental disorders at the time of delivery (PMH CAREPLAN): development and internal validation.

BACKGROUND: Common postpartum mental health (PMH) disorders such as depression and anxiety are preventable, but determining individual-level risk is difficult. AIMS: To create and internally validate a clinical risk index for common PMH disorders. METHOD: Using population-based health administrative data in Ontario, Canada, comprising sociodemographic, clinical and health service variables easily collectible from hospital birth records, we developed and internally validated a predictive model for common PMH disorders and converted the final model into a risk index. We developed the model in 75% of the cohort (n = 152 362), validating it in the remaining 25% (n = 75 772). RESULTS: The 1-year prevalence of common PMH disorders was 6.0%. Independently associated variables (forming the mnemonic PMH CAREPLAN) that made up the risk index were: (P) prenatal care provider; (M) mental health diagnosis history and medications during pregnancy; (H) psychiatric hospital admissions or emergency department visits; (C) conception type and complications; (A) apprehension of newborn by child services (newborn taken into care); (R) region of maternal origin; (E) extremes of gestational age at birth; (P) primary maternal language; (L) lactation intention; (A) maternal age; (N) number of prenatal visits. In the index (scored 0-39), 1-year common PMH disorder risk ranged from 1.5 to 40.5%. Discrimination (C-statistic) was 0.69 in development and validation samples; the 95% confidence interval of expected risk encompassed observed risk for all scores in development and validation samples, indicating adequate risk index calibration. CONCLUSIONS: Individual-level risk of developing a common postpartum mental health disorder can be estimated with data feasibly collectable from birth records. Next steps are external validation and evaluation of various cut-off scores for their utility in guiding postpartum individuals to interventions that reduce their risk of illness.

Intellectual/developmental disabilities among people incarcerated in federal correctional facilities in Ontario, Canada: Examining prevalence, health and correctional characteristics.

BACKGROUND: There is little research with people who experience intellectual/developmental disabilities and imprisonment. METHODS: The study linked health and correctional data to examine prevalence of intellectual/developmental disabilities and health and correctional characteristics among adults experiencing their first federal incarceration between 1 January 2002 and 31 December 2011 (n = 9278) and two non-incarcerated groups (n = 10,086,802). RESULTS: The prevalence of intellectual/developmental disabilities was 2.1% in the incarcerated group and 0.9% in the non-incarcerated group. Before incarceration, those with, versus without, intellectual/developmental disabilities were at greater risk of traumatic brain injury, mental illness, and substance use disorders. While incarcerated, those with intellectual/developmental disabilities were more likely to incur serious institutional disciplinary charges. Post-incarceration, persons with intellectual/developmental disabilities were at greater risk of emergency department visits, and psychiatric and acute hospitalizations, than the non-incarcerated groups. CONCLUSIONS: People with intellectual/developmental disabilities are overrepresented in Canadian federal correctional institutions. The authors offer strategies to support people prior to, during, and post-incarceration.

Individual and social determinants of SARS-CoV-2 testing and positivity in Ontario, Canada: a population-wide study.

