title: Masked hypertension: different blood pressure measurement methodology and risk factors in a working population.
abstract: OBJECTIVE
  To estimate the prevalence of masked hypertension when the same ambulatory device is used for both manual and ambulatory blood pressure measurements and to measure associations with lifestyle risk factors in a working population.
  
  
  METHODS
  White-collar workers were recruited from three public organizations. Blood pressure was measured at the workplace using Spacelabs 90207 for manual measurements (mean of the first three readings taken by a trained assistant) followed by ambulatory measurements (mean of every other reading obtained during the working day). Masked hypertension was defined as manual blood pressure measurement of less than 140/90 mmHg and ambulatory blood pressure measurement of at least 135/85 mmHg. Smoking, alcohol intake, BMI and leisure physical activity were also assessed.
  
  
  RESULTS
  Blood pressure measurements were obtained from 2370 workers (80% participation, 61% women; mean age = 44 years). Masked hypertension was diagnosed in 15.02% of the participants. The prevalence was higher in men [adjusted odds ratio (OR) = 2.38, 95% confidence interval (CI) = 1.86-3.05]. The prevalence in men increased with age (adjusted OR = 2.08 for 40-49 years, 95% CI = 1.33-3.26 and adjusted OR = 1.91 for > or =50 years, 95% CI = 1.20-3.04) and BMI (adjusted OR = 1.78 for BMI > or = 27, 95% CI = 1.21-2.64). The prevalence in women increased with BMI (adjusted OR = 1.65 for BMI > or =27, 95% CI = 1.14-2.39) and alcohol intake (adjusted OR = 2.12 for at least six drinks per week, 95% CI = 1.34-3.35).
  
  
  CONCLUSIONS
  Masked hypertension is frequent and still present when blood pressure is measured out of the office, using the same device for manual and ambulatory measurements. Sex, age, BMI and alcohol intake are associated with masked hypertension.
authors.affiliation: Unité de recherché en santé des populations, Departement de médecine sociale et préventive, Université Laval, Centre hospitalier affilié universitaire de Québec, 1050 Chemin Ste-Foy, Quebec City, QC G1S 4L8, Canada. xavier.trudel.1@ulaval.ca
authors.forename: Xavier
authors.initials: X
authors.lastname: Trudel
authors.forename: Chantal
authors.initials: C
authors.lastname: Brisson
authors.forename: Brigitte
authors.initials: B
authors.lastname: Larocque
authors.forename: Alain
authors.initials: A
authors.lastname: Milot
mesh_terms: D000328:Adult; D000428:Alcohol Drinking; D001795:Blood Pressure Determination / Q000379:methods*; D018660:Blood Pressure Monitoring, Ambulatory; D015992:Body Mass Index; D003971:Diastole; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D013599:Systole