The Presence of Pneumonia Is Strongly Associated With Higher Prevalence of Non-ST-Elevation Myocardial Infarction Using a Large NIS Database

Abstract

Objective: Inflammation is a risk factor for myocardial infarction. Pneumonia leads to severe inflammatory response. Some studies suggest higher risk of myocardial infarction in patients with pneumonia. We used a large inpatient database (National Inpatient Sample) to evaluate this association.

Methods: This study includes patients from a Nationwide Inpatient Sample hospital in 2005 to 2014 with International Classification of Diseases, Ninth Revision, and Clinical Modification codes consistent with pneumonia and non-ST elevation myocardial infarction (NSTEMI). Subjects were stratified into all hospitalized patients aged 30 and above. Univariate and multivariate analysis was performed adjusting for age, race, gender, tobacco use, diabetes mellitus, hypertension, and hyperlipidemia.

Results: NSTEMI was present in 3.2% of pneumonia patients versus 1.8% in the non-pneumonia population over 10-year period. For example, the 2005 database: [odds ratio (OR), 1.77; 95% confidence interval (CI), 1.73-1.80; P < 0.001]. For 2014, NSTEMI was present in 4.1% of pneumonia patients (PNA) versus 2.4% in the non-pneumonia population (OR, 1.72; 95% CI, 1.70-1.75; P < 0.001). NSTEMI remained independently associated with pneumonia following a multivariate analysis in 2005 (OR, 1.477; 95% CI, 1.447-1.508; P < 0.001) with a similar value in 2014 (OR, 1.445; 95% CI, 1.421-1.469; P < 0.001).

Conclusions: Using a large inpatient database, we found that NSTEMI was strongly associated with PNA versus non-pneumonia population over a 10-year period. Suggesting acute inflammatory cytokines or hypoxia which occurs during lung infection may play a role in NSTEMI development, reinforcing the importance of acute cardiac monitoring in patients with PNA.