Baseline characteristics and serum IGF1 levels in GH deficient (GHD) patients treated in the transition phase from adolescence into adulthood: data from the NordiNet International Outcome Study (IOS)
Matthias M Weber1, Oliver Blankenstein2, Jens Otto L Jørgensen3, Birgitte T Pedersen4, Viatcheslav Rakov5 & Jens Sandahl Christiansen3
Background: Data from several clinical studies have demonstrated the benefit of GH treatment in relation to bone mineral density and body composition in young adults who received GH treatment in childhood due to GHD13. There are recommendations to use a higher GH dose in the transition phase compared to the GH dose required during adulthood to mimic the endogenous GH secretion4,5.
Methods: Data from NordiNet IOS have been analyzed to determine the number of patients recently treated in the transition phase and to obtain the baseline characteristics in these patients and treatment dynamic over 2 years. Selection criteria for this cohort: male patients above 16 years and female patients above 15 years at the time of dosage reduction from growth promoting (adolescent) dose to a lowered transition dose (paediatric database); patients with childhood onset of GHD who were on an ongoing GH treatment at age >18 years and <25 (adult database). All patients had to have at least 2 years of follow up in the transition phase.
Results: Patients in transition were identified in the NordiNet IOS database (15 females and 18 males). The mean age at transition GH dose start was 19.0±2.3 years. Mean BMI was 23.7±3.3, mean IGF1 SDS was −1.2±2.6, mean absolute GH dose was 0.74±0.57 mg/day. The GH dose was higher than generally in the adult GHD population, where mean GH dose is between 0.2 and 0.4 mg/day at treatment start in accordance with the NordiNet IOS database. After 2 years of GH treatment we observed a normalizing of the mean IGF1 SDS up to −0.39±1.95. The mean dose of GH after 2 years of treatment in this patient population was 0.79±0.57 mg/day. It was slightly higher in female than in male patients: 0.93±0.63 vs 0.71±0.44 mg/day respectively.
Conclusion: Transition patients seem to be underrepresented in the database comprising about 4000 children and adults with GHD. At the time of the transition dose start, these patients are characterized by a relatively low IGF1 serum level which normalizes during the GH treatment course. Initial GH dose in transition patients is higher comparing to the initial dose in patients with an adult GHD onset.
References: 1. Attanasio et al. 2004.
2. Conway et al. 2009.
3. Vahl et al. 2000.
4. Nguyen et al. 2009.
5. Clayton et al. 2005.