Growth hormone response to growth hormone-releasing hormone is reduced in adult asthmatic patients receiving long-term inhaled corticosteroid treatment.
BACKGROUND
Some studies have demonstrated that the function of the growth hormone (GH)-insulin-like growth factor (IGF)-1 axis is significantly impaired in patients with oral corticosteroid (CS)-induced osteoporosis. The aim of study was to investigate the effects of long-term therapy with inhaled CSs (ICSs) on the hypothalamic-pituitary-GH axis by the GH response to GH-releasing hormone (GHRH), as well as bone turnover, in adult asthmatic patients.


METHODS
Cross-sectional study.


METHODS
Twenty-seven adult subjects with mild-to-moderate persistent asthma (long-term ICS therapy [ie, > 1 year], 20 patients; naive to ICS treatment, 7 patients) and 10 control subjects.


METHODS
Each subject underwent testing with an IV bolus (1 mug/kg) injection of human GHRH, and samples of GH were taken 15 min before the GHRH injection, at 0 min (ie, at the time of GHRH injection), and at 15, 30, 45, 60, and 90 min after injection to obtain values for peak GH and DeltaGH. At baseline, samples of serum IGF-1 and blood-urine were collected for bone turnover markers.


RESULTS
The GH response to GHRH was significantly reduced in asthmatic patients receiving ICSs (peak GH, p < 0.05; and DeltaGH, p < 0.01) in comparison with control subjects and asthmatic patients who were naive to ICS therapy (peak GH and DeltaGH, p < 0.01). Baseline IGF-1 levels were similar in the three groups. Serum osteocalcin, a marker of bone formation, was significantly reduced (p < 0.01) and correlated with GH peak (r(2) = 0.34; p = 0.007) in asthmatic patients who were treated with ICSs.


CONCLUSIONS
We conclude that GH secretion in response to GHRH is significantly reduced in adult asthmatic patients receiving therapy with ICS and that such inhibition could play a negative role in bone metabolism.
Malerba
Mario
M
Department of Internal Medicine, University of Brescia, 1 Divisione di Medicina, Spedali Civili, Piazza Spedali Civili 1, 25100 Brescia, Italy. malerba@master.cci.unibs.it
Bossoni
Simonetta
S
Radaeli
Alessandro
A
Mori
Erica
E
Bonadonna
Stefania
S
Giustina
Andrea
A
Tantucci
Claudio
C
D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects*; D000328:Adult; D000730:Androstadienes / Q000008:administration & dosage / Q000009:adverse effects*; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001249:Asthma / Q000097:blood / Q000188:drug therapy*; D015519:Bone Density / Q000187:drug effects; D016723:Bone Remodeling / Q000187:drug effects; D019819:Budesonide / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D000068298:Fluticasone; D013007:Growth Hormone-Releasing Hormone; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D013223:Statistics as Topic
D000305:Adrenal Cortex Hormones; D000730:Androstadienes; D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D015675:Osteocalcin; D019382:Human Growth Hormone; D019819:Budesonide; D007334:Insulin-Like Growth Factor I; D013007:Growth Hormone-Releasing Hormone; D000068298:Fluticasone