Impact factors of pneumonia in hospitalized patients with acute myocardial infarction

Introduction

Acute myocardial infarction (AMI) may be accompanied by acute, severe, concomitant, noncardiac conditions. The most common concomitant condition was pneumonia. The study objective was to investigate the impact factors of pneumonia in hospitalized patients with AMI.

Methods

A total of 1,443 patients admitted with an AMI were prospectively enrolled in Chinese PLA General Hospital between January 1993 and June 2006. Patients were divided into two groups, based on whether or not the patient was ill with pneumonia within 30 days in hospital. The clinical characteristics, risk factors, clinical treatment and complications were analyzed.

Results

From multivariate logistic regression analysis using pneumonia as a dependent variable and the history, inhospital complications and so on as independent variables, the major determinants of pneumonia were age (OR = 1.983, 95% CI = 1.499–2.623), history of coronary heart disease (OR = 1.566, 95% CI = 1.034–2.371), heart rate (OR = 1.823, 95% CI = 1.452–2.287) and white blood cell count (OR = 1.409, 95% CI = 1.071–1.853) at admission, and complications of heart failure (OR = 3.264, 95% CI = 2.130–5.002), ventricular tachycardia or fibrillation (OR = 2.347, 95% CI = 1.231–4.476), anemia (OR = 2.292, 95% CI = 1.482–3.543) and percutaneous coronary interventions (OR = 0.519, 95% CI = 0.327–0.824).

Conclusion

These findings demonstrate that aging, history of coronary heart disease, heart rate and white blood cell count at admission, and complications of heart failure, ventricular tachycardia or fibrillation, anemia and percutaneous coronary interventions are independent impact factors of pneumonia complicating AMI.