BACKGROUND: Optimizing the public health response to reduce the burden of COVID-19 necessitates characterizing population-level heterogeneity of risks for the disease. However, heterogeneity in SARS-CoV-2 testing may introduce biased estimates depending on analytic design. We aimed to explore the potential for collider bias in a large study of disease determinants, and evaluate individual, environmental and social determinants associated with SARS-CoV-2 testing and diagnosis among residents of Ontario, Canada. METHODS: We explored the potential for collider bias and characterized individual, environmental and social determinants of being tested and testing positive for SARS-CoV-2 infection using cross-sectional analyses among 14.7 million community-dwelling people in Ontario, Canada. Among those with a diagnosis, we used separate analytic designs to compare predictors of people testing positive versus negative; symptomatic people testing positive versus testing negative; and people testing positive versus people not testing positive (i.e., testing negative or not being tested). Our analyses included tests conducted between Mar. 1 and June 20, 2020. RESULTS: Of 14 695 579 people, we found that 758 691 were tested for SARS-CoV-2, of whom 25 030 (3.3%) had a positive test result. The further the odds of testing from the null, the more variability we generally observed in the odds of diagnosis across analytic design, particularly among individual factors. We found that there was less variability in testing by social determinants across analytic designs. Residing in areas with the highest household density (adjusted odds ratio [OR] 1.86, 95% confidence interval [CI] 1.75-1.98), highest proportion of essential workers (adjusted OR 1.58, 95% CI 1.48-1.69), lowest educational attainment (adjusted OR 1.33, 95% CI 1.26-1.41) and highest proportion of recent immigrants (adjusted OR 1.10, 95% CI 1.05-1.15) were consistently related to increased odds of SARS-CoV-2 diagnosis regardless of analytic design. INTERPRETATION: Where testing is limited, our results suggest that risk factors may be better estimated using population comparators rather than test-negative comparators. Optimizing COVID-19 responses necessitates investment in and sufficient coverage of structural interventions tailored to heterogeneity in social determinants of risk, including household crowding, occupation and structural racism.

Prevalence of Prescribed Opioid Claims Among Persons With Traumatic Spinal Cord Injury in Ontario, Canada: A Population-Based Retrospective Cohort Study.

OBJECTIVES: To examine prescription opioid claims among individuals with traumatic spinal cord injury (SCI) and to identify factors associated with both chronic opioid and chronic high-dose opioid use. DESIGN: Retrospective cohort study using population-level administrative data. SETTING: Ontario, Canada. PARTICIPANTS: Individuals (N=1842) with traumatic SCI between April 1, 2004 and March 31, 2015. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Proportion of cohort with chronic opioid use (≥90d supply) and proportion with chronic high-dose opioid use (≥90d supply exceeding 90 mg morphine equivalent) between April 1, 2016 and March 31, 2017 (observation period). RESULTS: A total of 1842 individuals with traumatic SCI were identified (74% men), with a median age of 51 years (interquartile range [IQR], 34-64y) and median duration of injury of 6 years (IQR, 4-9y). During the observation period, 35% were dispensed at least 1 opioid and 19.8% received chronic opioids, 39% of whom received more than 90 mg daily (chronic high dose). The median daily morphine equivalent dose was 212 mg morphine equivalent (IQR, 135.5-345.3 mg) for chronic high-dose users. Significant risk factors for chronic opioid use were male sex; age between 40 and 60 years; lower income; multimorbidity; thoracic, lumbar, or sacral level of injury; and having a previous diagnosis of osteoarthritis. Risk factors for chronic high-dose opioid use were an extended time since injury, age between 40 and 50 years, and increasing comorbidity. CONCLUSIONS: A large proportion of individuals with traumatic SCI were dispensed an opioid in a recent 1-year period. A substantial proportion were dispensed more than 90 mg of morphine equivalents, which is the maximum recommended by the Canadian opioid guideline. Further research is needed to understand the risk factors associated with chronic, high-dose opioid use in this population.

Prevalence of prescribed opioid claims among persons with nontraumatic spinal cord dysfunction in Ontario, Canada: a population-based retrospective cohort study.

