Endocrine Abstracts

Introduction: Growth hormone (GH) has multiple metabolic effects in adulthood, pointing to the need of identify those patients who would benefit of GH treatment after achievement of final height.

Objective: To assess GH secretion, bone mineral density (BMD) and metabolic profile in patients with childhood-onset GH deficiency (GHD) after completion of recombinant GH (rGH) therapy for linear growth.

Methodology: One hundred eleven patients (59 males) with childhood-onset GHD were investigated in 2007–2018 at least 3 months after discontinuation of rGH treatment. Permanent GHD was diagnosed when GH peak was less than 10 mU/l during GH stimulation test with insulin and less than 6 mU/l with glucagon. Fasting glycemia, insulin concentration and lipid profile were also assessed. Insulin resistance index (HOMA-IR) was calculated with formula: fasting glycemia (mmol/l) × fasting insulin concentration (mU/l) / 22.5. Bone mineral density (BMD) was determined by dual-energy x-ray absorptiometry (DXA) method (with Hologic Densitometer QDR4500A).

Results: Mean age of patients at the time of retesting was 16.2±1.3, [median 16.33; min 11.4; max 19.6] years. 76 patients had isolated GHD and 35 - multiple pituitary hormone deficiency, – 13 of them PROP1 gene mutation was identified. Twenty four patients (21.6%) have been diagnosed with permanent GHD (4 (5.2%) in the isolated GHD and 20 (57%) in MPHD patients, (P=0.001) and 87 (78.4%) – with transient GHD. Patients with permanent GHD achieved a greater final height compared with transient GHD (−0.4±1.4 vs. −1.4±0.9, respectively, P=0.003). Hypercholesterolemia was significantly more frequent in patients with permanent GHD compared to the transient GHD group (38.9% vs. 6.8%, respectively, P<0.01), HOMA-IR was significantly higher in the group of transient GHD (42.9 vs. 6.7; P=0.009). BMI and BMD were comparable in patients with permanent and transient GHD groups.

Conclusions: 21.6% of patients with childhood-onset GHD were found to have permanent GHD: 5.2% among patients with isolated and 57% in patients with MPHD. Patients with permanent GHD have reached a higher final height than patients with transient GHD. Patients with transient GHD were more insulin resistant, while those with permanent GHD had significantly higher cholesterol levels.