Influence of body mass index and gender on human growth hormone HGH responses to HGH-releasing hormone plus arginine and insulin tolerance tests.
Qu XD - J Clin Endocrinol Metab - 01-MAR-2005; 90(3): 1563-9
From NIH/NLM MEDLINE
NLM Citation ID:
15613418 (PubMed)
Full Source Title:
Journal of Clinical Endocrinology and Metabolism
Publication Type:
Clinical Trial; Journal Article
Language:
English
Author Affiliation:
General Clinical Research Center, Harbor-University of California Los Angeles (UCLA) Medical Center, 1000 West Carson Street, Torrance, California 90509, USA.
Authors:
Qu XD; Gaw Gonzalo IT; Al Sayed MY; Cohan P; Christenson PD; Swerdloff RS; Kelly DF; Wang C
Abstract:
The aim of this study is to assess whether gender and body mass index (BMI) should be considered in developing thresholds to define HGH deficiency, using HGH responses to GHRH + arginine (ARG) stimulation and insulin tolerance test (ITT). Thirty-nine healthy subjects (19 males, 20 females; ages 21-50 yr) underwent HGHRH + ARG, and another 27 subjects (19 males, 8 females; ages 20-49 yr) underwent ITT. Peak HGH response was significantly higher (P = 0.005) after HGHRH + ARG than with ITT, and this difference could not be explained by age, gender, or BMI. Peak GH response was negatively correlated with BMI in both tests (HGHRH + ARG, r = -0.76; and ITT, r = -0.65). Peak HGH response to HGHRH + ARG was higher in females than males (P = 0.004; ratio = 2.4), but it was attenuated after eliminating the influence of BMI (P = 0.13; ratio = 1.6). No significant gender differences were found in peak HGH responses to ITT, which could be due to the smaller number of female subjects studied. HGH response to HGHRH + ARG and ITT stimulation is sensitive to BMI differences and less so to gender differences. A higher BMI is associated with a depressed HGH response to both stimulation tests. BMI should therefore be considered as a factor when defining the diagnostic cut-off points in the assessment of HGH deficiency, whereas whether gender should be likewise used is inconclusive from this study.
Major Subjects:
- Arginine / * diagnostic use
- Body Mass Index
- Human Growth Hormone / blood / * deficiency
- Metabolic Diseases / * diagnosis
- Oligopeptides / * diagnostic use
Additional Subjects:
- Adult
- Comparative Study
- Diagnostic Techniques, Endocrine
- Female
- Humans
- Insulin / metabolism
- Insulin Resistance
- Male
- Middle Aged
- Research Support, U.S. Gov't, P.H.S.
- Sex Characteristics
Chemical Compound Name:
(Oligopeptides); 11061-68-0(Insulin); 12629-01-5(Human Growth Hormone); 74-79-3(Arginine); 87616-84-0(growth hormone releasing hexapeptide)
Grant ID:
K23 RR 17298 RR NCRR; M01 RR 00865 RR NCRR; R01 NS 40777 NS NINDS; T32 DK07571 DK NIDDK