Frequency of cardiac arrhythmias, the associated risk factors, and in-hospital mortality in patients admitted with community-acquired pneumonia

Background: Community-acquired pneumonia is a common infection that causes significant illness and death globally. Cardiac arrhythmias, particularly atrial fibrillation, are known to be associated with greater disease severity, resulting from cardiovascular effects of an acute episode of pneumonia. Material and Methods: This prospective observational study, included 220 patients aged >18 years with pneumonia, admitted from April 2023 to March 2024, to Aga Khan University Hospital in Karachi, Pakistan. CURB-65 and PSI scores were used to assess disease severity. Patients who were immunocompromised or had a hospital stay of >48 hours prior to development of pneumonia, were excluded. Primary outcomes included frequency of cardiac arrhythmia, whereas secondary outcomes comprised in-hospital mortality, length of hospital stay and occurrence of complications. Results: The study involved 220 patients with a mean age of 66.3 ± 12.7 years. Cardiac arrhythmias were observed in 37 (16.7%) patients, with atrial fibrillation being the most common type, affecting 20 (9%) individuals. Mortality was observed in 37 patients (16.3%). Majority of the patients (37.1%) needed 3-4 days of hospital stay, followed by 34.4% requiring 4-6 days of hospitalization. Patients with severe pneumonia (CURB-65 ≥ 3 and PSI class IV-V) were at greater risk of developing cardiac arrhythmia, which in turn was associated with increased mortality and longer hospital stay. Conclusion: Patients with pneumonia exhibited a greater risk of developing cardiac arrhythmia and associated complications, including longer hospital stay and greater in-hospital mortality. Atrial fibrillation was the most common arrhythmia encountered.