Bone turnover and bone mineral density in patients with congenital adrenal hyperplasia

BACKGROUND AND OBJECTIVE Glucocorticoid replacement is the most effective therapy for patients with congenital adrenal hyperplasia (CAH). It has been reported that excessive steroid therapy leads to bone loss and osteoporosis, but it is uncertain whether steroid replacement therapy affects bone turnover and bone mineral density (BMD) in adult patients with CAH. DESIGN Case-control study: patients with CAH were compared to normal subjects, individually matched for age and body weight. PATIENTS Eleven patients, aged 19-65 years, were evaluated in this study. The age at diagnosis of CAH was 0-26 years. Nine patients (6 females and 3 males) were diagnosed with 21-hydroxylase deficiency and 2 male patients with 11-hydroxylase deficiency. 17-Hydroxyprogesterone levels in patients had never been below the reference range in the previous 2 years, These patients were individually matched for sex, age and weight to 11 healthy controls. MEASUREMENTS Total body, lumbar spine and femoral neck BMD was measured by dual-energy X-ray absorptiometry. Serum bone Gla-protein (BGP, osteocalcin) and bone alkaline phosphatase (BAP) were measured to assess bone formation whereas serum tartrate-resistant acid phosphatase (TRAP) and urinary cross-linked N-telopeptides of type I collagen (NTx) were measured to assess bone resorption. NTx was expressed as a fraction of urinary creatinine excretion (NTx/Cr). Serum dehydroepiandrosterone sulphate (DHEA-S) and androstenedione revels were measured to assess adrenal androgen status.