For over three decades, children diagnosed with dwarfism (short stature) have been prescribed Human Growth Hormone (HGH). In these tens of thousands of cases worldwide, short stature syndrome has been successfully - and safely - treated.

The 1990 study by Dr. Rudman of the Medical College of Wisconsin ushered in a new and exciting era for HGH therapy. The improvements seen in lean body mass and associated biological parameters in the study's healthy, elderly men were unprecedented. Adult men and women could look forward to living their later years without becoming fat, flabby, frail, and lethargic. They no longer had to presume that their loss of sex drive, sleeping difficulties, memory changes, and lack of stamina and energy were inevitable.

Nearly a decade and hundreds of clinical studies later, in October 1999 the Johns Hopkins School of Medicine sponsored a Growth Hormone/Growth Factors Symposium. Some of the world's leading endocrinologists and scientific researchers convened to discuss HGH therapy. One of the most notable findings reported at this event was that "GH replacement therapy in adults … is not associated with any increase in mortality."

In 2002, two studies caused undue alarm and confusion on the part of the consumer public relating to HGH safety. Below we bottom-line the outcomes of these studies to clear some of the common misconceptions about HGH therapy in healthy adults.

Q. In the July 27, 2002 issue of The Lancet, Dr. Swerdlow and colleagues in the United Kingdom issued a report of a study that tracked 1,800 people who received HGH as children. Dr. Swerdlow stated that "there were risks about tenfold for colorectal cancer and Hodgkin's disease." Collectively, these people were at a three-fold increased risk of dying from cancer overall. Yet, Dr. Swerdlow also admits that his study was unable to show a direct causative effect between HGH replacement and cancer. What does this all mean?

A. To respond, we point to the study authored by Dr. David Cook, an endocrinologist at Oregon Health and Science University. His report appears in the August 6, 2002 issue of Annals of Internal Medicine, which is the journal of the American College of Physicians & American Society of Internal Medicine. Published just one week after Dr. Swerdlow's study appeared in The Lancet, Dr. Cook presents a compelling scientific argument that counters Dr. Swerdlow's findings.

Dr. Cook explains that epidemiological studies (of which the Swerdlow study is one) often suggest an increase in cancers in normal persons that corresponds to elevated levels of circulating (free) IGF-1. (This may be caused by increased serum concentrations of IGF-1, coupled with reduced levels of the binding proteins that take up IGF-1, which may result from HGH therapy). Dr. Cook submits that naturally-occurring situations in which circulating IGF-1 exist (such as in acromegaly) have not been associated with an increase in cancer. In the words of Dr. Cook, this suggests that "high-normal IGF-1 concentrations may be a marker for cancer but are not causally related to inducement or growth of cancer."

Dr. Cook continues in his report to state that "appropriate growth hormone replacement therapy is associated with normalization, not elevation, of serum IGF-1 concentrations. In addition, levels of binding proteins are increased with growth hormone replacement, along with levels of IGF-1, resulting in normal, not elevated, free IGF-1 concentrations."

Q. In the study by Dr. Blackman et al published in the November 13, 2002 issue of the Journal of the American Medical Association (JAMA), the researchers suggested that the side effects of HGH therapy outweigh potential benefits. The study involved 131 elderly men and women in overall good health, enrolling in a six-month long study of HGH. At the end of the study, the researchers reported that 18 of the HGH-therapy participants experienced carpal tunnel syndrome, joint pain, swollen limbs, diabetes, and blood sugar dysregulation. Is this cause for alarm?

A. Titering of the HGH treatment protocol by the administering physician is absolutely critical in ensuring that neurological and musculoskeletal side effects are avoided. When patients report unusual joint or limb symptoms while taking HGH, a dosage reduction is warranted. Within a matter of days, the reported side effects are eliminated. With regard to the Blackman study, it is important to note that the total duration of the study was six months, which is a very short timeframe that may not have allowed for proper titering to take place prior to the final reporting of both positive and negative effects.

Adult GH replacement therapy may cause transient blood sugar elevation during the course of treatment. However, it is important to understand that short-term blood sugar elevation is not equivalent to diabetic disease. Furthermore, it is a well-known fact of physiology that HGH antagonizes insulin, and in the short-term, elevated blood sugar levels may be experienced during HGH therapy. This correlation has existed in published medical literature for over 30 years. The Blackman study does a disservice to the public by suggesting that adult GH replacement therapy leads to the diabetic state and pancreatic damage. Diabetes is a permanent physiological condition, and a temporary and transient rise in blood sugar as may result from adult GH replacement therapy does not equate with the clinical disease known as diabetes. As of this writing, there is no peer-reviewed published scientific paper implicating adult GH replacement therapy with the onset of a permanent diabetic state.

The Blackman study states that "side effects went away after the hormone treatment was discontinued." This is a testament to the reversible and short-lived involvement of side effects in HGH therapy. The side effect profile of HGH therapy is transient and can be managed effectively by a qualified physician.

Finally, it is important to note that the Blackman study reports a significant benefit to those in the study who received HGH. The report explicitly states that the women in the study "gained an average of 2 to 5 pounds of muscle and lost about five pounds of fat. Men on growth hormone had gained 7 to 10 pounds of muscle and shed about the same amount of fat."

For well over forty years, HGH therapy has been under controlled and careful surveillance and research by the US Food and Drug Administration (FDA) and Centers for Disease Control (CDC). As a result of the monitoring activities of HGH replacement in adults by the FDA, CDC, medical societies overseas (where adult HGH therapy has been in-use longer than the US), and the five major pharmaceutical companies that manufacture HGH, this substance is one of the most extensively and carefully studied drug in history. Yet, not a single one of these entities has attributed any death to the use of HGH replacement when it is administered judiciously by a qualified endocrinologist or anti-aging physician.

Of all of the hormones in-use for adult replacement, HGH has the most extensive history of rigorous scientific trials and practical clinical application. Confusion and alarm have been fueled by media reports that proclaim harm while failing to properly explain the nuances of the study findings. There is a convincing body of literature demonstrating the safety of HGH therapy in the aggregate, however no single large-scale study has yet provided unequivocal evidence of improved health outcomes. As a result, studies involving small populations of adult men and women in good health who are administered HGH, and demonstrate positive benefits, are generally dismissed as "anecdotal." Studies that administered HGH to acutely ill patients fail to provide insight into how HGH therapy affects healthy men and women. We submit that thorough and objective scientific data on adult HGH replacement therapy should continue to be collected through small- and large-scale research studies as well as applied clinical utilization.

REFERENCES:

Blackman et al, "Growth Hormone and Sex Steroid Administration in Healthy Aged Women and Men," J Amer Med Assn, vol, 288(18), Nov. 13, 2002
Cook DM, "Shouldn't adults with growth hormone deficiency be offered growth hormone replacement therapy," Annals of Internal Medicine, 137(3), August 6, 2002.
"Current topics and highlights from the 28th international symposium on GH," Johns Hopkins University School of Medicine, Oct. 22-23, 1999.
Kolata G, "Growth hormone changed older bodies," New York Times, Nov. 13, 2002.
Stenson J, "Growth hormone no fountain of youth," Reuters Health, Nov. 12, 2002.
Swerdlow AJ, Higgins CD, Adlard R, Preece MA. "Risk of cancer in patients treated with human pituitary growth hormone in the UK, 1959-85," The Lancet, 369(9329), July 27, 2002.
Thomas J, "Growth hormone not ready as anti-aging weapon," Healthscout News, Nov. 12, 2002.