Abstract
INTRODUCTION: Chronic kidney disease (CKD) raises cardiovascular risk, but its link with the cardio-ankle vascular index (CAVI) in diabetic and non-diabetic patients remains unclear. The aim of this study was to clarify the relationships between CAVI values and an aspect of renal function. METHODS: We investigated the relationships among CAVI values, proteinuria, and the estimated glomerular filtration rate (eGFR) in 4,682 patients enrolled in a multicenter prospective coupling study (patients aged ≥30 years with at least one cardiovascular risk factor) and both eGFR and proteinuria data available. Based on vascular insufficiency guidelines, we classified the patients as having low (<8) or high (≥8) CAVI values. RESULTS: The proteinuria positivity rate differed significantly between the low- and high-CAVI groups, and the difference was significant even after adjusting for age, gender, and other factors. Although direct comparisons showed a higher proportion of CKD (eGFR <60 mL/min/1.73 m(2)) in the high-CAVI group, this difference disappeared after adjustment. We further divided the low- and high-CAVI groups into diabetes mellitus (DM) and no diabetes mellitus (non-DM) subgroups to examine the rate of proteinuria positivity and the percentage of patients with eGFRs <60 mL/min/1.73 m(2). After the multivariate analysis adjustment, the odds ratios for positive proteinuria the high-CAVI group were 1.69 (confidence interval [CI]: 1.08-2.63, p = 0.021) for the non-DM subgroup and 0.91 (95% CI: 0.56-1.47, p = 0.705) for the DM subgroup. The percentage of patients with eGFRs <60 mL/min/1.73 m(2) was not significantly different between the low- and high-CAVI groups in both the DM and non-DM subgroups after the multivariate analysis adjustment (p = 0.088 for non-DM and p = 0.135 for DM). CONCLUSIONS: Proteinuria was associated with a CAVI ≥8 in patients without DM. High arterial stiffness may serve as a surrogate marker for renal damage in non-diabetic patients.