COVID-19 and its Cardiac and Neurological Complications among Ontario Visible Minorities.

BACKGROUND: Due to lack of data on the epidemiology, cardiac, and neurological complications among Ontario visible minorities (Chinese and South Asians) affected by coronavirus disease (COVID-19), this population-based retrospective study was undertaken to study them systematically. METHODS: From January 1, 2020 to September 30, 2020 using the last name algorithm to identify Ontario Chinese and South Asians who were tested positive by PCR for COVID-19, their demographics, cardiac, and neurological complications including hospitalization and emergency visit rates were analyzed compared to the general population. RESULTS: Chinese (N = 1,186) with COVID-19 were found to be older (mean age 50.7 years) compared to the general population (N = 42,547) (mean age 47.6 years) (p < 0.001), while South Asians (N = 3,459) were younger (age of 42.1 years) (p < 0.001). The 30-day crude rate for cardiac complications among Chinese was 169/10,000 (p = 0.069), while for South Asians, it was 64/10,000 (p = 0.008) and, for the general population, it was 112/10,000. For neurological complications, the 30-day crude rate for Chinese was 160/10,000 (p < 0.001); South Asians was 40/10,000 (p = 0.526), and general population was 48/10,000. The 30-day all-cause mortality rate was significantly higher for Chinese at 8.1% vs 5.0% for the general population (p < 0.001), while it was lower in South Asians at 2.1% (p < 0.001). CONCLUSIONS: Chinese and South Asians in Ontario affected by COVID-19 during the first wave of the pandemic were found to have a significant difference in their demographics, cardiac, and neurological outcomes.

Troponin testing after noncardiac surgery: a population-based historical cohort study on variation and factors associated with testing in Ontario.

BACKGROUND: International practice guidelines make different recommendations for postoperative troponin testing to detect perioperative myocardial infarction and myocardial injury after noncardiac surgery. To gain insights into current testing patterns, we evaluated predictors of routine troponin testing after three commonly performed major noncardiac surgeries. METHODS: We conducted a population-based historical cohort study of adults having major orthopedic, colorectal, or vascular surgery in Ontario, Canada from 1 January 2010 to 31 December 2017. We used hierarchical logistic regression modelling to assess the association of patient, surgery, and hospital factors with postoperative troponin testing, while accounting for clustering at the hospital level. We characterized hospital-level variation by the intraclass correlation coefficient (ICC), which was adjusted for various characteristics. RESULTS: The cohort included 176,454 eligible patients. Hospital-specific adjusted testing rates ranged from 0-20.1% for orthopedic surgery, 0-43.8% for colorectal surgery, and 19.6-88.0% for vascular surgery. Older age, urgent surgery status, and surgery duration were consistently associated with higher rates of testing for all three surgeries. Higher Revised Cardiac Risk Index scores were associated with higher odds of testing for orthopedic and colorectal surgery, but not for vascular surgery. Even after adjustment, the ICCs were 9.2%, 7.4%, and 24.1% for orthopedic, general, and vascular surgery, respectively. CONCLUSIONS: Troponin testing varied substantially across hospitals for selected major noncardiac surgery procedures even after accounting for differences in patient-level cardiac risk factors. Our observations lend support to a more standardized approach for troponin testing after noncardiac surgery.

RéSUMé: CONTEXTE: Les directives de pratique internationales émettent différentes recommandations en ce qui concerne les dosages postopératoires de troponines afin de détecter l'infarctus du myocarde et les lésions myocardiques périopératoires après une chirurgie non cardiaque. Pour mieux comprendre les habitudes de test actuelles, nous avons évalué les prédicteurs de dosage de troponines de routine après trois chirurgies non cardiaques majeures couramment réalisées. MéTHODE: Nous avons réalisé une étude de cohorte historique basée sur la population d'adultes bénéficiant d'une chirurgie orthopédique, colorectale ou vasculaire majeure en Ontario, au Canada, entre le 1er janvier 2010 et le 31 décembre 2017. Nous avons utilisé un modèle de régression logistique hiérarchique afin d'évaluer l'association des facteurs liés au patient, à la chirurgie et à l'hôpital avec les dosages de troponines postopératoires, tout en tenant compte des groupements au niveau hospitalier. Nous avons caractérisé la variation hospitalière par le coefficient de corrélation intraclasse (CCI), qui a été ajusté pour tenir compte de diverses caractéristiques. RéSULTATS: La cohorte comprenait 176 454 patients éligibles. Les taux de tests ajustés propres à l'hôpital variaient de 0 à 20,1 % pour les chirurgies orthopédiques, de 0 à 43,8 % pour les chirurgies colorectales et de 19,6 à 88,0 % pour les chirurgies vasculaires. Un âge plus avancé, un statut de chirurgie urgente et la durée de la chirurgie étaient systématiquement associés à des taux plus élevés de dosages pour les trois chirurgies. Des scores plus élevés sur l'Indice de risque cardiaque révisé étaient associés à des probabilités plus élevées de dosages pour les chirurgies orthopédiques et colorectales, mais pas pour les chirurgies vasculaires. Même après ajustement, les CCI étaient de 9,2 %, 7,4 % et 24,1 % pour les chirurgies orthopédiques, générales et vasculaires, respectivement. CONCLUSION: Les dosages de troponines varient considérablement d'un hôpital à l'autre pour certaines interventions chirurgicales non cardiaques majeures, même après avoir pris en compte les différences dans les facteurs de risque cardiaques liés au patient. Nos observations appuient une approche plus standardisée des dosages de troponines après une chirurgie non cardiaque.

