Hospital readmissions and economic burden associated with multivessel disease in the early period following acute myocardial infarction

Abstract

Background There is emerging evidence that particularly high rates of major adverse cardiovascular events (MACE) occur in the 90-day period after acute myocardial infarction (AMI). Post-AMI MACE are associated with additional resource utilization and economic burden for healthcare systems, with multivessel disease (MVD) conferring a 3- to 4-fold increase in risk of recurrent MACE in the first year post AMI vs. single vessel disease. Thus, characterizing the prevalence and outcomes of patients with MVD and various comorbidities is crucial to predict and mitigate clinical risk and associated costs. Purpose To describe post-AMI readmissions and economic burden in MVD patients at 30, 90, and 365 days. Methods This was a retrospective cohort study (1st January, 2008 to 31st December, 2018). Patients with MVD were identified by a confirmed diagnosis code from a longitudinal, representative UK population health dataset comprising primary care data from the Clinical Practice Research Datalink (CPRD), which was linked to secondary care data from the Hospital Episode Statistics (HES) and Office of National Statistics (ONS) databases. Patients who experienced at least one AMI after their first recorded MVD diagnosis were defined as MVD+. A MACE was defined as any one of non-fatal MI, non-fatal stroke, or cardiovascular death. Readmissions were defined as non-elective admissions with a MACE outcome diagnosis occurring up to 28 days from a previous admission with the same treatment speciality. Results The study population included 78,128 MVD+ patients (4.2% of the total patient population). In the MVD+ cohort, 3,753 (4.8%) patients were readmitted with at least one MACE event or other non-elective admission within the cardiovascular specialty: 2,394 (63.8%), 2,562 (68.3%), and 2,830 (75.4%) readmissions occurred within 30, 90, and 365 days, respectively. The mean length of hospital stay per patient, per readmission for MACE within 30, 90, and 365 days was 7.22, 7.46, and 7.74 days, respectively. The mean cost per MACE admission within 90 days of index AMI was £3,926.52. Non-fatal MI was the most common reason for readmission at all timepoints. Percutaneous transluminal balloon angioplasty and saphenous vein graft procedures (coronary artery bypass graft, CABG) were among the most common cardiac procedures in MVD+ patients, at 70,276 (22.7%) and 15,418 (5.0%), respectively. Conclusions In patients with MVD who suffer an AMI, there is high resource utilization and cost, particularly in the first 90-days post AMI; therefore, the 90-day post-AMI period represents significant economic costs to healthcare systems. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): CSL Behring