Abstract
BACKGROUND: Chronic obstructive pulmonary disease (COPD), a known risk factor for the development of congestive heart failure (CHF), was recently shown to predict the prevalence of atrial fibrillation (AF). Here, we explore the influence of AF on cardiac prognosis in COPD patients. METHODS: A total of 339 consecutive patients who underwent spirometry from 2010 to 2013 for various reasons were retrospectively examined. Based on the diagnostic criteria, patients were stratified into COPD and non-COPD groups, which were both further divided into those with AF (chronic AF or paroxysmal AF) or sinus rhythm (SR) based on previous electrocardiography results. Significances of differences in cardiac events were assessed by the chi-square test. Multivariate logistic regression analyses and Cox proportional hazard models were applied to evaluate the influence of AF on cardiac events. RESULTS: Of the 339 patients, 190 were diagnosed with COPD, with 42 of these were having AF. During the mean follow-up period of 7.4 ± 0.8 years, CHF developed more frequently in COPD patients with AF than in COPD patients without AF [50% vs 7%; odds ratio (OR) 12.4, 95% confidence interval (CI): 5.25-29.49, p < 0.05]. AF was an independent predictor of CHF development (OR 20.4, 95% CI: 6.55-79.80, p < 0.05) and cardiac mortality (OR 2.8, 95% CI: 1.79-4.72, p < 0.05). Moreover, positive correlations were found between the severity of pulmonary obstruction with AF and CHF development (R = 0.69, p < 0.05), as well as cardiac mortality (R = 0.78.p < 0.05). CONCLUSIONS: These results suggest that AF may be strongly associated with cardiac mortality and CHF in COPD patients.