Impact of multiple myeloma on outcomes of acute myocardial infarction: A propensity score matched analysis.

e24027 Background: Patients with multiple myeloma (MM) are at increased risk of cardiovascular events secondary to its complications and adverse effects of pharmacotherapy. However, data on in-hospital outcomes of MM on acute myocardial infarction (AMI) is limited due to the clinical scenario being relatively uncommon. Thus, we conducted a retrospective study to investigate the in-hospital outcomes and resource utilization of AMI admissions in MM patients. Methods: We extracted data from the National Inpatient Sample (NIS) Database from 2016 to 2020. We included all admissions ≥18 years old with a principal diagnosis of AMI with and without co-morbid MM using International Classification of Diseases Tenth Revision (ICD-10) codes. Propensity score matching was performed to balance hospital characteristics, patient demographics and comorbidities between the two groups. Univariate logistic regression was performed in the balanced cohorts. The primary outcome was inpatient mortality. Analysis was performed using STATA-MP, version 14. 2. Results: A total of 3, 191, 049 hospitalizations for AMI were identified between 2016 and 2020, of which 6, 565 (0. 21%) had co-morbid MM. After propensity score matching, compared to those without MM, admissions for AMI with MM had higher odds ratio (OR) of mortality (OR 1. 51, 95% CI 1. 1-2. 08, p = 0. 01). Similar rates of complications such as respiratory failure, cardiogenic shock, stroke and vascular complications were seen between the two cohorts. However, acute kidney injury was more common in patients with MM (OR 1. 81, 95% CI 1. 52-2. 14, p < 0. 01). Compared to those without MM, admissions for AMI with MM were less likely to undergo coronary angiogram (OR 0. 73, 95% 0. 63-0. 86, p < 0. 01), percutaneous coronary intervention (PCI) (OR 0. 71, 95% CI 0. 60-0. 84, p < 0. 01) or coronary artery bypass grafting (CABG) (OR 0. 52, 95% CI 0. 37-0. 71, p < 0. 01). There was no difference in the length of stay but median hospitalization charges were higher in the cohort with MM (54, 125 vs 58, 493, p < 0. 01). Conclusions: Despite similar complication rates, patients with multiple myeloma (MM) who presented with acute myocardial infarction (AMI) experienced higher in-hospital mortality compared to those without MM. One plausible explanation is that patients with MM were less likely to undergo definitive management procedures such as coronary angiogram, percutaneous coronary intervention (PCI), or coronary artery bypass grafting (CABG) during their admission, as observed in our study. Alternatively, MM might independently predict worse outcomes for AMI. Further research is needed to understand the interplay between AMI and MM, as well as to identify factors contributing to disparities in outcomes and intervention rates between patients with and without MM.