Reduction of steroid replacement therapy in patients with congenital adrenal hyperplasia in the transition period from child- to adulthood

Congenital adrenal hyperplasia (CAH) requires life-long glucocorticoid and in case of the salt-wasting form mineralocorticoid replacement therapy. Optimal glucocorticoid dosing necessitates age-specific adjustment, and inadequate replacement therapy risks severe adverse effects. To date, dose adjustment in adults is based on clinical experience without evidence from controlled studies.

We analyzed 24 patients with salt-wasting 21-hydroxylase deficiency with respect to adjustments in their glucocorticoid replacement therapy during the transition period. 13 of these patients were male with a mean body weight of 75±13.5kg (mean±SD), height 173±6.8cm, BMI 25.1±3.9 and an age at transistion of 28.2±9.3 years. The females (n=11) were aged 29.9±9.6 years at transition with a mean body weight of 68.7±13kg, mean height of 160.1±4.5cm and a mean BMI of 26.9±5.4. For glucocorticoid replacement treatment prednisone was used in 50%, prednisolone in 23%, hydrocortisone in 18% and dexamethasone in 9% of cases. Dosages were calculated in glucocorticoid dose equivalents (GDE). Dose adjustment was based on clinical, biochemical and hormonal parameters. The mean dose of glucocorticoid replacement was 0.47 GDE/kg in males and 0.44 in females before transition. After transition glucocorticoid dosages could be reduced to 0.41 GDE/kg in males and 0.39 in females. The mean daily dose of hydrocortisone at transition could be reduced from 30.6 to 25mg/d, the mean dose of prednisolone and prednisone from 9.2 to 8.3mg/d and the mean dose of dexamethasone remained at 0.5mg/d.

Dosage reduction was usually not necessary in patients aged below 30 years (average dosage adjustment: -4%), whereas in patients older than 30 years the median dosage reduction was -26%. These cross-sectional data underline the importance of re-evaluation of the replacement therapy in CAH patients at transition which often results in a reduction of steroid substitution. However, these clinical observations need to be evaluated in a standardized prospective trial in the future.