Characteristics, clinical management and outcomes of patients with acute myocardial infarction enrolled or not enrolled in a quality registry

Abstract Aims Structured care through enrolment and data collection in quality registries may lead to better care and improved outcomes. We investigated differences in admission characteristics, clinical management and outcomes between patients with acute myocardial infarction enrolled versus non-enrolled in the SWEDEHEART quality registry. Methods and results We linked health records from all hospitalisations (N=47,342) due to a first or recurrent myocardial infarction between 2006–2021 in the region of Stockholm, Sweden, to SWEDEHEART. We compared non-enrolled versus enrolled patients in terms of characteristics, invasive procedures, use of and adherence to guideline-recommended medications, in-hospital mortality, and clinical outcomes after discharge. Non-enrolled participants (N=6,113, 13%) were older, had more chronic kidney disease and other comorbidities. They underwent fewer coronary angiographies and fewer coronary interventions. Non-enrolled participants were less likely to initiate aspirin (HR 0.88, 95% CI 0.84–0.91), beta-blockers (HR 0.87, CI 0.84–0.90), renin-angiotensin system inhibitors (HR 0.73, CI 0.69–0.76), and statins (HR 0.59, CI 0.56– 0.61). They were also less likely to adhere to treatments, in part explained by their comorbid profile. Even after extensive adjustments, non-enrolled patients had higher in-hospital and long-term mortality (HR 1.15, 95% CI 1.09–1.21), and more reinfarction/stroke (HR 1.16, 95% CI 1.08–1.26) than enrolled patients. Conclusions Patients non-enrolled in SWEDEHEART received less evidence-based care, and had worse short- and long-term outcomes. This study identifies a non-negligible population in need of better care, and provides support for the value of structured care models in improving patient outcomes through closer monitoring and better treatment.