Anemia and CKD Associated With New-Onset AF

TSUKUBA, JAPAN — Anemia and chronic kidney disease (CKD) are independently associated with an increased risk of new-onset atrial fibrillation (AF), and the combination of the two risk factors is synergistic for AF onset, a prospective cohort study indicates^[1].

Dr DongZhu Xu (University of Tsukuba, Japan) and multicenter Japanese colleagues found that over a mean follow-up of 13.8 years, an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73m² was 2.56 times more likely to be associated with new-onset AF on multivariate-adjusted hazard ratio (HR) analysis compared with normal kidney function (P<0.0001).

A hemoglobin of <13 g/dL was also 1.5 times more likely to be associated with new-onset AF on the same multivariable HR analysis compared with a normal hemoglobin level (P<0.0001).

The combination of CKD with anemia was also associated with a threefold higher AF incidence in the same prospective cohort, and this increase in risk was higher than would have been expected from the individual effects of CKD or anemia alone (P=0.0003).

"To our best knowledge this is the first study to show that a combination of anemia and CKD confers a particularly high risk for the incidence of AF," study authors write.

"Furthermore, we showed that subjects with a borderline [hemoglobin] level were at risk for new-onset AF in the CKD group but not in the normal eGFR group.

"Therefore, to prevent AF onset, attention should be paid to the treatment and management of not only CKD but to anemia as well."

The study was published online November 11, 2014 in the American Journal of Cardiology.

The Ibaraki Prefectural Health Study was a large community-based cohort study initiated in 1993. In total, the cohort included 194 333 subjects living in the Ibaraki Prefecture in Japan who completed an annual health checkup in 1993. The current study included 132 250 individuals from this cohort.

Electrocardiograms were obtained at study baseline and at yearly follow-up, while levels of hemoglobin as well as serum creatinine were measured at baseline.

During a mean of 13.8 years of follow-up through 2008, new-onset AF was observed in 1232 subjects, for an incidence rate of 0.16% per year.

Multivariable HRs for the incidence of AF according to eGFR rates and hemoglobin classification showed that the lower both the eGFR as well as hemoglobin levels, the greater the risk of AF.

Multivariable HR* for the Incidence of AF According to eGFR <60 (CKD) and Hemoglobin Levels in Men

Investigators suggested that erythropoiesis-stimulating agents may inhibit new-onset AF in patients with CKD and anemia.

However, a prospective study would be needed to establish the effect of these agents on the prevention of AF in high-risk patients.

The study was supported by grants from a number of government agencies and organizations, including the Ministry of Health, Labor, and Welfare in Japan. The authors have reported they have no relevant financial relationships.

Heartwire from Medscape © 2014  Medscape, LLC

Cite this: Anemia and CKD Associated With New-Onset AF - Medscape - Nov 13, 2014.