Mortality and risk factors associated with misdiagnosis of acute aortic syndrome in Ontario, Canada: a population-based study.

INTRODUCTION: Acute aortic syndrome (AAS) is a life-threatening aortic emergency. It describes three diagnoses: acute aortic dissection, acute intramural haematoma and penetrating atherosclerotic ulcer. Unfortunately, there are no accurate estimates of the miss rate for AAS, risk factors for missed diagnosis or its effect on outcomes. METHODS: A population-based retrospective cohort study of anonymously linked data for residents of Ontario, Canada, was carried out. Incident cases of AAS were identified between 2003 and 2018 using a validated algorithm based on ICD codes and death. Before multivariate modelling, all categorical variables were analysed for an association with missed AAS diagnosis using χ2 tests. These preliminary analyses were unadjusted for clustering or any covariates. Finally, we performed multilevel logistic regression analysis using a generalised linear mixed model approach to model the probability of a missed case occurring. RESULTS: There were 1299 cases of AAS (age mean (SD) 68.03±14.70, woman 500 (38.5%), rural areas (n=111, 8.55%)) over the study period. Missed cases accounted for 163 (12.5%) of the cohort. Mortality (non-missed AAS 59.7% vs missed AAS 54.6%) and surgical intervention (non-missed AAS 31% vs missed AAS 30.7%) were similar in missed and non-missed cases. However, lower acuity (Canadian triage acuity scale >2 (OR 2.45 95% CI 1.71 to 3.52) (the scale is from 1 to 5, with 1 indicating high acuity) had a higher odds of being a missed case and non-ambulatory presentation (OR 0.47 95% CI 0.33 to 0.67) and presenting to a teaching (OR 0.60 95% CI 0.40 to 0.90)) or cardiac centre (OR 0.41 95% CI 0.27 to 0.62) were associated with a lower odds of being a missed case. CONCLUSIONS: The high rate of misdiagnosis has remained stable for over a decade. Non-teaching and non-cardiac hospitals had a higher incidence of missed cases. Mortality and rates of surgery were not associated with a missed diagnosis of AAS. Educational interventions should be prioritised in non-teaching hospitals and non-cardiac centres.

A Comparison Between the Rates of Radiation Oncologist and Urologist Consultations in Men Diagnosed With Prostate Cancer in Northern Ontario, Canada.

Purpose: Recommendations from Cancer Care Ontario stress the importance of multidisciplinary care from radiologists and urologists for prostate cancer treatment. The present study sought to examine what percentage of patients had a consultation with a radiation oncologist before undergoing a radical prostatectomy in Ontario, Canada, between 2010 and 2019. Methods and Materials: Administrative health care databases were used to analyze the number of consultations billed to the Ontario Health Insurance Plan from radiologists and urologists who treated men with a first prostate cancer diagnosis (n = 22,169). Results: In Ontario, 94.70% of Ontario Health Insurance Plan billings for patients with prostate cancer who had a prostatectomy within 1 year of a prostate cancer diagnosis were from urology, and 37.66% and 1.77% of billings were received from radiation oncology and medical oncology specialties, respectively. When sociodemographic variables were examined, having a lower neighborhood income (adjusted odds ratio [aOR], 0.69; confidence interval [CI], 0.62-0.76) and a rural residence (aOR, 0.72; CI, 0.65-0.79) were associated with lower odds of receiving a consultation from a radiation oncologist. When billings for consultations were examined geographically by region, Northeast Ontario (Local Health Integrated Network 13) had the lowest odds of receiving a radiation consultation compared with the rest of Ontario (aOR, 0.50; CI, 0.42-0.59). Conclusions: The results of this study show that differences in equitable access to multidisciplinary health care exist for men with a first prostate cancer diagnosis who reside in more northern and rural regions within Ontario, relative to the rest of the province. The reasons for these findings are likely multifactorial and may include factors such as patient treatment preference and distance/travel to receive treatment. However, as diagnosis year increased, so did the chances of receiving a radiation oncologist consultation, and this upward trend may reflect the implementation of Cancer Care Ontario guidelines.

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.

Access to Palliative Care for Cancer Patients Living in a Northern and Rural Environment in Ontario, Canada: The Effects of Geographic Region and Rurality on End-of-Life Care in a Population-Based Decedent Cancer Cohort.

BACKGROUND: Access to palliative care has been associated with improving quality of life and reducing the use of potentially aggressive end-of-life care. However, many challenges and barriers exist in providing palliative care to residents in northern and rural settings in Ontario, Canada. AIM: The purpose of this study was to examine access to palliative care and associations with the use of end-of-life care in a decedent cohort of northern and southern, rural and urban, residents. DESIGN: Using linked administrative databases, residents were classified into geographic and rural categories. Regression methods were used to define use and associations of palliative and end-of-life care and death in acute care hospital. SETTING/PARTICIPANTS: A decedent cancer cohort of Ontario residents (2007-2012). RESULTS: Northern rural residents were less likely to receive palliative care (adjusted odds ratio [OR] = 0.90, 95% confidence interval [CI]: 0.83-0.97). Those not receiving palliative care were more likely to receive potentially aggressive end-of-life care and die in an acute care hospital (adjusted OR = 1.20, 95% CI: 1.02-1.41). CONCLUSIONS: Palliative care was significantly associated with reduced use of aggressive end-of-life care; however, disparities exist in rural locations, especially those in the north. Higher usage of emergency department (ED) and hospital resources at end of life in rural locations also reflects differing roles of rural community hospitals compared with urban hospitals. Improving access to palliative care in rural and northern locations is an important care issue and may reduce use of potentially aggressive end-of-life care.