KURASHIKI CITY, OKAYAMA, JAPAN. The main function of the kidneys is to remove excess water and waste products from the blood. The kidneys process about 200 liters of blood and produce about 2 liters of urine every day. An indication of the health of the kidneys can be obtained by evaluating their filtration capacity. An estimated glomerular filtration rate (GFR) above 60 mL/min is usually considered a sign of good kidney function, while a rate below 45 mL/min may indicate chronic kidney failure (CKF). The calculation of GFR is primarily based on the serum creatinine level, but also takes into account results of urine tests, age, gender, and other factors. An adequate kidney function is particularly important for afibbers supplementing with potassium and magnesium since any excess of these vital electrolytes are excreted by the kidneys.

Japanese researchers now report an association between GFR and atrial fibrillation. Their study involved 41,417 citizens (13,956 men) of Kurashiki City who underwent a health-screening test. About 35% of the participants were found to have hypertension, while about 9% had cardiovascular disease. During the medical examination, 676 study participants (1.6%) were found to have atrial fibrillation. Obviously, the real prevalence of afib in the group may have been significantly higher since all cases of paroxysmal afib would not have been picked up by one single electrocardiogram.

The researchers observed a significant inverse correlation between the prevalence of afib and GFR. Thus, the prevalence of afib in the one-third (lower tertile) of participants having an average GFR of 54 mL/min (more specifically 54 mL/min per 1.73 m2) was 2.8% as compared to only 0.9% in the group (high tertile) having an average GFR of 84 mL/min. Not surprisingly, the incidence of afib also increased with age.

The Japanese researchers speculate that the common factor between AF and reduced GFR (kidney disease) is systemic inflammation and suggest that ACE inhibitors and angiotensin receptor blockers may be helpful in preventing both conditions.

Iguchi, Y, et al. Relation of atrial fibrillation to glomerular filtration rate. American Journal of Cardiology, Vol. 102, 2008, pp. 1056-59

Editor's comment: The findings of this study again emphasize the importance of avoiding systemic inflammation. Fortunately, there are many natural anti-inflammatories that will effectively combat inflammation – Zyflamend, beta-sitosterol, bromelain, curcumin, boswellia, Moducare, quercetin, and fish oil.