Real-world risk of cardiovascular outcomes associated with hypertriglyceridaemia among individuals with atherosclerotic cardiovascular disease and potential eligibility for emerging therapies.

AIMS: Hypertriglyceridaemia in patients with atherosclerotic cardiovascular disease (ASCVD) has been in focus following the REDUCE-IT trial showing benefit with icosapent ethyl. Among individuals with prevalent ASCVD, we sought to quantify the contemporary, real-world risk of ASCVD events associated with hypertriglyceridaemia, as well as estimate icosapent ethyl eligibility and compare trial participants with REDUCE-IT-like individuals in the population. METHODS AND RESULTS: We examined data from 2 424 865 adults with lipid panels in the Ontario population. Among those with prevalent ASCVD, we examined adjusted associations between triglyceride (TG) and ASCVD events (first occurrence of myocardial infarction, unstable angina, stroke or transient ischaemic attack, coronary revascularization, or cardiovascular death). The proportion of patients with ASCVD potentially eligible for icosapent ethyl was estimated as those with TG 135-499 mg/dL (1.52-5.63 mmol/L) and low-density lipoprotein cholesterol (LDLc) 41-100 mg/dL (1.06-2.59 mmol/L), similar to the lipid cut-offs in REDUCE-IT, and their demographics and event rates examined. Among 196 717 individuals with ASCVD, median age was 69 years and 30% were female. A total of 24 097 composite ASCVD events occurred over a mean (standard deviation) 2.9 (0.5) years of follow-up. Increasing TG was associated with a graded, progressively higher hazard of ASCVD events. Twenty-five percent (49 886) of individuals with ASCVD had hypertriglyceridaemia and controlled LDLc; these patients were demographically similar to those in REDUCE-IT with comparable event rates. CONCLUSIONS: Among patients with ASCVD, hypertriglyceridaemia is common, and is associated with higher ASCVD risk across a range of TG. It is possible that as many as one in four patients with ASCVD may be candidates for emerging therapies.

Clinical outcomes for chest pain patients discharged home from emergency departments using high-sensitivity versus conventional cardiac troponin assays.

BACKGROUND: High-sensitivity cardiac troponin (hs-cTn) assays enhance detection of lower circulating troponin concentrations, but the impact on outcomes in clinical practice is unclear. Our objective was to compare outcomes of chest pain patients discharged from emergency departments (EDs) using hs-cTn and conventional troponin (cTn) assays. METHODS: We conducted an observational study of chest pain patients aged 40-105 years who presented to an ED from April 1, 2013, to March 31, 2017, and were discharged home. We compared 30-day and 1-year outcomes of EDs that used hs-cTn versus cTn assays. The primary outcome was a composite of all-cause death, myocardial infarction or unstable angina. Comparisons were conducted with (1) no adjustment; (2) adjustment for demographic, socioeconomic, and hospital characteristics; and (3) full clinical adjustment. RESULTS: Among the 394,910 patients, 62,138 (15.7%) were evaluated at hs-cTn EDs and 332,772 (84.3%) were evaluated at cTn EDs. Patients discharged from hs-cTn EDs were less likely to have diabetes, hypertension, or prior heart disease. At 30 days, the unadjusted primary outcome rate was lower in hs-cTn EDs (0.9% vs 1.0%, P < .001). The 30-day hazard ratios for the primary outcome were 0.84 (95% CI 0.77-0.92) for no adjustment and 0.98 (95% CI 0.88-1.08) for full adjustment. Over 1 year, patients discharged from hs-cTn EDs had significantly fewer primary outcomes (3.7% vs 4.1%, P < .001) and lower hazard ratio (0.93; 95% CI 0.89-0.98) even after full adjustment. CONCLUSIONS: Hs-cTn testing was associated with a significantly lower adjusted hazard of myocardial infarction, angina, and all-cause hospitalization at 1 year but not 30 days.

Calibration and discrimination of the Framingham Risk Score and the Pooled Cohort Equations.

BACKGROUND: Although accurate risk prediction is essential in guiding treatment decisions in primary prevention of atherosclerotic cardiovascular disease, the accuracy of the Framingham Risk Score (recommended by a Canadian guideline) and the Pooled Cohort Equations (recommended by US guidelines) has not been assessed in a large contemporary Canadian population. Our primary objective was to assess the calibration and discrimination of the Framingham Risk Score and Pooled Cohort Equations in Ontario, Canada. METHODS: We conducted an observational study involving Ontario residents aged 40 to 79 years, without a history of atherosclerotic cardiovascular disease, who underwent cholesterol testing and blood pressure measurement from Jan. 1, 2010, to Dec. 31, 2014. We compared predicted event rates generated by the Framingham Risk Score and the Pooled Cohort Equations with observed event rates at 5 years using linkages from validated administrative databases. RESULTS: Our study cohort included 84 617 individuals (mean age 56.3 yr, 56.9% female). Over a maximum follow-up period of 5 years, we observed 2162 (2.6%) events according to the outcome definition of the Framingham Risk Score, and 1224 (1.4%) events according to the outcome definition of the Pooled Cohort Equations. The predicted event rate of 5.78% by the Framingham Risk Score and 3.51% by the Pooled Cohort Equations at 5 years overestimated observed event rates by 101% and 115%, respectively. The degree of overestimation differed by age and ethnicity. The C statistics for the Framingham Risk Score (0.74) and Pooled Cohort Equations (0.73) were similar. INTERPRETATION: The Framingham Risk Score and Pooled Cohort Equations significantly overpredicted the actual risks of atherosclerotic cardiovascular disease events in a large population from Ontario. Our finding suggests the need for further refinement of cardiovascular disease risk prediction scores to suit the characteristics of a multiethnic Canadian population.

