Factors associated with acute myocardial infarction in older patients after hospitalization with community-acquired pneumonia: a cross-sectional study

Background Community-acquired pneumonia (CAP) and acute myocardial infarction cardiovascular (AMI) are two important health issues in older patients. Little is known regarding characteristics of AMI in older patients hospitalized for CAP. Therefore, we investigated the prevalence, characteristics compared with younger patients, impact on clinical outcomes and risk factors of AMI during hospitalization for CAP in geriatric patients. Methods Eleven thousand nine adult inpatients consisted of 5111 patients >= 65 years and 5898 patients< 65 years in respiratory ward diagnosed with CAP were retrospectively analyzed by electronic medical records. Results 159 (3.1%) older patients in respiratory ward experienced AMI during hospitalization for CAP. AMI were more frequently seen in patients >= 65 years compared with patients< 65 years (3.1% vs. 1.0%). Patients >= 65 years who experienced AMI during hospitalization for CAP had higher percentage of respiratory failure (P = 0.001), hypertension (P = 0.008), dyspnea (P = 0.046), blood urea nitrogen (BUN) >= 7 mmol/L (P < 0.001), serum sodium< 130 mmol/L (P = 0.005) and had higher in-hospital mortality compared to patients< 65 years (10.1% vs. 6.6%). AMI was associated with increased in-hospital mortality (odds ratio, OR, with 95% confidence interval: 1.49 [1.24-1.82]; P < 0.01). Respiratory failure (OR, 1.34 [1.15-1.54]; P < 0.01), preexisting coronary artery disease (OR, 1.31[1.07-1.59]; P = 0.02), diabetes (OR, 1.26 [1.11-1.42]; P = 0.02) and BUN (OR, 1.23 [1.01-1.49]; P = 0.04) were correlated with the occurrence of AMI in the older patients after hospitalization with CAP. Conclusions The incidence of AMI during CAP hospitalization in geriatric patients is notable and have an impact on in-hospital mortality. Respiratory failure, preexisting coronary artery disease, diabetes and BUN was associated with the occurrence of AMI in the older patients after hospitalization with CAP. Particular attention should be paid to older patients with risk factors for AMI.