New-onset atrial fibrillation in patients with acute kidney injury on continuous renal replacement therapy

PurposeThe mortality of critically ill patients with acute kidney injury (AKI) who require continuous renal replacement therapy (CRRT) remains high. We assessed the incidence and predictors of new-onset atrial fibrillation (NOAF) in this population and its impact on outcomes.Materials and methodsThis is a retrospective cohort study of adult intensive care units (ICU) patients who had AKI and received CRRT from December 2006 through November 2015 in a tertiary academic medical center. Cox proportional hazard model was used to evaluate the impact of NOAF on overall mortality.ResultsOut of 1398 screened patients, NOAF occurred in 193 (14%) cases. NOAF occurring on CRRT was independently associated with an increased hazard of death at follow-up (HR: 1.26; 95% CI: 1.03–1.56), compared to the group who did not have NOAF. In the multivariable analysis using time-dependent covariates, higher potassium (HR 1.24, 95%CI: 1.01–1.54) and bicarbonate (HR 0.95, 95%CI: 0.92–0.98) levels were associated with increased and decreased risk of NOAF on CRRT, respectively.ConclusionsNOAF in critically ill patients with AKI receiving CRRT is common and carries an unfavorable prognosis. Prospective studies are required to elucidate modifiable risk factors for NOAF occurring on CRRT.