Epidemiology of hypertension in children.

In 1979-80, a cross-sectional study was carried out in 7118 Neapolitan school children aged 10-15 years. In 1980-81 and 1981-82 a longitudinal study was performed in a group of children with blood pressure above the mean + 1SD (in age and sex related peers) and in a group with blood pressure less than mean + 1SD. In the whole population blood pressure increased with age from 10 to 14 years. The major determinant of blood pressure was body weight, followed by heart rate. Three hundred and ninety-eight children (5.6%) were hypertensive having blood pressure greater than mean + 2SD. In children followed longitudinally, blood pressure was very labile; only 13 per cent of those originally having blood pressure mean + 1SD, in fact, remained in the same category. All of these, however, had blood pressure greater than mean + 2SD throughout the study.