STUDY DESIGN: Cohort study. OBJECTIVE: To determine the prevalence and to identify predictors of prescription opioid use among persons with nontraumatic spinal cord dysfunction within 1 year after discharge from inpatient rehabilitation. SETTING: Ontario, Canada. METHODS: We conducted a retrospective cohort study using administrative data to determine predictors of receiving prescription opioids during the 1 year after discharge from inpatient rehabilitation among persons with nontraumatic spinal cord dysfunction between April 1, 2004 and March 31, 2015. We modeled the outcome using a Poisson multivariable regression and reported relative risks with 95% confidence intervals. RESULTS: We identified 3468 individuals with nontraumatic spinal cord dysfunction (50% male) with 67% who were aged ≥66. Over half of the cohort (60%) received opioids during the observation period. Older adults (≥66 years old) were significantly more likely to experience comorbidities (p < 0.05) but less likely to be dispensed opioids following rehabilitation discharge. Being female, previous opioid use before rehabilitation, experiencing lower continuity of care, increasing comorbidity level, low functional status, and having a previous diagnosis of osteoarthritis or mental illness were significant risk factors for receiving opioids after discharge, as shown in a multivariable analysis. Increasing length of rehabilitation stay and higher income were protective against opioid receipt after discharge. CONCLUSION: Many individuals with nontraumatic spinal cord dysfunction in Ontario are prescribed opioids after discharge from inpatient rehabilitation. This may be problematic due to the number of severe complications that may arise from opioid use and their use in this population warrants future research.

Prescription medications dispensed following a nontraumatic spinal cord dysfunction: a retrospective population-based study in Ontario, Canada.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To examine the prevalence of polypharmacy for individuals with nontraumatic spinal cord dysfunction (NTSCD) following inpatient rehabilitation and to determine associated risk factors. SETTING: Ontario, Canada. METHODS: Administrative data housed at ICES, Toronto, Ontario were used. Between 2004 and 2015, we investigated prescription medications dispensed over a 1-year period for persons following an NTSCD-related inpatient rehabilitation admission. Descriptive and analytical statistics were conducted. Using a robust Poisson multivariable regression model, relative risks related to polypharmacy (ten or more drug classes) were calculated. Main independent variables were sex, age, income quintile, and continuity of care with outpatient physician visits. RESULTS: We identified 3468 persons with NTSCD during the observation window. The mean number of drug classes taken post-inpatient rehabilitation was 11.7 (SD = 6.0), with 4.0 different prescribers (SD = 2.5) and 1.8 unique pharmacies (SD = 1.0). Significant predictors for post-discharge polypharmacy were: being female, lower income, higher comorbidities prior to admission, lower Functional Independence Measure at discharge, previous number of medication classes dispensed in year prior to admission, and lower continuity of care with outpatient physician visits. The most common drugs dispensed post-inpatient rehabilitation were antihypertensives (70.0%), laxatives (61.6%), opioids (59.5%), and antibiotics (57.8%). CONCLUSION: Similar to previous research with traumatic spinal cord injury, our results indicate that polypharmacy is prevalent among persons with NTSCD. Additional research examining medication therapy management for NTSCD is suggested.

The prevalence and health status of people with developmental disabilities in provincial prisons in Ontario, Canada: A retrospective cohort study.

BACKGROUND: Data on the prevalence of developmental disabilities in people who experience imprisonment and on their characteristics are lacking. METHODS: The present authors identified adults with developmental disabilities who were released from Ontario provincial prisons in 2010 and a general population comparator group using administrative data. The present authors examined demographic characteristics, morbidity and healthcare use. RESULTS: The prevalence of developmental disabilities was 2.2% in the prison group (N = 52,302) and 0.7% in the general population (N = 10,466,847). The prevalence of psychotic illness, substance-related disorder and self-harm was higher among people in the prison group with developmental disabilities. People with developmental disabilities were more likely to have emergency department visits and hospitalizations in prison and in the year after release. CONCLUSIONS: People with developmental disabilities are overrepresented in provincial prisons and have a high burden of disease. Strategies are indicated to prevent incarceration and to improve health.

Characterising violent deaths of undetermined intent: a population-based study, 1999-2012.

