title: Toward a definition of masked hypertension and white-coat hypertension among hemodialysis patients.
abstract: OBJECTIVE
  Among people with essential hypertension, ambulatory BP measurement is superior to BP obtained in the clinic in predicting cardiovascular outcomes. In part, this is because it can detect white-coat hypertension and masked hypertension. Whether the same is true for hemodialysis patients is not known.
  
  
  METHODS
  Using a threshold of 140/80 mmHg for median midweek dialysis-unit BP and 135/85 mmHg for 44-hour ambulatory BP, we defined four categories of BP: sustained normotension (SN), white-coat hypertension (WCH), masked hypertension (MHTN), and sustained hypertension (SHTN).
  
  
  RESULTS
  Among 355 long-term hemodialysis patients, the prevalence of SN was 35%, WCH 15%, MHTN 15%, and SHTN 35%. Over a mean follow-up of 29.6 (SD 21.7) months, 102 patients died (29%), yielding a crude mortality rate of 121/1000 patient-years. Unadjusted and multivariate-adjusted analyses showed increasing all-cause mortality with increasing severity of hypertension (unadjusted hazard ratios from SN, WCH, MHTN, SHTN: 1, 1.12, 1.70, 1.80, respectively [P for trend < 0.01]; adjusted hazard ratios: 1, 1.30, 1.36, 1.87, respectively [P for trend 0.02]). When a predialysis BP threshold of 140/90 mmHg was used to classify patients into BP categories, the prevalence of SN was 24%, WCH 26%, MHTN 4%, and SHTN 47%. Hazard ratios for mortality were similar when compared with median midweek dialysis-unit BP.
  
  
  CONCLUSIONS
  As in the essential hypertension population, MHTN and WCH have prognostic significance. The prognostic value of BP obtained in the dialysis unit can be refined with ambulatory BP monitoring.
authors: Professor of Medicine, Indiana University and Veterans Administration Medical Center, 1481 West 10th Street, Indianapolis, IN 46202, USA. ragarwal@iupui.edu
authors: Rajiv
authors: R
authors: Agarwal
authors: Arjun D
authors: AD
authors: Sinha
authors: Robert P
authors: RP
authors: Light
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D001795:Blood Pressure Determination; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007196:Indiana; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D059468:Masked Hypertension / Q000145:classification / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D008875:Middle Aged; D009819:Office Visits; D011237:Predictive Value of Tests; D015995:Prevalence; D016016:Proportional Hazards Models; D006435:Renal Dialysis / Q000009:adverse effects / Q000401:mortality; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D009626:Terminology as Topic; D013997:Time Factors; D059466:White Coat Hypertension / Q000145:classification / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology