Stimulated Growth Hormone Concentrations in Obese Pediatric Patients with Mild and Severe Insulin Resistance: A Pilot Study

Background: GH excess predisposes to insulin resistance (IR). Obese patients have blunted responses to GH stimulation and decreased spontaneous secretion. GH secretion has not been studied in the context of IR. Objective: To determine whether varying degrees of IR effects GH dynamics in obese children. Patients/Design: Patients (all > 10 y) were categorized according to gender and HOMA-IR to have either mild or severe IR. Twenty patients (10 female) with mild IR completed the study, as did 18 (9 female) in the severe group. Each patient underwent a GH stimulation test with GHRH. GH peak and area under the curve (AUC) were compared between the groups. Results: Severe IR females had higher peak GH (mean +/- SD, 9.5 +/- 4.4 vs. 5.8 +/- 3.7 ng/dl, p=0.04) and trended toward higher GH AUC (356 +/- 207 vs. 221 +/- 128, p=0.06) than mild IR females. There were no differences in GH response in males, Conclusions: There may be a positive relationship between severity of IR and peak GH in obese girls.