OBJECTIVES: Violent deaths classified as undetermined intent (UD) are sometimes included in suicide counts. This study investigated age and sex differences, along with socioeconomic gradients in UD and suicide deaths in the province of Ontario between 1999 and 2012. METHODS: We used data from the Institute for Clinical Evaluative Sciences, which has linked vital statistics from the Office of the Registrar General Deaths register with Census data between 1999 and 2012. Socioeconomic status was operationalised through the four dimensions of the Ontario Marginalization Index. We computed age-specific and annual age-standardised mortality rates, and risk ratios to calculate risk gradients according to each of the four dimensions of marginalization. RESULTS: Rates of UD-classified deaths were highest for men aged 45-64 years residing in the most materially deprived (7.9 per 100 000 population (95% CI 6.8 to 9.0)) and residentially unstable (8.1 (95% CI 7.1 to 9.1)) neighbourhoods. Similarly, suicide rates were highest among these same groups of men aged 45-64 living in the most materially deprived (28.2 (95% CI 26.1 to 30.3)) and residentially unstable (30.7 (95% CI 28.7 to 32.6)) neighbourhoods. Relative to methods of death, poisoning was the most frequently used method in UD cases (64%), while it represented the second most common method (27%) among suicides after hanging (40%). DISCUSSION: The similarities observed between both causes of death suggest that at least a proportion of UD deaths may be misclassified suicide cases. However, the discrepancies identified in this analysis seem to indicate that not all UD deaths are misclassified suicides.

Can high-cost spending in the community signal admission to hospital? A dynamic modeling study for urgent and elective cardiovascular patients.

BACKGROUND: Much of the research on high-cost patients in healthcare has taken a static approach to studying what is actually a dynamic process. High-cost patients often utilize services across multiple sectors along care pathways, but due to the cross-sectional nature of many study designs, we lack a clear understanding of the temporal relationship between high-cost spending in community and acute care. Studying care trajectories for high cost patients with cardiovascular disease (CVD) can shed light on the dynamic interplay between community-based and acute care along the care continuum, and provide information about signals in community care that may indicate future elective and urgent hospitalizations. METHODS: Using linked health administrative data in Ontario, Canada, 74,683 incident cases with cardiovascular disease were identified between the years 2009 and 2011. Patients were followed for 36 months (total study duration 2009-2014) until the first urgent or elective admission to hospital for a heart-related condition. We used an extended Cox survival model with competing risks to study the relationship between high-cost spending in community care with two mutually exclusive outcomes: urgent or elective hospitalizations. RESULTS: Elective hospitalizations were most clearly signaled by a high-cost utilization of community-based specialist services in the month prior to hospital admission (hazard ratio 9.074, p < 0.0001), while urgent hospitalizations were signaled by high cost usage across all community-based sectors of care (from general practitioner & specialist visits, home care, laboratory services and emergency department (ED) usage). Urgent hospitalizations were most clearly signaled by high cost usage in ED in the month prior to hospital admission (hazard ratio 2.563, p < 0.0001). CONCLUSION: By studying the dynamic nature of patient care trajectories, we may use community-based spending patterns as signals in the system that can point to future and elective hospitalizations for CVD. These community-based spending signals may be useful for identifying opportunities for intervention along the care trajectory, particularly for urgent CVD patients for whom future hospitalizations are difficult to anticipate.

Prescription drug claims following a traumatic spinal cord injury for older adults: a retrospective population-based study in Ontario, Canada.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The objectives for this study were to examine the prevalence of polypharmacy for people with traumatic spinal cord injury (SCI) following injury and to determine risk factors. SETTING: Ontario, Canada METHODS: We used provincial-level administrative health services data of publicly funded healthcare encounters housed at the Institute for Clinical Evaluative Sciences, Toronto, Ontario. We examined prescription medications dispensed over a 1 year period post injury for persons 66+ years with an index traumatic SCI between 2004 and 2014. Polypharmacy was defined as being on 10 or more drug classes. Descriptive and analytical statistics were conducted. Relative risks and 95% confidence limits for factors related to polypharmacy were calculated using a robust Poisson multivariate regression model. RESULTS: We identified 418 cases of persons with traumatic SCI during the observation window. A total of 233 patients (56%) were taking at least 10 drug classes in the year following discharge from care for traumatic SCI. The mean number of drug classes taken post injury was 11 (SD = 6). Continuity of care was significantly associated with polypharmacy, with a higher continuity of care (having at least 75% of visits with the same doctor) reducing the risk of polypharmacy. The most common drugs prescribed were laxatives, opioids and cardiovascular-related drugs. CONCLUSION: Findings suggest that polypharmacy is extensive among older adults with traumatic SCI. Persons with better continuity of care are less likely to have polypharmacy compared to those with less continuity. SPONSORSHIP: This project was funded by a Connaught New Investigator Award (University of Toronto), and the Craig H. Neilsen Foundation Psychosocial Research Pilot Grant (Grant #441259).

