title: Association between routine and standardized blood pressure measurements and left ventricular hypertrophy among patients on hemodialysis.
abstract: BACKGROUND
  Left ventricular (LV) hypertrophy is common among patients on hemodialysis. While a relationship between blood pressure (BP) and LV hypertrophy has been established, it is unclear which BP measurement method is the strongest correlate of LV hypertrophy. We sought to determine agreement between various blood pressure measurement methods, as well as identify which method was the strongest correlate of LV hypertrophy among patients on hemodialysis.
  
  
  METHODS
  This was a post-hoc analysis of data from a randomized controlled trial. We evaluated the agreement between seven BP measurement methods: standardized measurement at baseline; single pre- and post-dialysis, as well as mean intra-dialytic measurement at baseline; and cumulative pre-, intra- and post-dialysis readings (an average of 12 monthly readings based on a single day per month). Agreement was assessed using Lin's concordance correlation coefficient (CCC) and the Bland Altman method. Association between BP measurement method and LV hypertrophy on baseline cardiac MRI was determined using receiver operating characteristic curves and area under the curve (AUC).
  
  
  RESULTS
  Agreement between BP measurement methods in the 39 patients on hemodialysis varied considerably, from a CCC of 0.35 to 0.94, with overlapping 95% confidence intervals. Pre-dialysis measurements were the weakest predictors of LV hypertrophy while standardized, post- and inter-dialytic measurements had similar and strong (AUC 0.79 to 0.80) predictive power for LV hypertrophy.
  
  
  CONCLUSIONS
  A single standardized BP has strong predictive power for LV hypertrophy and performs just as well as more resource intensive cumulative measurements, whereas pre-dialysis blood pressure measurements have the weakest predictive power for LV hypertrophy. Current guidelines, which recommend using pre-dialysis measurements, should be revisited to confirm these results.
authors.affiliation: Department of Medicine, University of British Columbia, Vancouver, Canada.
authors.forename: Jaspreet
authors.initials: J
authors.lastname: Khangura
authors.forename: Bruce F
authors.initials: BF
authors.lastname: Culleton
authors.forename: Braden J
authors.initials: BJ
authors.lastname: Manns
authors.forename: Jianguo
authors.initials: J
authors.lastname: Zhang
authors.forename: Lianne
authors.initials: L
authors.lastname: Barnieh
authors.forename: Michael
authors.initials: M
authors.lastname: Walsh
authors.forename: Scott W
authors.initials: SW
authors.lastname: Klarenbach
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonelli
authors.forename: Magdalena
authors.initials: M
authors.lastname: Sarna
authors.forename: Brenda R
authors.initials: BR
authors.lastname: Hemmelgarn
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000379:methods* / Q000592:standards; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology / Q000628:therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D006435:Renal Dialysis; D016037:Single-Blind Method