TY - JOUR
T1 - Is further evaluation for growth hormone (GH) deficiency necessary in fibromyalgia patients with low serum insulin-like growth factor (IGF)-I levels?
AU - Yuen, Kevin C.J.
AU - Bennett, Robert M.
AU - Hryciw, Cheryl A.
AU - Cook, Marie B.
AU - Rhoads, Sharon A.
AU - Cook, David M.
N1 - Funding Information:
K.C.J.Y. is supported by research grants from Pfizer Inc. and the Growth Hormone and IGF Research Society Fellowship.
PY - 2007/2
Y1 - 2007/2
N2 - Objective: Fibromyalgia (FM) is characterized by diffuse pain, fatigue, and sleep disturbances; symptoms that resemble the adult growth hormone (GH) deficiency syndrome. Many FM patients have low serum GH levels, with a hypothesized aetiology of dysregulated GH/insulin-like growth factor (IGF)-I axis. The aim of this study was to assess the GH reserve in FM patients with low serum IGF-I levels using the GH-releasing hormone (GHRH)-arginine test. Design: We retrospectively reviewed the GHRH-arginine data of 77 FM patients with low serum IGF-I levels referred to our tertiary unit over a 4-year period. Results: Of the 77 FM patients, 13 patients (17%) failed the GHRH-arginine test. Further evaluation with pituitary imaging revealed normal pituitary glands (n = 7), coincident microadenomas (n = 4), empty sella (n = 1) and pituitary cyst (n = 1), and relevant medical histories such as previous head injury (n = 4), Sheehan's syndrome (n = 1), and whiplash injury (n = 1). In contrast, the remaining 64 patients (83%) that responded to the GHRH-arginine test demonstrated higher peak GH levels compared to age and BMI-matched controls (n = 24). Conclusion: Our data shows that a subpopulation of FM patients with low serum IGF-I levels will fail the GHRH-arginine test. We, thus, recommend that the GH reserve of these patients should be evaluated further, as GH replacement may potentially improve the symptomatology of those with true GH deficiency. Additionally, the increased GH response rates to GHRH-arginine stimulation in the majority of FM patients with low serum IGF-I levels further supports the hypothesis of a dysregulated GH/IGF-I axis in the pathophysiology of FM.
AB - Objective: Fibromyalgia (FM) is characterized by diffuse pain, fatigue, and sleep disturbances; symptoms that resemble the adult growth hormone (GH) deficiency syndrome. Many FM patients have low serum GH levels, with a hypothesized aetiology of dysregulated GH/insulin-like growth factor (IGF)-I axis. The aim of this study was to assess the GH reserve in FM patients with low serum IGF-I levels using the GH-releasing hormone (GHRH)-arginine test. Design: We retrospectively reviewed the GHRH-arginine data of 77 FM patients with low serum IGF-I levels referred to our tertiary unit over a 4-year period. Results: Of the 77 FM patients, 13 patients (17%) failed the GHRH-arginine test. Further evaluation with pituitary imaging revealed normal pituitary glands (n = 7), coincident microadenomas (n = 4), empty sella (n = 1) and pituitary cyst (n = 1), and relevant medical histories such as previous head injury (n = 4), Sheehan's syndrome (n = 1), and whiplash injury (n = 1). In contrast, the remaining 64 patients (83%) that responded to the GHRH-arginine test demonstrated higher peak GH levels compared to age and BMI-matched controls (n = 24). Conclusion: Our data shows that a subpopulation of FM patients with low serum IGF-I levels will fail the GHRH-arginine test. We, thus, recommend that the GH reserve of these patients should be evaluated further, as GH replacement may potentially improve the symptomatology of those with true GH deficiency. Additionally, the increased GH response rates to GHRH-arginine stimulation in the majority of FM patients with low serum IGF-I levels further supports the hypothesis of a dysregulated GH/IGF-I axis in the pathophysiology of FM.
KW - Arginine
KW - Fibromyalgia
KW - Growth hormone
KW - Growth hormone releasing hormone
KW - Insulin-like growth factor-I
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U2 - 10.1016/j.ghir.2006.12.006
DO - 10.1016/j.ghir.2006.12.006
M3 - Article
C2 - 17289417
AN - SCOPUS:33847309225
SN - 1096-6374
VL - 17
SP - 82
EP - 88
JO - Growth Hormone and IGF Research
JF - Growth Hormone and IGF Research
IS - 1
ER -