Association Between Adherence to Fractional Flow Reserve Treatment Thresholds and Major Adverse Cardiac Events in Patients With Coronary Artery Disease.

Importance: Fractional flow reserve (FFR) is an invasive measurement used to assess the potential of a coronary stenosis to induce myocardial ischemia and guide decisions for percutaneous coronary intervention (PCI). It is not known whether established FFR thresholds for PCI are adhered to in routine interventional practice and whether adherence to these thresholds is associated with better clinical outcomes. Objective: To assess the adherence to evidence-based FFR thresholds for PCI and its association with clinical outcomes. Design, Setting, and Participants: A retrospective, multicenter, population-based cohort study of adults with coronary artery disease undergoing single-vessel FFR assessment (excluding ST-segment elevation myocardial infarction) from April 1, 2013, to March 31, 2018, in Ontario, Canada, and followed up until March 31, 2019, was conducted. Two separate cohorts were created based on FFR thresholds (≤0.80 as ischemic and >0.80 as nonischemic). Inverse probability of treatment weighting was used to account for treatment selection bias. Exposures: PCI vs no PCI. Main Outcomes and Measures: The primary outcome was major adverse cardiac events (MACE) defined by death, myocardial infarction, unstable angina, or urgent coronary revascularization. Results: There were 9106 patients (mean [SD] age, 65 [10.6] years; 35.3% female) who underwent single-vessel FFR measurement. Among 2693 patients with an ischemic FFR, 75.3% received PCI and 24.7% were treated only with medical therapy. In the ischemic FFR cohort, PCI was associated with a significantly lower rate and hazard of MACE at 5 years compared with no PCI (31.5% vs 39.1%; hazard ratio, 0.77 [95% CI, 0.63-0.94]). Among 6413 patients with a nonischemic FFR, 12.6% received PCI and 87.4% were treated with medical therapy only. PCI was associated with a significantly higher rate and hazard of MACE at 5 years compared with no PCI (33.3% vs 24.4%; HR, 1.37 [95% CI, 1.14-1.65]) in this cohort. Conclusions and Relevance: Among patients with coronary artery disease who underwent single-vessel FFR measurement in routine clinical practice, performing PCI, compared with not performing PCI, was significantly associated with a lower rate of MACE for ischemic lesions and a higher rate of MACE for nonischemic lesions. These findings support the performance of PCI procedures according to evidence-based FFR thresholds.

Trends in the incidence and outcomes of patients with aortic stenosis hospitalization.

BACKGROUND: Although the burden of aortic stenosis (AS) on our health care system is expected to rise, little is known regarding its epidemiology at the population level. Our primary objective was to evaluate trends in AS hospitalization, treatment and outcomes. METHODS: We performed a population-based observational study including 37,970 patients newly hospitalized with AS from 2004 and 2013 in Ontario, Canada. We calculated age- and sex-standardized rate of AS hospitalization through direct standardization. The independent association between year of the hospitalization, and 30-day and 1-year mortality rate was evaluated using logistic regression models to account for temporal changes in patient characteristics. RESULTS: The overall age- and sex-standardized AS hospitalization rate increased slightly from 36 per 100,000 in 2004 to 39 per 100,000 in 2013. A substantial increase was seen in patients ≥85years, where hospitalization rates increased 29% from 400 to 516 per 100,000 from 2004 to 2013 (P<.001). In this study period, 36.2% of patients received aortic valve interventions within 30days of hospitalization. Among treated patients, an improving mortality trend was observed in which the adjusted odds ratio (OR) was significantly lower in 2013 as compared to 2004 (OR 0.55 for 30-day mortality, 0.74 for 1-year morality). In contrast, no significant temporal change in mortality was seen among patients without aortic valve intervention. CONCLUSION: AS hospitalizations in the elderly increased significantly beyond that was expected from population growth. Many AS patients did not receive aortic valve intervention after hospitalization. Mortality among the treated patients improved significantly over time.

Long-term risk of stroke and bleeding post-atrial fibrillation ablation.

BACKGROUND: Catheter ablation (CA) is an established therapy for atrial fibrillation (AF). Studies regarding long-term real-world outcomes post-CA have inconsistently accounted for oral anticoagulation (OAC). OBJECTIVES: To describe patterns of OAC use post-CA and to compare the OAC-adjusted long-term risk of stroke and major bleeding in AF patients with and without CA. METHODS: A population-based cohort of AF patients was constructed in Quebec and Ontario, Canada (1999-2014). Propensity score matching was performed to determine the incidence rates of stroke and major bleeding among those undergoing CA, adjusted for time-dependent OAC use. RESULTS: From the entire cohort, 6391 patients were identified as having undergone CA as compared to 482 977 patients who did not. Of these, 1240 patients with government medical insurance undergoing CA were matched with 2427 patients without CA. Post-CA, 78%, 65%, and 61% remained on an OAC at 1, 2, and 5 years, while 75%, 71%, and 68% of patients not undergoing CA were on OACs at 1, 2, and 5 years. At follow-up, there was no statistically significant difference for stroke (adjusted hazard ratio [HR], 0.88; 95% CI, 0.63 to 1.21) or major bleeding (adjusted HR, 0.88; 95% CI, 0.73 to 1.06). CONCLUSION: No evidence was found that CA significantly decreases the risk of stroke or major bleeding when adjusting for OAC use over time. It may be prudent to continue anticoagulation post-CA based on patient-risk profile until randomized trials demonstrate both reduced stroke rates with CA, and improved safety (balancing stroke and bleeding risk) with OAC discontinuation post-CA.

Clinical outcomes after trans-catheter aortic valve replacement in men and women in Ontario, Canada.

OBJECTIVE: Our objective was to evaluate sex-differences in outcomes after trans-catheter aortic valve replacement (TAVR) in a population-based cohort from Ontario, Canada. BACKGROUND: Prior studies comparing outcomes in men and women after TAVR have yielded divergent results. Some studies have suggested that women have better survival than men while others have not corroborated this finding. METHODS: A retrospective observational cohort study was conducted using chart abstraction data on all TAVR procedures performed between 2007 and 2013 in Ontario, Canada. Patients who had emergency TAVR procedures were excluded. The primary outcome was all-cause mortality at 30-days and 1-year. Secondary outcomes included mortality at last follow-up, cause-specific, and all-cause hospital readmission. Inverse probability of treatment weighting (IPTW) using propensity score was used to adjust for baseline differences between men and women. RESULTS: The final study cohort consisted of 453 women and 546 men with a mean follow-up of 3.5 years. Women were generally older and more frail but had less comorbid conditions. Women had lower unadjusted mean EuroScores (7% ± 5% vs 8% ± 7%; P = 0.008), but underwent significantly more trans-apical procedures (26.5% vs 19.2%; P = 0.006) than men. After IPTW, the groups were well balanced. Although mortality was numerically higher for women at 30-days (7.2% vs 5.4%), this was not statistically significant (P = 0.34). At 1-year, there was no difference in mortality (18.2% vs 19.2%; P = 0.85). There were no significant differences in all-cause readmission. CONCLUSION: In this population-based cohort including all patients undergoing TAVR, mortality or all-cause readmission were not significantly different between men and women. © 2017 Wiley Periodicals, Inc.

Factors associated with out-of-hospital cardiac arrest with pulseless electric activity: A population-based study.

BACKGROUND: Many patients with out-of-hospital cardiac arrest present with pulseless electric activity (PEA) rather than shockable rhythm. Despite improvements in resuscitation care, survival of PEA patients remains dismal. Our main objective was to characterize out-of-hospital cardiac arrest patients by initial presenting rhythm and to evaluate independent determinants of PEA. METHODS: A population-based study was conducted using the Toronto Rescu Epistry database with linkage to administrative data in Ontario, Canada. We included patients older than 20 years who had nontraumatic cardiac arrests from 2005 to 2010. Multivariable logistic regression models were constructed to determine factors predicting the occurrence of PEA vs shockable rhythm vs asystole. RESULTS: Of the 9,882 included patients who received treatment, 24.5% had PEA, 26.3% had shockable rhythm, and 49.2% had asystole. Patients with PEA had a mean age of 72 years, 41.2% were female and had multiple comorbidities, and 53.4% were hospitalized in the past year. As compared with shockable rhythm, PEA patients were older, were more likely to be women, and had more comorbidities. As compared with asystole, PEA patients had similar baseline and clinical characteristics, but were substantially more likely to have an arrest witnessed by emergency medical services (odds ratio 13) or by bystander (odds ratio 3.24). Mortality at 30 days was 95.5%, 77.9%, and 98.9% for patients with PEA, shockable rhythm, asystole, respectively. CONCLUSIONS: Patient characteristics differed substantially in those presenting with PEA and shockable rhythm. In contrast, the main distinguishing factor between PEA and asystole cardiac arrest related mainly to factors at the time of the cardiac arrest.

Association of prior ß-blocker use and the outcomes of patients with out-of-hospital cardiac arrest.

UNLABELLED: ß-Blocker therapy is one of the most commonly prescribed treatments for patients with cardiac conditions. In patients with out-of-hospital cardiac arrest (OHCA), however, recent data suggest that prior treatment with ß-blockers could be harmful by lowering the incidence of a shockable presenting rhythm. The main objective of our study was to determine the association between prior ß-blocker use and mortality in OHCA patients. METHODS: An observational study was conducted using the Toronto Rescu Epistry database that captured consecutive OHCA patients from 2005 to 2010. Patients older than 65 years with nontraumatic cardiac arrest and attempted resuscitation were included. Patients prescribed ß-blockers within 90 days of the arrest were compared with those without such therapy. The primary outcome was all-cause mortality at 30 days. Potential confounders were accounted for by inverse probability of treatment weighting using the propensity score. RESULTS: The median age of 8,266 OHCA patients was 79 years, 41% were women, and 2,911 (35.2%) were prescribed a ß-blocker prior to cardiac arrest. Patients prescribed ß-blockers were more likely to have existing cardiac risk factors and cardiovascular conditions. In the propensity-weighted cohort, there were no differences in the presenting rhythm, with 18.4% of patients in the ß-blocker group having a shockable rhythm vs 17.5% in the no ß-blocker group (standardized difference .023). In addition, 30-day mortality was not significantly different between patients prescribed ß-blockers and no ß-blockers (95.6% vs 95.1%, P = .36). CONCLUSION: ß-Blocker use was not associated with lower rates of shockable rhythms or mortality among older patients with OHCA.

