Raised blood pressure and plasma noradrenaline concentrations in teenagers and young adults selected from an open population.

Plasma noradrenaline (PNA) concentrations were measured in 38 subjects aged 13-23, who were followed up for two to four years after an initial blood-pressure (BP) reading of 140/90 mm Hg or over was obtained, and in 39 age-matched controls from the same open population. Subjects who were hypertensive when the PNA concentration was measured had a significantly higher concentration (351 +/- SE 26 pg/ml) compared with their controls (248 +/- 29 pg/ml). Furthermore, in those subjects in whom the mean arterial pressure decreased by under 5% during the follow-up period the mean concentration was 363 +/- 27 pg/ml, compared with 271 +/- 29 pg/ml in their controls. PNA concentrations and systolic BP were positively correlated. A positive association between PNA concentrations and age was observed in the controls but not the subjects with hypertension, owing to the higher concentrations in younger hypertensive subjects.