Risk of atrial fibrillation in patients with pneumonia

Background: Cardiac arrhythmias have a strong association with pneumonia due to the cardiovascular response to infection. Electrocardiographic (ECG) changes in patients with pneumonia are associated with greater disease severity. Atrial fibrillation (AF) is the most common type of cardiac arrhythmia. Objective: This population-based cohort study investigated the incidence of AF among Taiwanese adults with pneumonia using data from the National Health Insurance Research Database in Taiwan. Methods: A total of 34,883 patients with pneumonia and an equal number of individuals without pneumonia were eligible after excluding those with a previous diagnosis of AF and matching 1:1 by age, sex, and comorbidities. The Cox proportional hazards model was used to estimate hazard ratios for AF in both groups. Results: Patients were more likely to develop AF throughout the 1-year follow-up period after the diagnosis of pneumonia. The incidence of AF was 1.2 (414/334,746) per 1000 person-months. Patients with pneumonia had a 4.08-fold (95% confidence interval 3.37–4.95) increased risk for AF compared to patients without pneumonia. Conclusion: Patients with pneumonia exhibited an increased risk for AF, especially in the early period after diagnosis of pneumonia.