Factors associated with physician follow-up among patients with chest pain discharged from the emergency department.

BACKGROUND: Many patients with chest pain do not receive follow-up from a physician after discharge from the emergency department despite significant survival benefit associated with follow-up care. Our objective was to evaluate factors associated with physician follow-up to understand this gap in practice. METHODS: We conducted an observational study involving patients at high risk who were assessed for chest pain and discharged from an emergency department in Ontario between April 2004 and March 2010. We used multivariable logistic regression to determine the association of clinical and nonclinical characteristics with physician follow-up. RESULTS: We identified 56 767 patients, of whom 25.1% did not receive any follow-up by a physician, 69.0% were seen by their primary care physician, and 17.3% were seen by a cardiologist within 30 days. Patients who had medical comorbidities and cardiac conditions such as myocardial infarction or heart failure were less likely to have follow-up. In contrast, a previous visit to a primary care physician was associated with the highest odds of having physician follow-up (odds ratio [OR] 6.44, 95% confidence interval [CI] 5.91-7.01). Similarly, a previous visit to a cardiologist was strongly associated with follow-up by a cardiologist (OR 3.01, 95% CI 2.85-3.17). Patients evaluated in emergency departments with the highest tertile of chest pain volume were more likely to receive follow-up from any physician (OR 1.52, 95% CI 1.31-1.77) and from a cardiologist (OR 2.04, 95% CI 1.61-2.57). INTERPRETATION: Nonclinical factors are strongly associated with physician follow-up for patients with chest pain after discharge from the emergency department. However, patients with comorbidities and at higher risk for future adverse events are less likely to receive follow-up care.

Protection of prior SARS-CoV-2 infection, COVID-19 boosters, and hybrid immunity against Omicron severe illness: A population-based cohort study of five million residents in Canada.

BACKGROUND: Evidence on protection of different patterns of infection- and vaccine-acquired immunity against Omicron-associated severe illness is useful in planning booster vaccination strategies. We examined protection of prior SARS-CoV-2 infection, a third or a fourth COVID-19 vaccine dose, and hybrid immunity against Omicron-associated severe illness. METHODS AND FINDINGS: This population-based cohort study followed five million individuals with at least one SARS-CoV-2 RT-PCR test before November 21, 2021 until an Omicron-associatedhospitalization or death. We used Cox regression models to estimate risks of Omicron-associated hospitalization and a composite severe outcome (hospitalized and death), among individuals with infection- and/or vaccination-acquired immunity. Individuals who were unvaccinated and had no history of a prior infection severed as the reference group. Both adjusted hazard ratios (HR) and corresponding protection (one minus adjusted HR), with 95% confidence intervals (CIs), were reported. Three doses provided 94% (95%CI 93-95) and 93% (95%CI 91-94) protection against Omicron-associated hospitalization at 2-3 and ≥3 months post-vaccination respectively, similar to the protection conferred by three doses and a prior infection (2-3 months: 99%, 95%CI 97-100; ≥3 months: 97%, 95%CI 92-99) and four doses (1 month: 87%, 95%CI 79-92; 1-2 months: 96%, 95%CI 92-98). In individuals ≥65 years old, protection of four doses increased to 95% (95%CI 91-98) at 1-2 months, significantly higher than that of three doses over the follow-up period. Similar results were observed with the composite severe outcome. CONCLUSION: At least three antigenic exposures, achieved by vaccination or infection, confers significant protection against Omicron-associated hospitalization and death in all age groups. Our findings support a third dose for the overall population, regardless of prior infection status, and a fourth dose for the elderly to maintain high level of immunity and substantially reduce risk of severe illness at individual level.

Outcomes of COVID-19 Infection and Vaccination Among Individuals With Myasthenia Gravis.

