Age- and height-specific reference limits of blood pressure for Indian children

Background. Blood pressure in childhood is the most powerful predictor of h ypertension in adults. Norms for blood pressure in children are based on th e age- and height-specific distribution of blood pressure in a reference sa mple of healthy children. Methods, We performed a cross-sectional survey of school children in the ag e group 5 to 14 years in south Delhi and studied the distribution of systol ic and diastolic blood pressure in 8293 children (4623 boys and 3670 girls) . Blood pressure was measured in all children with a mercury column sphygmo manometer using a standardized technique. The first and the fourth Korotkof f sounds were taken as indicative of the systolic and the diastolic blood p ressure, respectively. Height percentiles were computed for the study sampl e for every one-year sex-pooled group. Multiple linear regression was then performed for every one-year group in order to estimate the 90th and 95th p ercentiles of systolic and diastolic blood pressure according to percentile s of height. Results. Age and height, but not gender, emerged as the principal determina nts of systolic and diastolic blood pressure in multivariable linear regres sion analyses. Age- and height-specific 90th and 95th percentile values of systolic and diastolic blood pressure were estimated, which enabled us to c ategorize children into 'normal', 'high normal' and 'high' blood pressure g roups. Conclusions, We present age- and height specific reference values for blood pressure of Indian children based on a large study sample. The use of thes e standards should aid the identification of children with high blood press ure.