Risk Factors and Prognosis of New-Onset Atrial Fibrillation in Sepsis: A Nationwide Electronic Health Record Study

JACC Adv. 2025 Mar 27;4(4):101681. doi: 10.1016/j.jacadv.2025.101681. Online ahead of print.

Abstract

Background: Atrial fibrillation (AF) may occur in patients with sepsis and is associated with a worse prognosis. To date, no UK nationwide studies have investigated the risks and impact of AF and sepsis.

Objectives: The authors aimed to: 1) identify risk factors contributing to the development of new-onset AF in patients with sepsis; and 2) assess the impact of new-onset AF on in-hospital and long-term outcomes.

Methods: Utilizing linked UK-electronic health records of 5.6 million people between 1998 and 2016, we analyzed risk factors for new-onset AF in the setting of sepsis and assessed duration of hospitalization, rate of septic shock, 7- and 30-day in-hospital mortality, postdischarge mortality, and stroke. Cox proportional hazards models were used to assess postdischarge outcomes, and adjustment for behavioral and demographic variables, and comorbid conditions was performed. Fine-Gray analyses were used to account for competing risks.

Results: We identified 7,691 patients hospitalized for sepsis and new-onset AF, 24,506 patients with sepsis who did not develop new-onset AF, and 95,287 patients hospitalized for new-onset AF who did not have sepsis. Age, sex, ethnicity, socioeconomic deprivation, smoking, chronic obstructive pulmonary disease, heart failure, ischemic heart disease, valvular heart disease, and hypertension were significantly associated with new-onset AF. Compared to sepsis patients without AF, those with new-onset AF during sepsis had longer duration of hospitalization, higher risk of developing septic shock, and higher in-hospital mortality. Patients with sepsis and new-onset AF had a higher rate of stroke (adjusted HR: 1.18; 95% CI: 1.08-1.30), heart failure, myocardial infarction, and mortality postdischarge (adjusted HR: 1.07; 95% CI: 1.03-1.12) than those with sepsis without AF.

Conclusions: AF during sepsis is common and is not an innocent finding. Active monitoring should be pursued as AF has important short- and long-term prognostic implications.

Keywords: arrhythmia; incidence; infection; prognosis; risk factors.