title: Differential effects of age on carotid augmentation index and aortic pulse wave velocity in end-stage renal disease patients.
abstract: BACKGROUND
  In 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.
  
  
  METHODS
  Two 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.
  
  
  RESULTS
  The 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 difference in the older subjects (+0.8%) (interaction between study groups and age: p < 0.001).
  
  
  CONCLUSIONS
  Markedly 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.
authors.affiliation: Department of Internal Medicine, National Yang-Ming University Hospital, Taipei, Taiwan, R.O.C.
authors.forename: Pai-Feng
authors.initials: PF
authors.lastname: Hsu
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: I-Feng
authors.initials: IF
authors.lastname: Lin
authors.forename: Yao-Ping
authors.initials: YP
authors.lastname: Lin
authors.forename: Shao-Yuan
authors.initials: SY
authors.lastname: Chuang
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Cheng
authors.forename: Chen-Huan
authors.initials: CH
authors.lastname: Chen
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001011:Aorta / Q000503:physiopathology*; D002339:Carotid Arteries / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology