Impaired Retinal Vessel Dilation Predicts Mortality in End-Stage Renal Disease

Abstract

Rationale : Patients with end-stage renal disease are characterized by increased cardiovascular and all-cause mortality because of advanced remodeling of the macrovascular and microvascular beds. Objective : The aim of this study was to determine whether retinal microvascular function can predict all-cause and cardiovascular mortality in patients with end-stage renal disease. Methods and Results : In the multicenter prospective observational ISAR study (Risk Stratification in End-Stage Renal Disease), data on dynamic retinal vessel analysis were available in a subcohort of 214 dialysis patients (mean age, 62.6±15.0; 32% women). Microvascular dysfunction was quantified by measuring maximum arteriolar dilation and maximum venular dilation (vMax) of retinal vessels in response to flicker light stimulation. During a mean follow-up of 44 months, 55 patients died, including 25 cardiovascular and 30 noncardiovascular fatal events. vMax emerged as a strong independent predictor for all-cause mortality. In the Kaplan-Meier analysis, individuals within the lowest tertile of vMax showed significantly shorter 3-year survival rates than those within the highest tertile (66.9±5.8% versus 92.4±3.3%). Univariate and multivariate hazard ratios for all-cause mortality per SD increase of vMax were 0.62 (0.47–0.82) and 0.65 (0.47–0.91), respectively. Maximum arteriolar dilation and vMax were able to significantly predict nonfatal and fatal cardiovascular events (hazard ratio, 0.74 [0.57–0.97] and 0.78 [0.61–0.99], respectively). Conclusions : Our results provide the first evidence that impaired retinal venular dilation is a strong and independent predictor of all-cause mortality in hemodialyzed end-stage renal disease patients. Dynamic retinal vessel analysis provides added value for prediction of all-cause mortality and may be a novel diagnostic tool to optimize cardiovascular risk stratification in end-stage renal disease and other high-risk cardiovascular cohorts. Clinical Trial Registration : URL: http://www.clinicaltrials.gov . Unique identifier: NCT01152892.