P1.26 MICROVASCULAR REACTIVITY PARAMETERS FAIL TO PREDICT CARDIOVASCULAR EVENTS IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Abstract

Endothelial dysfunction, as assessed by laser-Doppler flowmetry (LDF) is an accepted method to measure microvascular reactivity, which correlates with cardiovascular risk factors in several patient populations. The aim of our prospective cohort study was to assess determinants of LDF parameters and to evaluate their prognostic values in patients with chronic kidney disease (CKD). Ninety four hypertensive, stage 1–5 non-dialysis CKD patients had LDF measurements (iontophoresis of acethylcoline and sodium nitropusside in different doses and postocclusive reactive hyperaemia (PORH)). Baseline associations of these parameters with clinical, hemodynamic and laboratory characteristics were determined by linear regression models. Patients were followed for a median of 43 (37–55) months and the prognostic value of LDF parameters for cardiovascular (CV) events were evaluated by log-rank tests and Cox proportional hazard models. The different LDF parameters did show strong correlation with each other. All iontophoresis parameters were strongly and negatively related to the presence of diabetes or antidiabetic treatment. All PORH parameters were strongly and negatively associated to central pulse pressure and the use of calcium channel blockers. During follow-up 26 CV events occurred. In multivariate analysis, only the presence of diabetes was found to be an independent predictor of CV events (RR: 3.85 (1.66–8.89), p=0.0012). None of the LDF parameters predicted CV outcome. According to our results only the presence of diabetes, but not parameters of microvascular reactivity measured by iontophoresis or PORH have prognostic value for CV events in patients with CKD on conservative therapy. (Supported by Hungarian Kidney Foundation and Hungarian Society of Hypertension).