Importance: There are limited data regarding COVID-19 outcomes and vaccine uptake and safety among people with myasthenia gravis (MG). Objective: To investigate COVID-19-related outcomes and vaccine uptake among a population-based sample of adults with MG. Design, Setting, and Participants: This population-based, matched cohort study in Ontario, Canada, used administrative health data from January 15, 2020, and August 31, 2021. Adults with MG were identified using a validated algorithm. Each patient was matched by age, sex, and geographic area of residence to 5 controls from the general population and from a cohort of individuals with rheumatoid arthritis (RA). Exposure: Patients with MG and matched controls. Main Outcomes and Measures: Main outcomes were COVID-19 infection and related hospitalizations, intensive care unit admissions, and 30-day mortality among patients with MG vs controls. Secondary outcomes were uptake of COVID-19 vaccination among patients with MG vs controls. Results: Among 11 365 233 eligible Ontario residents, 4411 patients with MG (mean [SD] age, 67.7 [15.6] years; 2274 women [51.6%]) were matched to 22 055 general population controls (mean [SD] age, 67.7 [15.6] years; 11 370 women [51.6%]) and 22 055 controls with RA (mean [SD] age, 67.7 [15.6] years; 11 370 women [51.6%]). In the matched cohort, 38 861 of 44 110 individuals (88.1%) were urban residents; in the MG cohort, 3901 (88.4%) were urban residents. Between January 15, 2020, and May 17, 2021, 164 patients with MG (3.7%), 669 general population controls (3.0%), and 668 controls with RA (3.0%) contracted COVID-19. Compared with general population controls and controls with RA, patients with MG had higher rates of COVID-19-associated emergency department visits (36.6% [60 of 164] vs 24.4% [163 of 669] vs 29.9% [200 of 668]), hospital admissions (30.5% [50 of 164] vs 15.1% [101 of 669] vs 20.7% [138 of 668]), and 30-day mortality (14.6% [24 of 164] vs 8.5% [57 of 669] vs 9.9% [66 of 668]). By August 2021, 3540 patients with MG (80.3%) vs 17 913 general population controls (81.2%) had received 2 COVID-19 vaccine doses, and 137 (3.1%) vs 628 (2.8%), respectively had received 1 dose. Of 3461 first vaccine doses for patients with MG, fewer than 6 individuals were hospitalized for MG worsening within 30 days of vaccination. Vaccinated patients with MG had a lower risk than unvaccinated patients with MG of contracting COVID-19 (hazard ratio, 0.43; 95% CI, 0.30-0.60). Conclusions and Relevance: This study suggests that adults with MG who contracted COVID-19 had a higher risk of hospitalization and death compared with matched controls. Vaccine uptake was high, with negligible risk of severe MG exacerbations after vaccination, as well as evidence of effectiveness. The findings support public health policies prioritizing people with MG for vaccination and new COVID-19 therapeutics.

Income and economic exclusion: do they measure the same concept?

INTRODUCTION: In this paper, we create an index of economic exclusion based on validated questionnaires of economic hardship and material deprivation, and examine its association with health in Canada. The main study objective is to determine the extent to which income and this index of economic exclusion index are overlapping measurements of the same concept. METHODS: We used the Canadian Household Panel Survey Pilot and performed multilevel analysis using a sample of 1588 individuals aged 25 to 64, nested within 975 households. RESULTS: While economic exclusion is inversely correlated with both individual and household income, these are not perfectly overlapping constructs. Indeed, not only these indicators weakly correlated, but they also point to slightly different sociodemographic groups at risk of low income and economic exclusion. Furthermore, the respective associations with health are of comparable magnitude, but when these income and economic exclusion indicators are included together in the same model, they point to independent and cumulative, not redundant effects. CONCLUSIONS: We explicitly distinguish, both conceptually and empirically, between income and economic exclusion, one of the main dimensions of social exclusion. Our results suggest that the economic exclusion index we use measures additional aspects of material deprivation that are not captured by income, such as the effective hardship or level of economic 'well-being'.

Epidemiology of COVID-19 and Its Cardiac and Neurologic Complications Among Chinese and South Asians in Ontario: Waves 1, 2, and 3.

Background: Although we had previously reported the cardiac and neurologic outcomes of Chinese and South Asian Ontarians in wave 1 of COVID-19, data on subsequent waves of COVID-19 remain unexamined. This is an extension study of this cohort in waves 2 and 3. Methods: We identified adult Ontarians with a positive COVID-19 polymerase chain reaction test from January 1, 2020 to June 30, 2021, and they were classified as being Chinese or South Asian using a validated surname algorithm; we compared their outcomes of mortality, and cardiac and neurologic complications with those of the general population using multivariable logistic regression models. Results: Compared to the general population (n = 439,977), the Chinese population (n = 15,208) was older (mean age 44.2 vs 40.6 years, P < 0.001) and the South Asian population (n = 46,333) was younger (39.2 years, P < 0.001). The Chinese population had a higher 30-day mortality (odds ratio [OR] 1.44; 95% confidence interval [CI] 1.28-1.61) and more hospitalization or emergency department visits (OR, 1.14; 95% CI, 1.09-1.28), with a trend toward a higher incidence of cardiac complications (OR, 1.03; 95% CI, 0.87-1.12) and neurologic complications (OR, 1.23; 95% CI, 0.96-1.58). South Asians had a lower 30-day mortality (OR, 0.88; 95% CI, 0.78-0.98) but a higher incidence of hospitalization or emergency department visits (OR, 1.17; 95% CI, 1.14-1.20) with a trend toward a lower incidence of cardiac complications (OR, 0.76; 95% CI, 0.67-0.87) and neurologic complications (OR, 0.89; 95% CI, 0.73-1.09). There was also a significant difference in these outcomes between wave 1, 2 and 3, with a greater mortality in all groups in waves 2 and 3. Conclusions: Ethnicity continues to be an important determinant of mortality, cardiac and neurologic outcomes, and healthcare use among patients with COVID-19, requiring further studies to understand factors driving these differences.

