PS-C27-5: ASSOCIATION BETWEEN ANKLE-BRACHIAL INDEX AND KIDNEY OUTCOMES IN PATIENTS WITH HYPERTENSION

Abstract

Background: Ankle-brachial index (ABI) used for diagnosis of peripheral vascular disease is related to endothelial dysfunction. Previous studies showed the relationship between endothelial dysfunction and chronic kidney disease (CKD). Therefore, we aimed to investigate the association between ankle-brachial index and CKD progression in patients with hypertension. Methods: A total of 2,429 patients with hypertension were enrolled from the prospective observational cohort of CMERC-HI (Cardiovascular and Metabolic Disease Etiology Research Center-High Risk). Patients were classified into quartile based on ABI (A1: ABI < 1.11, A2: ABI 1.11 to 1.17, A3: ABI 1.17 to 1.23, A4: ABI> 1.23). Primary outcome was progression of CKD, which was composite of at least 50% decrease in estimated glomerular filtration rate (eGFR) from baseline or end stage kidney disease requiring dialysis, or incident CKD which was defined as eGFR < 60 ml/min/1.73m2. Results: The mean age of study subjects was 60.1 ± 11.3 years and 1,346 (55.4%) were male. There were statistically significant differences in DM status (40.1%, 41.1%, 43.7%, 51.7% in A1, A2, A3, A4 group, respectively, P < 0.001) among ABI quartile groups. During a median follow-up of 42.5 months, the primary outcome met the pre-specified CKD progression in 490 (20.2%). In multivariate Cox analysis, A1 and A3 group were associated with increased risk of CKD progression (HR, 2.28; 95% CI, 1.30–4.00, P = 0.004, HR, 2.22: 95% CI, 1.27–3.90, P = 0.005) compared to A2 group. Moreover, low ABI showed increased risk of CKD progression (HR, 1.57; 95% CI, 1.04–2.38; P = 0.03) after adjusting confounding factors. Conclusions: Ankle-brachial index may be an independent predictor of renal outcome in patients with hypertension.