Abstract 2451: Chronic Kidney Disease as an Independent Risk Factor for New-Onset Atrial Fibrillation in Patients with Essential Hypertension

Abstract

Atrial fibrillation (AF) is frequently observed in hypertensive heart disease. Older age, increased left ventricular (LV) mass, and left atrial (LA) dilatation are known to be risk factors for the occurrence of AF in hypertensive patients. Chronic kidney disease (CKD) has recently been recognized to be a powerful risk for cardiovascular events. However, no study has revealed the association between CKD and the onset of AF. Thus, the present study assessed the hypothesis that CKD may influence the onset of AF in hypertensives. A total of 1,118 essential hypertensive patients (mean age, 63 years) without previous paroxysmal AF, heart failure, myocardial infarction, valvular disease, or LV asynergy were enrolled. In echocardiographic examinations, LA dimension and LV mass index (LVMI) were determined. Estimated glomerular filtration rate (eGFR) was calculated by the modified MDRD formula. During follow-up periods (mean, 4.7 years), fifty-seven cases of new onset AF (including paroxysmal AF) were found (1.1% /year). Cumulative event-free rates by the Kaplan-Meier method were decreased according to the decrease in basal eGFR (≥60, 30 – 60, 15–30, and <15 mL/min) and the increase in proteinuria (−/±, 1+/2+, and ≥3+) (log-rank test P<0.001, respectively). When CKD was defined as decreased eGFR (<60 mL/min) and/or the presence of proteinuria, the prevalence of new-onset AF was significantly higher in subjects with CKD (n=420) than without CKD (n=698) (7.9% vs 3.4%, P=0.001). Kaplan-Meier curves also revealed the increase in event rates in the CKD group (log-rank test P<0.001). By univariate Cox regression analysis, age, smoking, LA dimension, LVMI, and the presence of CKD were significantly associated with the occurrence of AF during follow-up. Among these possible predictors, older age (HR 1.63 /10 years, P<0.001) and the presence of CKD (HR 2.25, P=0.004) were independent determinants for the onset of AF in multivariate analysis. The present study demonstrated that the complication of CKD in hypertensive patients was a powerful predictor of new-onset AF, independently of LV hypertrophy and LA dilatation. Our findings may provide a new aspect in considering the cardiorenal association in hypertensive diseases.