ABSTRACT
BACKGROUND: The blood pressure levels may vary in population because of genetic, ethnic and socio economic factors. Local reference values have to be established to understand the blood pressure variable. METHODS: Blood pressure data of 2278 boys and 2930 girls in the age group of 3-18 years were analysed to study the distribution pattern of systolic blood pressure and diastolic blood pressure and to develop reference values to define hypertension. Blood pressure was measured using standardised techniques in all. The first and fifth phases of Korotkoff sounds were taken as indicative of systolic blood pressure and diastolic blood pressure respectively. Height percentiles were computed for each one year age group. According to percentiles of height 50th, 90th, 95th and 99th percentiles of systolic blood pressure and diastolic blood pressure were estimated for every one year age. RESULTS: The blood pressure (both systolic and diastolic) tends to increase with age. The stepwise regression analysis revealed that the age and height but not gender, are important determinants of blood pressure. Age and height specific, 50th, 90th and 95th and 99th percentiles of systolic and diastolic blood pressure were derived and are presented in tabular form. CONCLUSION: The blood pressure of children and adolescents can be evaluated using the reference table according to body size. The table provided helps to classify blood pressure as normal or pre hypertension and to define different stages of hypertension.