CONTEXT: Treatment of children with classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is challenging. Linear growth and adult height are compromised according to recent publications. However, most of these data were obtained in the era before CAH newborn screening.

DESIGN: Body height of patients with classical CAH diagnosed before and after the establishment of newborn screening were analyzed retrospectively.

PATIENTS AND METHODS: We identified 600 patients with classical CAH (227 male) with data on near-adult height (NAH), target height (TH), and information on newborn screening from the electronic German CAH registry (DGPAED society). Newborn screening was performed in 101 (16.8%) patients. All patients received hydrocortisone with or without fludrocortisone.To assess the effects of newborn screening, a linear regression model adjusted/stratified for sex and phenotype was used (SAS 9.4).

RESULTS: TH corrected NAH (mean; 95% confidence interval) was closer to zero in patients with CAH and newborn screening (-0.25 SDS; -0.44 - -0.06) than in patients without newborn screening (-0.44 SDS; -0.52 - -0.36) (p=0.069). Screening had no effect on NAH in female patients. In male patients, NAH was significantly better (p=0.033) with screening than without screening. After stratifying for CAH phenotype, screening did not affect the NAH of patients with Salt-wasting-CAH. Patients with Simple-virilizing-CAH had a significantly better cNAH (p=0.034) with screening (0.15 SDS; -0.28 - 0.59) than without screening (-0.35 SDS; -0.52 - -0.18).

CONCLUSIONS: Our data suggest that newborn screening might be associated with improved near-adult height in male CAH patients and in patients with SV-CAH.