title: Is prehypertension an independent predictor of target organ changes in young-to-middle-aged persons of African descent?
abstract: OBJECTIVE
  We sought to determine whether prehypertension (BP = 120-139/80-89 mmHg) is associated with target organ changes independent of confounders.
  
  
  METHODS
  In 771 participants from a population sample of African ancestry, approximately 46% of whom had hypertension, and approximately 30% prehypertension, organ damage was assessed from echocardiography (left ventricular mass indexed to height2.7, the mean of posterior and septal wall thickness and early-to-late transmitral velocity), 24-h urine samples (urinary albumin-to-creatinine ratio), serum creatinine concentrations, and carotid-femoral pulse wave velocity. Ambulatory blood pressure values that met with prespecified quality control criteria were available in 539 participants.
  
  
  RESULTS
  A greater proportion of hypertensives (P < 0.0001) but not prehypertensives had elevated 24-h blood pressure values as compared with participants with optimal blood pressure values. Before adjustment for confounders, hypertension was associated with all target organ changes (P < 0.0001), and after adjustment, an independent association was noted between hypertension and all target organ changes (P < 0.05-0.005) except albumin-to-creatinine ratio or serum creatinine concentrations. Before adjustment, prehypertension was associated with left ventricular mass indexed to height2.7, mean wall thickness, pulse wave velocity, and early-to-late transmitral velocity (P < 0.05-0.001), but not with other target organ changes. After adjustment, however, prehypertension was not independently associated with target organ changes. Other factors independently associated with target organ changes were age (all target organs), waist circumference (left ventricular mass indexed to height2.7 and early-to-late transmitral velocity) and diabetes mellitus (albumin-to-creatinine ratio and pulse wave velocity). Interactions between prehypertension and any of the alternative risk factors were not independent predictors of target organ changes.
  
  
  CONCLUSIONS
  Although associated with it, prehypertension is not an independent predictor of organ damage in young-to-middle-aged persons of African ancestry.
authors.affiliation: Cardiovascular Pathophysiology and Genomics Research Unit, School of Physiology, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Gavin R
authors.initials: GR
authors.lastname: Norton
authors.forename: Muzi
authors.initials: M
authors.lastname: Maseko
authors.forename: Elena
authors.initials: E
authors.lastname: Libhaber
authors.forename: Carlos D
authors.initials: CD
authors.lastname: Libhaber
authors.forename: Olebogeng H I
authors.initials: OH
authors.lastname: Majane
authors.forename: Patrick
authors.initials: P
authors.lastname: Dessein
authors.forename: Pinhas
authors.initials: P
authors.lastname: Sareli
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Woodiwiss
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D044383:Black People / Q000208:ethnology*; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000208:ethnology* / Q000503:physiopathology; D002339:Carotid Arteries / Q000502:physiology; D003404:Creatinine / Q000097:blood; D005260:Female; D005263:Femoral Artery / Q000502:physiology; D006306:Health Surveys; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000208:ethnology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000208:ethnology / Q000503:physiopathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011673:Pulsatile Flow / Q000502:physiology; D012044:Regression Analysis; D012307:Risk Factors; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D003404:Creatinine