title: Discordant prevalence of hypertension using two different automated blood pressure measurement devices: a population-based study in Dar es Salaam (Tanzania).
abstract: OBJECTIVE
  The estimation of blood pressure is dependent on the accuracy of the measurement devices. We compared blood pressure readings obtained with an automated oscillometric arm-cuff device and with an automated oscillometric wrist-cuff device and then assessed the prevalence of defined blood pressure categories.
  
  
  METHODS
  Within a population-based survey in Dar es Salaam (Tanzania), we selected all participants with a blood pressure >/= 160/95 mmHg (n=653) and a random sample of participants with blood pressure <160/95 mmHg (n=662), based on the first blood pressure reading. Blood pressure was reassessed 2 years later for 464 and 410 of the participants, respectively. In these 874 subjects, we compared the prevalence of blood pressure categories as estimated with each device.
  
  
  RESULTS
  Overall, the wrist device gave higher blood pressure readings than the arm device (difference in systolic/diastolic blood pressure: 6.3 +/- 17.3/3.7 +/- 11.8 mmHg, P<0.001). However, the arm device tended to give lower readings than the wrist device for high blood pressure values. The prevalence of blood pressure categories differed substantially depending on which device was used, 29% and 14% for blood pressure <120/80 mmHg (arm device versus wrist device, respectively), 30% and 33% for blood pressure 120-139/80-89 mmHg, 17% and 26% for blood pressure 140-159/90-99 mmHg, 12% and 13% for blood pressure 160-179/100-109 mmHg and 13% and 14% for blood pressure >/= 180/110 mmHg.
  
  
  CONCLUSIONS
  A large discrepancy in the estimated prevalence of blood pressure categories was observed using two different automatic measurement devices. This emphasizes that prevalence estimates based on automatic devices should be considered with caution.
authors.affiliation: Institute of Social and Preventive Medicine, University of Lausanne, Switzerland. arnaud.chiolero@hospvd.ch
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chiolero
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Gervasoni
authors.forename: Anne
authors.initials: A
authors.lastname: Rwebogora
authors.forename: Mashombo
authors.initials: M
authors.lastname: Mkamba
authors.forename: Bernard
authors.initials: B
authors.lastname: Waeber
authors.forename: Fred
authors.initials: F
authors.lastname: Paccaud
authors.forename: Michel
authors.initials: M
authors.lastname: Burnier
authors.forename: Pascal
authors.initials: P
authors.lastname: Bovet
mesh_terms: D000328:Adult; D001132:Arm; D001795:Blood Pressure Determination / Q000295:instrumentation* / Q000592:standards; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009991:Oscillometry; D015995:Prevalence; D013636:Tanzania / Q000453:epidemiology; D014953:Wrist