Temporal trends and predictors of emergency department visits and hospital readmissions in angina and no obstructive coronary artery disease (ANOCA): a population-based study of 85,573 adults

Abstract Background Chest pain in patients with angina and no obstructive coronary artery disease (ANOCA) is a diagnostic and treatment challenge, resulting in a significant burden on healthcare resources. With increasing recognition of ANOCA, it is uncertain if the healthcare resource utilization of patients with ANOCA has changed over time. We aimed to determine whether emergency department (ED) visits and hospital readmissions in patients with ANOCA has changed over time and their predictors. Methods A retrospective population-based cohort of patients who had their first cardiac angiography for a chest pain syndrome in Alberta between 2002 and 2020 were extracted from the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database. A temporal trend analysis was performed to investigate the proportion of ED visits and hospital readmissions in ANOCA and obstructive coronary artery disease (CAD). The predictors of ED visits and readmissions were also analyzed. Results In our analysis, 85,573 patients were included (26% ANOCA, 31% female, mean age 62.1 ± 12.0 years, 65% ED visit≥1, 30% readmission). The percentage of patients with ANOCA and obstructive CAD having an ED visit ranged between 26.3% to 30.7% and 47.7% to 53.1%, respectively. The percentage of patients with ANOCA and obstructive CAD having readmission declined slightly over time, from 6.5% to 3.8% in ANOCA and 24.8% to 15.3% in obstructive CAD. Obstructive CAD was found to be the most significant predictor of both ED visits (OR=1.933, 95% CI=1.837–2.034), and readmissions (HR=2.638, 95% CI=2.518–2.764), with congestive heart failure (OR=1.302, 95% CI=1.125–1.507) , peripheral artery disease (OR=1.291, 95% CI=1.116–1.494), cerebrovascular disease (OR=1.382, 95% CI=1.224–1.559), myocardial infarction (vs stable angina (SA): OR=1.233, 95% CI=1.172–1.297), and unstable angina (vs SA: OR=1.564, 95% CI=1.466-1.668–0.89) also contributing to ED visits, and diabetes (HR=1.276, 95% CI=1.229–1.323) and stable angina (vs MI: HR=0.746, 95% CI=0.719–0.774; vs UA: HR=0.895, 95% CI=0.857–0.934) contributing to readmissions. Conclusions Emergency department visits for patients with ANOCA have remained stable over time, with a slight decline in hospital readmissions. Patients with ANOCA had fewer ED visits and readmissions than obstructive CAD patients, and no sex differences were observed in the utilization of healthcare resources. This study suggests that education and follow-up interventions are still needed for patients with ANOCA.Comparison of baseline characteristicsED visits & Readmission Temporal Trends