Reduced kidney function, albuminuria strongly associated with atrial fibrillation
Patients with kidney damage, manifested as microalbuminuria or macroalbuminuria, or decreased kidney function had a higher atrial fibrillation risk, researchers concluded.
Patients with kidney damage, manifested as microalbuminuria or macroalbuminuria, or decreased kidney function had a higher atrial fibrillation (AF) risk, researchers concluded.
An elevated risk of AF was observed even among individuals with mildly decreased kidney function measured by cystatin C-based glomerular filtration rate (eGFRcys), independent of lifestyle factors, cardiovascular disease, sex, race or hypertension.
In the Atherosclerosis Risk in Communities (ARIC) Study, 10,328 men and women ages 45 to 64 were recruited from four geographically disparate U.S. regions from 1996 to 1998. Participants had four exams, a baseline and three more three years apart. Results appeared online June 6 at Circulation.
Atrial fibrillation was ascertained through the end of 2007 by hospital discharge codes and death certificates. During a median follow-up of 10.1 years, 788 atrial fibrillation cases occurred.
Lower levels of eGFRcys were associated with a higher risk of AF, even after adjustment for potential confounders. Compared to patients with eGFRcys of at least 90 mL • min–1 • 1.73 m–2, patients with National Kidney Foundation classification eGFRcys levels of 60 to 89, 30 to 59, and 15 to 29 mL • min–1 • 1.73 m–2 had multivariable hazard ratios for AF of 1.3, 1.6 and 3.2 (P for trend<0.0001), respectively.
Microalbuminuria and macroalbuminuria were associated with a higher risk, as well. Compared with patients with an albumin-to-creatinine ratio (ACR) less than 30 mg/g, those with an ACR of 30 to 299 mg/g had twice the risk of AF, and for an ACR of 300 mg/g or greater, the risk was increased 3.2 times.
Risk of AF was particularly elevated in those with both low eGFRcys and macroalbuminuria (hazard ratio, 13.1, comparing individuals with ACR≥300 mg/g and eGFRcys of 15 to 29 mL • min–1 • 1.73 m–2 and those with ACR<30 mg/g and eGFRcys≥90 mL • min–1 • 1.73 m–2).
“Given the growing burden of CKD in the general population and the potential for its prevention, future studies should focus on understanding the specific mechanisms underlying this association,” the authors wrote. “Furthermore, strategies for the prevention of AF will have to consider CKD as a preventable risk factor for AF in addition to other well-established risk factors.”