title: Association between waist circumference and childhood-masked hypertension: A community-based study.
abstract: OBJECTIVE
  The aim of this study is to determine the association between waist circumference (WC) and childhood-masked hypertension.
  
  
  METHODS
  A territory-wide, school-based cohort of 1385 Hong Kong students (672 boys and 713 girls) aged 8-17 years was analysed. The ambulatory blood pressure-monitoring assessment was performed using validated oscillometric recorders (A&D TM-2430 (A&D Inc., Tokyo, Japan)) following American Heart Association's recommendations. Subjects were considered normotensive if their casual blood pressure, 24-h daytime and night-time average systolic blood pressure and diastolic blood pressure (DBP) were <95th percentile. If one or more of the ambulatory blood pressure parameters was ≥95th percentile, subjects would be considered suffering from masked hypertension (MH). Subjects who had three successive casual blood pressure measurements above the 95th percentile were excluded.
  
  
  RESULTS
  By body mass index, 148 (10.7%) subjects were obese, 182 (13.1%) overweight and 359 (25.9%) having larger WC (≥85th percentiles). MH was diagnosed in 217 subjects (15.7%). Subjects with larger WC or obesity were significantly associated with higher 24-h daytime and night-time systolic blood pressure (≥95th percentile) (odds ratios from 1.84 to 2.09 and from 2.07 to 3.54 for larger WC and obese respectively, all P < 0.05) as well as 24-h DBP for larger WC (odds ratio = 2, P = 0.015) than normal subjects adjusted by sex, age and height.
  
  
  CONCLUSIONS
  Waist circumference and body mass index are independent risk factors of childhood and adolescent MH. WC appears a significant associated factor of elevated 24-h DBP in children aged 8-17 years.
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Hung-Kwan
authors.initials: HK
authors.lastname: So
authors.affiliation: Cardiac Medical Unit, Grantham Hospital, Hong Kong, China.
authors.forename: Gabriel Wai-Kwok
authors.initials: GW
authors.lastname: Yip
authors.affiliation: The Nethersole School of Nursing, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Kai-Chow
authors.initials: KC
authors.lastname: Choi
authors.affiliation: Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Albert M
authors.initials: AM
authors.lastname: Li
authors.affiliation: Paediatrics, Kwong Wah Hospital, Hong Kong, China.
authors.forename: Lettie Chuk-Kwan
authors.initials: LC
authors.lastname: Leung
authors.affiliation: Paediatrics, Tuen Mun Hospital, Hong Kong, China.
authors.forename: Sik-Nin
authors.initials: SN
authors.lastname: Wong
authors.affiliation: Clinical Skill Lab, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Rita Yn-Tz
authors.initials: RY
authors.lastname: Sung
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000886:Anthropometry; D001795:Blood Pressure Determination; D018660:Blood Pressure Monitoring, Ambulatory; D015992:Body Mass Index; D002648:Child; D015331:Cohort Studies; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D059468:Masked Hypertension / Q000175:diagnosis* / Q000453:epidemiology*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution; D055105:Waist Circumference / Q000502:physiology*
keywords: ambulatory blood pressure; body mass index; children; masked hypertension; waist circumference