Incidence, Characteristics, and Outcomes of Acute Myocardial Infarction among Patients Admitted with Acute Exacerbation of Chronic Obstructive Lung Disease

The frequency, characteristics and outcomes of acute myocardial infarction (AMI) during exacerbation of chronic obstructive pulmonary disease (COPD) are unknown. Adult patients hospitalized with a principle diagnosis of acute COPD exacerbation were identified using retrospective analysis of the Nationwide Inpatient Sample (NIS) from 2003 to 2016. Patients were stratified into 2-groups with and without a secondary diagnosis of AMI. The study's endpoints were in-hospital morbidity, mortality, and resource utilization. We also assessed the impact of invasive management strategy on the same end-points. We included 6 894 712 hospitalizations, of which 56 515 (0.82%) were complicated with AMIs. Patients with AMI were older, and had higher prevalence of known coronary disease (48.9% vs. 27.4%), atrial fibrillation (23.3% vs. 15.2%), heart failure (47.8% vs. 26.2%), and anemia (20.7% vs. 14.8%) (p < 0.001). Rates of oxygen dependence were similar (16.3% vs. 16.1%, p = 0.24). In 56 486 propensity-matched pairs of patients with and without AMI, mortality was higher in the AMI group (12.1% vs. 2.1%, p < 0.001). Rates of major morbidities, non-home discharge, and cost were all higher in the AMI group. A minority (18.1%) of patients with AMI underwent invasive assessment, and those had lower in-hospital mortality before (4.9% vs. 13.8%) and after (5.0% vs. 10.0%) propensity-score matching (p < 0.001). This lower mortality persisted in a sensitivity analysis accounting for immortal time bias. AMI complicates similar to 1% of patients admitted with acute COPD exacerbation, and those have worse outcomes than those without AMI. Invasive management for secondary AMI during acute COPD exacerbation may be associated with improved outcomes but is utilized in <20% of patients.