Validation of Algorithms to Identify Invasive Electrophysiology Procedures Using Administrative Data in Ontario, Canada.

BACKGROUND: Administrative database research can provide insight into the real-world effectiveness of invasive electrophysiology procedures. However, no validated algorithm to identify these procedures within administrative data currently exists. OBJECTIVE: To develop and validate algorithms to identify atrial fibrillation (AF), atrial flutter (AFL), supraventricular tachycardia (SVT) catheter ablation procedures, and diagnostic electrophysiology studies (EPS) within administrative data. METHODS: Algorithms consisting of physician procedural billing codes and their associated most responsible hospital diagnosis codes were used to identify potential AF, AFL, SVT catheter ablation procedures and diagnostic EPS within large administrative databases in Ontario, Canada. The potential procedures were then limited to those performed between October 1, 2011 and March 31, 2013 at a single large regional cardiac center (Sunnybrook Health Sciences Center) in Ontario, Canada. These procedures were compared with a gold-standard cohort of patients known to have undergone invasive electrophysiology procedures during the same time period at the same institution. The sensitivity, specificity, positive and negative predictive values of each algorithm was determined. RESULTS: Algorithms specific to each of AF, AFL, and SVT ablation were associated with a moderate sensitivity (75%-86%), high specificity (95%-98%), positive (95%-98%), and negative (99%) predictive values. The best algorithm to identify diagnostic EPS was less optimal with a sensitivity of 61% and positive predictive value of 88%. CONCLUSIONS: Algorithms using a combination of physician procedural billing codes and accompanying most responsible hospital diagnosis may identify catheter ablation procedures within administrative data with a high degree of accuracy. Diagnostic EPS may be identified with reduced accuracy.

A population-based study of homicide deaths in Ontario, Canada using linked death records.

BACKGROUND: Homicide - a lethal expression of violence - has garnered little attention from public health researchers and health policy makers, despite the fact that homicides are a cause of preventable and premature death. Identifying populations at risk and the upstream determinants of homicide are important for addressing inequalities that hinder population health. This population-based study investigates the public health significance of homicides in Ontario, Canada, over the period of 1999-2012. We quantified the relative burden of homicides by comparing the socioeconomic gradient in homicides with the leading causes of death, cardiovascular disease (CVD) and neoplasm, and estimated the potential years of life lost (PYLL) due to homicide. METHODS: We linked vital statistics from the Office of the Registrar General Deaths register (ORG-D) with Census and administrative data for all Ontario residents. We extracted all homicide, neoplasm, and cardiovascular deaths from 1999 to 2012, using International Classification of Diseases codes. For socioeconomic status (SES), we used two dimensions of the Ontario Marginalization Index (ON-Marg): material deprivation and residential instability. Trends were summarized across deprivation indices using age-specific rates, rate ratios, and PYLL. RESULTS: Young males, 15-29 years old, were the main victims of homicide with a rate of 3.85 [IC 95%: 3.56; 4.13] per 100,000 population and experienced an upward trend over the study period. The socioeconomic neighbourhood gradient was substantial and higher than the gradient for both cardiovascular and neoplasms. Finally, the PYLL due to homicide were 63,512 and 24,066 years for males and females, respectively. CONCLUSIONS: Homicides are an important cause of death among young males, and populations living in disadvantaged neighbourhoods. Our findings raise concerns about the burden of homicides in the Canadian population and the importance of addressing social determinants to address these premature deaths.

