UP to 44% of patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) experience atrial fibrillation (AF). However, there are few data available on the chronicity of AF. Researchers at the Mayo Clinic in Rochester, Minnesota, conducted a retrospective analysis to examine the epidemiology and outcomes of AF in patients with AKI receiving CRRT; the analysis also sought to determine predictors of new-onset AF (NOAF) in CRRT.
The analysis included data on patients admitted to intensive care units (ICUs) at a tertiary care hospital from December 2006 through November 2015 who had AKI and received CRRT. Mortality at 3 years was the primary outcome of interest, assessed using Cox proportional hazard model. In-hospital mortality was a secondary outcome.
A total of 1394 patients receiving CRRT had AKI. Of those, 582 did not have any arrhythmia. Thirty percent (n=419) patients were known to have AF prior to initiation of CRRT. Fourteen percent of patients (n=193) developed NOAF while on CRRT; another 11.5% (n=160) developed NOAF during the index ICU admission prior to CRRT initiation.
There was an independent association between a known history of AF (hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.01-1,41; P=0.04) and NOAF while on CRRT (HR, 1.27; 95% CI, 1.04-1.56; P=0.02) and increased hazard of death within 3 years, compared with those without arrhythmia. The two groups did not differ in in-hospital mortality.
Following adjustment for age, sex, body mass index, SOFA score at initiation of CRRT, baseline serum creatinine, Charlson comorbidity index, number of vasopressors used in the ICU, and use of invasive ventilation, there was an association between higher potassium and increased risk of NOAF on CRRT (HR, 1.24; 95% CI, 1.01-1.54; P=0.043). There was also an association between higher bicarbonate and decreased risk of NOAF on CRRT (HR, 0.95; 95% CI, 0.92-0.98; P=0.003).
In summary, the researchers said, “Incident NOAF in critically ill patients with AKI receiving CRRT is common and carries an unfavorable prognosis similar to patients with prevalent AF. Further studies are required to elucidate modifiable risk factors for NOAF occurring on CRRT and the mechanisms driving the observed association with adverse outcomes.”
Source: Shawwa K, Kompotiatis P, Bobart SA, Wiley BM, Jentzer J, Kashani K. Atrial Fibrillation chronicity in patients with AKI on continuous renal replacement therapy. Abstract of a poster presented at the American Society of Nephrology Kidney Week 2019 (Abstract SA-PO146), November 9, 2019, Washington, DC.