from Medscape Primary Care
Question: Is there any evidence to support the use of growth hormone (GH) in the treatment of chronic fatigue in the geriatric age group? Where I can learn more about GH and clinical indications for use? Andrea Weiss, PA-C
Response: from Charlene McClure Morris, PA-C, 04/30/2002
The Fountain of Youth Park in St. Augustine, Florida, commemorates where Spanish explorer Ponce de León landed in 1513. Looking for the cure to our ills is often not possible, although we — like the explorers of old — often keep searching. The US Centers for Disease Control and Prevention has defined chronic fatigue syndrome (CFS) as 6 months of fatigue that adversely affects the patient's life in the absence of organic or psychiatric etiologies and the concurrent presence of 4 or more specific symptoms. The diagnosis of CFS is made solely through clinical exclusion, and treatment includes both medical and psychological intervention. This may be especially frustrating to a patient, who may prefer a treatment and cure that does not as yet exist.
Growth hormone (GH) is secreted in a pulse-like manner from the anterior pituitary, primarily in the first hours of sleep and after exercise. Normally diminishing with age, measured GH in a 40-year-old may be the same as that of someone twice his or her age.
At present, there are no studies that have shown a clear association between GH and CFS in any population. Results assessing the role of GH in CFS have not been definitive. In a study of 37 medication-free patients with CFS matched with healthy controls, no deficiency was found in the CFS cohort compared with control. Data from a study comparing nonobese CFS patients (n = 73) with age- and gender-matched healthy controls did show an impairment of GH response during insulin-induced hypoglycemia and lower rates of nocturnal GH secretion in the participants with CFS.
However, because these changes did not cause differences in serum concentrations of insulin-like growth factor (IGF-1), study researchers questioned the clinical effect these findings might have, stating that further studies were needed to determine the importance of GH impairment in patients with CFS.
Only 1 study was located in which patients with CFS were treated with GH therapy. Twenty patients with CFS with peak serum GH levels below 10 mcL during sleep were randomized to receive either GH therapy (6.7 mcg/kg/day) for 12 weeks or placebo. When this treatment period ended, 17 individuals were given GH treatment at the previously identified dosage, leading to significant increases in IGF-1, fat-free body mass, and total body water at 12 months. However, quality of life (assessed by 2 measures) in this cohort did not improve during treatment, but 4 participants resumed work after an extended period of sick leave.
Therapy with GH is expensive — as much as $35,000 a year — and is not reimbursed by most insurance carriers. In addition, use of GH has been associated with development of cancer, hypertension, fluid retention, and carpal tunnel syndrome.[3,4]
In the United States, GH is only approved for use in short-stature children who are GH-deficient. In a recent study of long-term GH treatment in children, most observed adverse effects were related to preexisting medical conditions, with GH treatment being well tolerated overall. In Europe, GH was approved in 2001 for "deficiency states." It is also approved for the treatment of growth retardation due to GH deficiency in 81 countries, Turner's syndrome in 68 countries, and chronic renal failure in 29 countries.
In the absence of large studies of GH treatment for CFS and for other maladies of aging, GH therapy could not be recommended at this point in time. As with many historical occurrences in medicine, perhaps it will be patients and their clinicians who provide impetus for further study of a course of therapy not yet accepted as efficacious.
Shelton DL. Dipping into the fountain of youth. AMNews. December 4, 2000. Available at: http://www.ama- assn.org/ sci-pubs/amnews /pick_00/hls a1204.htm. Accessed April 24, 2002.
National Center for Infectious Diseases. Chronic fatigue syndrome. Available at: http://www.cdc. gov/ncidod/ diseases/ cfs/. Accessed April 16, 2002.
Komaroff AL, Fagioli LR, Geiger AM, et al. An examination of the working case definition of chronic fatigue syndrome. Am J Med. 1996:100:56-64.
Clinical Research for Human Growth Hormone. Easy to follow pharmacokinetics and kenetics for HGH. Available at: http://www.growth hormoneth erapy.net/. Accessed April 24, 2002.
Cleare AJ, Sookdeo SS, Jones J, O'Keane V, Miell JP. Integrity of the growth hormone/insulin-like growth facto system is maintained in patients with chronic fatigue syndrome. J Clin Endocrinol Metab. 2000;85:1433-1439.
Moorkens G, Berwaerts J, Wynants H, Abs R. Characterization of pituitary function with emphasis on GH secretion in the chronic fatigue syndrome. Clin Endocrinol (Oxf). 2000;53:99-106.
Moorkens G, Wynants H, Abs R. Effect of growth hormone treatment in patients with chronic fatigue syndrome: a preliminary study. Growth Horm IGF Res. 1998;8(suppl):B131-B133.
Bercu BB, Murray FT, Frasier SD, et al. Long-term therapy with recombinant human growth hormone (Saizen) in children with idiopathic and organic growth hormone deficiency. Endocrine. 2000;15:43-49.
Doctor's Guide. Europe approves Saizen (somatropin) for adult growth hormone deficiency. Available at: http://www.psl group.com/dg /20398E.htm. Accessed April 24, 2002.
Fresh warning against 'anti-aging' medicine issued by expert panel. Medscape Wire; March 4, 2002. Available at: http://www.medscape.com/ viewarticle/429324? srcmp=pc-030802. Accessed April 24, 2002.
Growth hormone, alendronate and tissue-selective estrogen all effective in osteoporosis. Program and abstracts of the 83rd Annual Meeting of the Endocrine Society; June 20-23, 2001; Denver, Colorado. Available at:
http://www.docguide. com/news/content.nsf/ news/5044993F01771 3FE85256A72004E58 2D?OpenDocument&am p;id=F7ACD667 7FBDD879852 56B5B00488 662&count =10&h ighlight=0. Accessed April 24, 2002.
Landis CA, Lentz MJ, Rothermel J, et al. Decreased nocturnal levels of prolactin and growth hormone in women with fibromyalgia. J Clin Endocrinol Metab. 2001;86:1672-1678.
Rosenfeld RG. Is growth hormone just a tall story? [Editorial]. J Pediatr. 1997;130:172-173.
Vance ML, Mauras N. Growth hormone therapy in adults and children. N Engl J Med. 1999;341:1206-1215.