Déterminants individuels et sociaux du test de dépistage du SRAS-CoV-2 et de l'obtention d'un résultat positif en Ontario, au Canada: une étude populationnelle.

CONTEXTE: Optimiser la réponse de la santé publique pour diminuer le fardeau de la COVID-19 nécessite la caractérisation de l'hétérogénéité du risque posé par la maladie à l'échelle de la population. Cependant, l'hétérogénéité du dépistage du SRAS-CoV-2 peut fausser les estimations selon le modèle d'étude analytique utilisé. Notre objectif était d'explorer les biais collisionneurs dans le cadre d'une vaste étude portant sur les déterminants de la maladie et d'évaluer les déterminants individuels, environnementaux et sociaux du dépistage et du diagnostic du SRAS-CoV-2 parmi les résidents de l'Ontario, au Canada. MÉTHODES: Nous avons exploré la présence potentielle de biais collisionneurs et caractérisé les déterminants individuels, environnementaux et sociaux de l'obtention d'un test de dépistage et d'un résultat positif à la présence de l'infection au SRAS-CoV-2 à l'aide d'analyses transversales parmi les 14,7 millions de personnes vivant dans la collectivité en Ontario, au Canada. Parmi les personnes ayant obtenu un diagnostic, nous avons utilisé des études analytiques distinctes afin de comparer les prédicteurs pour les personnes d'obtenir un résultat de test de dépistage positif plutôt que négatif, pour les personnes symptomatiques d'obtenir un résultat de test de dépistage positif plutôt que négatif et pour les personnes d'obtenir un résultat de test de dépistage positif plutôt que de ne pas obtenir un résultat positif (c.-à-d., obtenir un résultat de test de dépistage négatif ou ne pas obtenir de test de dépistage). Nos analyses comprennent des tests de dépistage réalisés entre le 1er mars et le 20 juin 2020. RÉSULTATS: Sur 14 695 579 personnes, nous avons constaté que 758 691 d'entre elles ont passé un test de dépistage du SRAS-CoV-2, parmi lesquelles 25 030 (3,3 %) ont obtenu un résultat positif. Plus la probabilité d'obtenir un test de dépistage s'éloignait de zéro, plus la variabilité généralement observée dans la probabilité d'un diagnostic était grande parmi les modèles d'études analytiques, particulièrement en ce qui a trait aux facteurs individuels. Nous avons constaté que la variabilité dans l'obtention d'un test de dépistage était moins importante en fonction des déterminants sociaux dans l'ensemble des études analytiques. Les facteurs tels que le fait d'habiter dans une région ayant une plus haute densité des ménages (rapport de cotes corrigé 1,86; intervalle de confiance [IC] à 95 % 1,75­1,98), une plus grande proportion de travailleurs essentiels (rapport de cotes corrigé 1,58; IC à 95 % 1,48­1,69), une population atteignant un plus faible niveau de scolarité (rapport de cotes corrigé 1,33; IC à 95 % 1,26­1,41) et une plus grande proportion d'immigrants récents (rapport de cotes corrigé 1,10; IC à 95 % 1,05­1,15), étaient systématiquement corrélés à une probabilité plus importante d'obtenir un diagnostic de SRAS-CoV-2, peu importe le modèle d'étude analytique employé. INTERPRÉTATION: Lorsque la capacité de dépister est limitée, nos résultats suggèrent que les facteurs de risque peuvent être estimés plus adéquatement en utilisant des comparateurs populationnels plutôt que des comparateurs de résultat négatif au test de dépistage. Optimiser la lutte contre la COVID-19 nécessite des investissements dans des interventions structurelles déployées de façon suffisante et adaptées à l'hétérogénéité des déterminants sociaux du risque, dont le surpeuplement des ménages, l'occupation professionnelle et le racisme structurel.

Rehospitalization After Traumatic Brain Injury: A Population-Based Study.

