The significance of micro- and macrovascular biomarkers on cardiovascular outcome in chronic kidney disease: a prospective cohort study.

Measures of small and large artery dysfunction have not been investigated in a single cohort for the prediction of cardiovascular (CV) events in patients with nondialysed (ND) chronic kidney disease (CKD). This prospective cohort study aimed to determine whether central pulse wave velocity (cPWV), central pulse pressure (CPP) or microvascular post-occlusive reactive hyperaemia area (PORHHA) independently predict CV events and mortality in CKD-ND. A total of 94 stage 1-5 CKD-ND (65.3±13.1 years; estimated glomerular filtration rate 35.3 (22.8-49.4) ml min(-1) per 1.73 m(2)) patients were followed-up for a median of 52 (36-65) months and had baseline cPWV and CPP measured by applanation tonometry and PORHHA by laser Doppler flowmetry. Multiple failure time Cox regression models were used to determine the predictive role of vascular parameters on CV mortality and events. Based on multiple linear regressions, baseline age, diabetes, CV disease, and systolic blood pressure (SBP) were independently related to cPWV (R(2)=0.3), SBP and PORHHA to CPP (R(2)=0.45), whereas CPP was the only parameter independently related to PORHHA (R(2)=0.16, all P<0.05). During follow-up, 41 CV events occurred (14 CV deaths). In univariate analyses, cPWV (1.07 (1.02-1.13) per m s(-1)), CPP (1.04 (1.01-1.07) per mm Hg) and lnPORHHA (0.70 (0.58-0.85) per ln(PU × s)) were all related to the outcome. Baseline diabetes (HR 3.07 (1.65-5.68)), lnFGF23 (fibroblast growth factor-23; 1.86 (1.13-3.06) per RU ml(-1)) and CPP (1.04 (1.01-1.07) per mm Hg) were independent predictors of CV events. The impaired pulsatile component of large arteries (CPP) independently of other vascular markers (cPWV, PORHHA) predicted CV outcomes in CKD-ND. CPP may integrate the information provided by cPWV and PORHHA.