Contexte: Nous avons déjà présenté les issues cliniques cardiaques et neurologiques chez les Ontariens de descendance chinoise ou sud-asiatique pour la première vague de la pandémie de COVID-19, mais les données au sujet des vagues ultérieures n'avaient pas encore été analysées. Nous présentons ici une prolongation de cette étude de cohortes pour la seconde et la troisième vague de COVID-19. Méthodologie: Notre analyse porte sur des adultes ontariens ayant obtenu un résultat positif à un test de COVID-19 par réaction en chaîne de la polymérase entre le 1er janvier 2020 et le 30 juin 2021. Un algorithme validé pour l'analyse des noms de famille a été utilisé pour isoler les sujets de descendance chinoise ou sud-asiatique, et leur taux de mortalité de même que les complications cardiaques et neurologiques ont été comparés à ceux de la population générale à l'aide de modèles de régression logistique multivariée. Résultats: En comparaison de la population générale (n = 439 977), les personnes de descendance chinoise (n = 15 208) se sont révélées plus âgées (âge moyen de 44,2 ans contre 40,6 ans, P < 0,001), tandis que les personnes de descendance sud-asiatique (n = 46 333) étaient plus jeunes (39,2 ans, P < 0,001). Dans la population de descendance chinoise, le taux de mortalité après 30 jours était plus élevé (rapport de cotes [RC] de 1,44; intervalle de confiance [IC] à 95 % de 1,28 à 1,61), et davantage d'hospitalisations ou de consultations aux urgences sont survenues (RC de 1,14; IC à 95 % de 1,09 à 1,28). L'incidence de complications cardiaques (RC de 1,03; IC à 95 % de 0,87 à 1,12) et de complications neurologiques (RC de 1,23; IC à 95 % de 0,96 à 1,58) avait également tendance à être plus élevée. Chez les personnes de descendance sud-asiatique, le taux de mortalité après 30 jours était plus faible (RC de 0,88; IC à 95 % de 0,78 à 0,98), mais l'incidence d'hospitalisations ou de consultations aux urgences était plus élevée (RC de 1,17; IC à 95 % de 1,14 à 1,20). Elles présentaient également une tendance vers une plus faible incidence de complications cardiaques (RC de 0,76; IC à 95 % de 0,67 à 0,87) et de complications neurologiques (RC de 0,89; IC à 95 % de 0,73 à 1,09). Des différences significatives ont également été observées pour ces paramètres entre les vagues 1, 2 et 3 de la maladie, et le taux de mortalité était plus élevé pour tous les groupes des vagues 2 et 3. Conclusions: L'origine ethnique demeure un déterminant important de la mortalité, des issues cliniques cardiaques et neurologiques ainsi que de l'utilisation des ressources en santé chez les patients atteints de la COVID-19. D'autres études sont toutefois nécessaires pour mieux comprendre les facteurs qui expliquent ces différences.

Renin-angiotensin-aldosterone system inhibitors and major cardiovascular events and acute kidney injury in patients with coronary artery disease.

BACKGROUND: Renin-angiotensin-aldosterone system inhibitors (RAASIs) are recommended for most patients with coronary artery disease (CAD). However, there is debate across guidelines as to which patients with CAD benefit the most from these agents. This study investigated the association between RAASIs and cardiovascular outcomes and acute kidney injury in a contemporary cohort of patients with CAD. METHODS: Patients ≥65 years of age with CAD alive on April 1, 2012 in Ontario, Canada were included. Outcomes included major adverse cardiovascular events (MACE: cardiovascular death, myocardial infarction (MI), unstable angina, stroke, or coronary revascularization), and acute kidney injury (AKI) hospitalizations at 4 years. Inverse probability of treatment-weighted Cox proportional hazards regression models was used to compare the rates of each outcome in patients treated with and without RAASIs (angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers). RESULTS: There were 165,058 patients with CAD identified (mean age 75 years, 65.5% male, 64.7% prescribed RAASIs). After inverse-probability weighting, treatment with RAASIs was associated with a lower rate of MACE compared with treatment without RAASIs (17.6% vs 18.2%, hazard ratio [HR]: 0.96, 95% CI: 0.93-0.99, respectively). However, treatment with RAASIs was associated with a higher rate of AKI compared with treatment without RAASIs (1.7% vs 1.5%, HR: 1.14, 95% CI: 1.02-1.29, respectively). The reduction in MACE was greater in patients with prior MI (HR: 0.87, 95% CI: 0.82-0.92) compared with patients without prior MI (HR: 1.00, 95% CI: 0.97-1.04, interaction p < 0.01). The increase in AKI was lower in patients with prior MI (HR: 0.82, 95% CI: 0.66-1.00) compared with patients without prior MI (HR: 1.37, 95% CI: 1.19-1.57, interaction p < 0.01). CONCLUSIONS: This study supports the continued use of RAASIs in patients with CAD, although the benefit appears smaller in magnitude than observed in prior trials. High-risk patients, particularly those with prior MI, appear to benefit the most from RAASIs.

Troponin Testing After Noncardiac Surgery in Ontario: An Observational Study.

BACKGROUND: In 2017, the Canadian Cardiovascular Society (CCS) published guidelines recommending postoperative troponin surveillance in higher-risk patients having major noncardiac surgery. The objective of this study was to evaluate the proportion of major noncardiac surgery patients that would meet recommendations for troponin testing and to assess the rates of troponin testing before guideline adoption. METHODS: We conducted a retrospective observational study of patients age 40 to 105 undergoing a subset of major noncardiac surgeries that included orthopedics, gynecology, general, urology, vascular, and thoracic surgeries in Ontario, Canada from January 1, 2010 to December 31, 2017. The primary outcomes were the proportion of patients recommended for testing based on the guidelines and rates of troponin testing within 2 days of surgery. RESULTS: We identified 257,704 patients who underwent noncardiac surgery. Mean age was 66.4 ± 11.9 years, and 12.4% underwent urgent surgery. Applying the CCS guidelines, 71.2% of elective surgery patients and 81.0% of urgent surgery patients would have met recommendations for postoperative troponin screening, whereas 10.8% and 27.1% received postoperative troponin testing, respectively. Most elective surgery patients met recommendations for testing based on the age criterion (54.9%), followed by diabetes (24.6%) and high-risk surgery (22.7%) criteria. Troponin testing varied substantially by types of surgery: highest for open abdominal aortic aneurisms and lowest for hysterectomies. CONCLUSIONS: Based on the CCS guidelines, most patients undergoing the subset of surgeries assessed would have met recommendations for routine troponin testing. In contrast, routine troponin testing before guideline adoption was done infrequently in Ontario, with substantial variations based on the surgery type.

