Blood pressure in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Background: In patients with congenital adrenal hyperplasia (CAH) recording of blood pressure (BP) must be included in monitoring treatment to detect hypertension. Aim: To investigate the BP patterns in patients with CAH. Methods: Twenty-three children and adolescents (age 6-17 years) and 11 adult patients (age 18-26 years) were studied (21 females, 13 males; 28 salt-wasting patients). In the whole group BP in the outpatient clinic was compared with BP under hospitalisation and in 11 of the children and adolescents also with 24-hour ambulatory blood pressure monitoring (ABPM). Results: BP in the ward in children and adolescents but not in adults was significantly higher than BP in the outpatient clinic, where BP was in the upper normal range. There was also a significant difference between BP in the outpatient clinic and the lower ABPM in the 11 patients tested. Atrial natriuretic peptide (ANP) in blood serum showed normal values. Conclusions: BP measured in outpatients in a relaxed and calm atmosphere meets the requirements for monitoring of treatment. Measurement of BP on the ward leads to falsely high results. ABPM is not necessary. Estimation of ANP provides no additional information.