OBJECTIVE: To examine, from a Canadian population-based perspective, the incidence and etiology of long-term hospital utilization among persons living with traumatic brain injury (TBI) by age and sex. DESIGN: Retrospective cohort study. SETTING: Acute care hospitals. PARTICIPANTS: Index cases of TBI (N=29,269) were identified from the Discharge Abstract Database for fiscal years 2002/2003 through 2009/2010 and were followed-up until 36 months after injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rehospitalization was defined as admission to an acute care facility that occurred up to 36 months after index injury. Diagnoses associated with subsequent rehospitalization were examined by age and sex. RESULTS: Of the patients with TBI, 35.5% (n=10,390) were subsequently hospitalized during the 3-year follow-up period. Multivariable logistic regression (controlling for index admission hospital) identified men, older age, mechanism of injury being a fall, greater injury severity, rural residence, greater comorbidity, and psychiatric comorbidity to be significant predictors of rehospitalization in a 3-year period postinjury. The most common causes for rehospitalization differed by age and sex. CONCLUSIONS: Rehospitalization after TBI is common. Factors associated with rehospitalization can inform long-term postdischarge planning. Findings also support examining causes for rehospitalization by age and sex.

The association between multimorbidity and hospitalization is modified by individual demographics and physician continuity of care: a retrospective cohort study.

BACKGROUND: Multimorbidity poses a significant clinical challenge and has been linked to greater health services use, including hospitalization; however, we have little knowledge about the influence of contextual factors on outcomes in this population. OBJECTIVES: To describe the extent to which the association between multimorbidity and hospitalization is modified by age, gender, primary care practice model, or continuity of care (COC) among adults with at least one chronic condition. METHODS: A retrospective cohort study with linked population-based administrative data. SETTING: Ontario, Canada. COHORT: All individuals 18 and older with at least one of 16 priority chronic conditions as of April 1, 2009 (baseline). MAIN OUTCOME MEASURES: Any hospitalization, 3 or more hospitalizations, non-medical discharge delay, and 30-day readmission within the 1 year following baseline. RESULTS: Of 5,958,514 individuals, 484,872 (8.1 %) experienced 646,347 hospitalizations. There was a monotonic increase in the likelihood of hospitalization and related outcomes with increasing multimorbidity which was modified by age, gender, and COC but not primary care practice model. The effect of increasing multimorbidity was greater in younger adults than older adults and in those with lower COC than with higher COC. The effect of increasing multimorbidity on hospitalization was greater in men than women but reversed for the other outcomes. CONCLUSIONS: The effect of multimorbidity on hospitalization is influenced by age and gender, important considerations in the development of person-centred care models. Greater continuity of physician care lessened the effect of multimorbidity on hospitalization, further demonstrating the need for care continuity across providers for people with chronic conditions.

The increasing burden and complexity of multimorbidity.

BACKGROUND: Multimorbidity, the co-occurrence of two or more chronic conditions, is common among older adults and is known to be associated with high costs and gaps in quality of care. Population-based estimates of multimorbidity are not readily available, which makes future planning a challenge. We aimed to estimate the population-based prevalence and trends of multimorbidity in Ontario, Canada and to examine patterns in the co-occurrence of chronic conditions. METHODS: This retrospective cohort study includes all Ontarians (aged 0 to 105 years) with at least one of 16 common chronic conditions. Descriptive statistics were used to examine and compare the prevalence of multimorbidity by age and number of conditions in 2003 and 2009. The co-occurrence of chronic conditions among individuals with multimorbidity was also explored. RESULTS: The prevalence of multimorbidity among Ontarians rose from 17.4% in 2003 to 24.3% in 2009, a 40% increase. This increase over time was evident across all age groups. Within individual chronic conditions, multimorbidity rates ranged from 44% to 99%. Remarkably, there were no dominant patterns of co-occurring conditions. CONCLUSION: The high prevalence of multimorbidity and numerous combinations of conditions suggests that single, disease-oriented management programs may be less effective or efficient tools for high quality care compared to person-centered approaches.