INTRODUCTION: En 2017, la Société canadienne de cardiologie (SCC) a publié des lignes directrices dont les recommandations portaient sur la surveillance de la troponine en phase postopératoire chez les patients exposés à un risque accru de subir une intervention chirurgicale non cardiaque importante. L'objectif de la présente étude était d'évaluer le nombre de patients subissant une intervention chirurgicale non cardiaque importante qui répondraient aux recommandations sur le dosage de la troponine et de déterminer la fréquence des dosages de la troponine avant l'adoption des lignes directrices. MÉTHODES: Nous avons mené une étude observationnelle rétrospective auprès de patients âgés de 40 à 105 ans subissant des interventions chirurgicales non cardiaques importantes, à savoir des interventions de chirurgie orthopédique, de chirurgie gynécologique, de chirurgie générale, de chirurgie urologique, de chirurgie vasculaire et de chirurgie thoracique en Ontario, au Canada, du 1er janvier 2010 au 31 décembre 2017. Les principaux critères d'évaluation étaient le nombre de patients pour qui le dosage était recommandé selon les lignes directrices, et la fréquence des dosages de la troponine dans les deux jours après l'intervention chirurgicale. RÉSULTATS: Nous avons relevé 257 704 patients qui avaient subi une intervention chirurgicale non cardiaque. L'âge moyen était de 66,4 ± 11,9 ans, et 12,4 % avaient subi une intervention chirurgicale urgente. En appliquant les lignes directrices de la SCC, 71,2 % des patients avaient subi une intervention chirurgicale élective et 81,0 % des patients qui avaient subi une intervention chirurgicale urgente répondaient aux recommandations de dépistage de la troponine en phase postopératoire, alors que respectivement 10,8 % et 27,1 % avaient reçu le dosage de la troponine en phase postopératoire. La plupart des patients qui avaient subi une intervention chirurgicale élective répondaient aux recommandations sur le dosage selon le critère d'âge (54,9 %), puis selon le critère de diabète (24,6 %) et le critère d'intervention chirurgicale à risque élevé (22,7 %). Le dosage de la troponine variait de façon substantielle selon le type d'intervention chirurgicale : le dosage le plus élevé lors des traitements chirurgicaux ouverts des anévrismes de l'artère abdominale et le dosage le plus faible lors d'hystérectomies. CONCLUSIONS: Selon les lignes directrices de la SCC, la plupart des patients qui subissaient les interventions chirurgicales évaluées avaient répondu aux recommandations de dosage systématique de la troponine. En revanche, le dosage systématique de la troponine avant l'adoption des lignes directrices était rarement réalisé en Ontario, et des variations substantielles selon le type d'intervention chirurgicale étaient observées.

Prescribing of two potentially interacting cardiovascular medications in atrial fibrillation patients on direct oral anticoagulants.

BACKGROUND: Amiodarone and diltiazem are commonly recommended cardiovascular medications for use in atrial fibrillation (AF) patients. They are known to have drug-drug interactions (DDIs) with direct oral anticoagulants (DOACs). We aimed to evaluate frequency of use of amiodarone or diltiazem among continuous users of DOACs in AF patients and to determine factors associated with their co-use. METHODS: The study population included all AF patients with continuous DOAC use in Ontario, Canada, ≥66 years, from April 1, 2017 to March 31, 2018. Concurrent use of amiodarone or diltiazem was determined by identifying the presence of an overlapping prescription. Multivariable logistic regression models were used to identify predictors of amiodarone or diltiazem use. RESULTS: In total, 5,390 AF patients, ≥66 years, with continuous DOAC use were identified. Amiodarone was co-prescribed in 6.4% patients and diltiazem was co-prescribed in 11.2% patients. Prior percutaneous coronary intervention (PCI) and coronary artery bypass surgery (CABG) were associated with significantly increased odds of amiodarone co-use (OR 2.51 [95% CI 1.54, 4.09], p = 0.0002 and OR 5.28 [95% CI 3.52, 7.93], p= <0.001, respectively). Patients with a heart failure (HF) history also had increased co-use of amiodarone (OR 2.05 [95% CI 1.57, 2.67], p < 0.001). The presence of chronic obstructive pulmonary disease (COPD) was associated with significantly increased odds of diltiazem co-use (OR 1.58 [95% CI 1.31, 1.9], p=<0.001). CONCLUSIONS: Among AF patients with continuous DOAC use, amiodarone was co-prescribed in 1 in 16 patients and diltiazem was co-prescribed in 1 in 9 patients. Predictors such as history of HF, PCI, CABG or COPD help identify vulnerable populations at increased risk of DDIs.