Blood pressure centiles for Great Britain

OBJECTIVE To produce representative cross-sectional blood pressure reference centiles for children and young people living in Great Britain. DESIGN Analysis of blood pressure data from seven nationally representative surveys: Health Surveys for England 1995-8, Scottish Health Surveys 1995 and 1998, and National Diet & Nutrition Survey 1997. METHODS Blood pressure was measured using the Dinamap 8100 with the same protocol throughout. Weight and height were also measured. Data for 11 364 males and 11,537 females aged 4-23 years were included in the analysis, after excluding 0.3% missing or outlying data. Centiles were derived for systolic, diastolic, mean arterial and pulse pressure using the lambda-mu-sigma [corrected] (LMS) equations method. RESULTS Blood pressure in the two sexes was similar in childhood, rising progressively with age and more rapidly during puberty. Systolic pressure rose faster and was appreciably higher in adult men than in adult women. After adjustment for age, blood pressure was related more to weight than height, the effect being stronger for systolic blood pressure. Pulse pressure peaked at 18 years in males and 16 years in females. CONCLUSIONS These centiles increase our knowledge of blood pressure norms in contemporary British children and young people. High blood pressure for age should be defined as blood pressure above the 98th centile, and high-normal blood pressure for age as blood pressure between the 91st and 98th centiles. The centiles identify children and young people with increased blood pressure, and will be of benefit to both clinical practice and research.