title: Performance of blood pressure-to-height ratio at a single screening visit for the identification of hypertension in children.
abstract: BACKGROUND
  The diagnosis of hypertension in children is difficult because of the multiple sex-, age-, and height-specific thresholds to define elevated blood pressure (BP). Blood pressure-to-height ratio (BPHR) has been proposed to facilitate the identification of elevated BP in children.
  
  
  OBJECTIVE
  We assessed the performance of BPHR at a single screening visit to identify children with hypertension that is sustained elevated BP.
  
  
  METHODS
  In a school-based study conducted in Switzerland, BP was measured at up to three visits in 5207 children. Children had hypertension if BP was elevated at the three visits. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) for the identification of hypertension were assessed for different thresholds of BPHR. The ability of BPHR at a single screening visit to discriminate children with and without hypertension was evaluated with receiver operating characteristic (ROC) curve analyses.
  
  
  RESULTS
  The prevalence of systolic/diastolic hypertension was 2.2%. Systolic BPHR had a better performance to identify hypertension compared with diastolic BPHR (area under the ROC curve: 0.95 vs. 0.84). The highest performance was obtained with a systolic BPHR threshold set at 0.80 mmHg/cm (sensitivity: 98%; specificity: 85%; PPV: 12%; and NPV: 100%) and a diastolic BPHR threshold set at 0.45 mmHg/cm (sensitivity: 79%; specificity: 70%; PPV: 5%; and NPV: 99%). The PPV was higher among tall or overweight children.
  
  
  CONCLUSIONS
  BPHR at a single screening visit had a high performance to identify hypertension in children, although the low prevalence of hypertension led to a low PPV.
authors.affiliation: aInstitute of Social and Preventive Medicine (IUMSP), Lausanne University Hospital, Lausanne bUniversity Children's Hospital, Inselspital and University of Bern, Bern cService of Nephrology, Lausanne University Hospital, Lausanne, Switzerland dDepartment of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Canada.
authors.forename: Zaïneb
authors.initials: Z
authors.lastname: Outdili
authors.forename: Helena
authors.initials: H
authors.lastname: Marti-Soler
authors.forename: Giacomo D
authors.initials: GD
authors.lastname: Simonetti
authors.forename: Pascal
authors.initials: P
authors.lastname: Bovet
authors.forename: Fred
authors.initials: F
authors.lastname: Paccaud
authors.forename: Michel
authors.initials: M
authors.lastname: Burnier
authors.forename: Gilles
authors.initials: G
authors.lastname: Paradis
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chiolero
mesh_terms: D001794:Blood Pressure; D001827:Body Height; D002648:Child; D006801:Humans; D006973:Hypertension / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013557:Switzerland