Differential Effects of Age on Carotid Augmentation Index and Aortic Pulse Wave Velocity in End-stage Renal Disease Patients

BackgroundIn healthy, normotensive individuals, age-related changes in carotid augmentation index (AI) are more prominent in younger individuals (< 50 years), whereas changes in aortic pulse wave velocity (PWV) are more marked in older individuals (> 50 years). We investigated whether the differential effects of age on AI and PWV also existed in end-stage renal disease (ESRD) patients.MethodsTwo hundred and fifty-seven patients (50% male; mean age, 53.9 ± 15.0 years) with ESRD and 260 normal controls (52% male; mean age, 51.4 ± 17.8 years) received a comprehensive evaluation of cardiovascular structure and function.ResultsThe percent differences in PWV between the younger and older subjects were similar in both ESRD patients (+46.2%) and normal controls (+52.5%). The percent differences in PWV between normal controls and ESRD patients were also similar in both younger (+28.2%) and older (+22.9%) subjects. In contrast, the differences in AI between the younger and older subjects were small in ESRD patients (7.3%) but large in normal controls (19.7%). Furthermore, there was a large difference in AI between normal controls and ESRD patients in the younger (+13.3%) subjects, but no differ-ence in the older subjects (+0.8%) (interaction between study groups and age: p < 0.001).ConclusionMarkedly differential effects of age on AI and PWV were observed in ESRD patients. PWV increased with age similarly in both ESRD patients and normal controls, whereas AI increased markedly in the younger but only slightly in the older ESRD patients. [J Chin Med Assoc 2008;71(4):166–173]