Growth Hormone Treatment - Research

Research

Everything discussed in this section involves either studies to see if GH could be useful for other diseases or conditions, or off-label uses that doctors have developed in the course of their daily work. None of the uses described below have been approved by the FDA.

Some of the uses that have been explored relate to stunted growth due to various disorders.

Post-transplant growth failure sometimes improves with GH. Many children who suffer from chronic renal, liver, and heart disease grow poorly for years before a transplant is required (or available). While growth may improve after correction of organ function by successful transplantation, the immunosuppressive drugs taken to protect the transplanted organ may continue to interfere with growth. Growth hormone may help offset these effects and is sometimes offered in these circumstances.

X-linked hypophosphatemic rickets is an inherited disorder of phosphorus metabolism that results in growth failure and rickets. GH has been shown to accelerate growth modestly.

Inflammatory bowel disease (ulcerative colitis and Crohn's disease) can impair growth before producing obvious bowel symptoms. Children with inflammatory bowel disease and Crohn's disease have often GH and IGF-I deficiency and /or GH resistance. Trials of GH have shown at least modest acceleration of growth, but it is unknown whether this actually leads to an increased adult height. Similarly, Coeliac Disease can prevent children from reaching their expected growth potential, if it begins before growth is complete. Stunted growth can be a result of Coeliac Disease damaging the intestines and preventing proper nutrient absorption. Treatment involves a gluten-free diet. HGH treatment has been used in an attempt to recover lost growth due to this effect. A study in the New England Journal of Medicine suggested that HGH might be a beneficial treatment for patients with Crohn's disease.

Poor growth is a part of Noonan syndrome and many other genetic syndromes. Many short children with various syndromes have been treated with GH. As a broad generalization, GH for several years usually produces faster growth, and perhaps 1–2 in (2.5–5.1 cm) of extra adult height.

Small numbers of children with various forms of bone dysplasia (dwarfism in common parlance) have been treated with GH with modest increases in short-term height velocity. No long-term studies have demonstrated increased adult height, and dwarfism due to bone dysplasia remains the prime example of extreme shortness considered not very amenable to GH treatment.

On occasion, GH has been used for other purposes than accelerating growth or replacing deficiency. Nearly every hormone available for administration has been given to non-deficient people in hope of obtaining improvement for various conditions for which other treatments are unsatisfactory. With a few exceptions, benefits are modest and side-effect risk is higher. Experience with GH has yielded the same results. The following is not an exclusive list.

Due to the immunostimulatory effect of GH, it can enhance immunorecevory after radiation in mice and nonhuman primates.

Neurodegenerative diseases (i.e. Alzheimer's disease) are connected with the decline of growth hormone levels, therefore some authors suggest that it is necessary to evaluate the use GH as future antinuerodegenerative strategy.

Other scientists have explored whether hGH treatment could be useful in adults that are not severely deficient in GH. Treatment of healthy, normally aging individuals found the only benefit to be a slight increase in muscle mass, with frequent side-effects and no evidence that it is safe to use long-term.

GH has been given to attempt to promote healing of large burns by reducing the amount of protein breakdown during the early post-injury period.

GH has been used as an adjunct to caloric restriction to attempt to treat obesity. GH promotes lipolysis and reduces proteolysis. It was hoped that GH would reduce muscle breakdown without interfering with use and reduction of fat as the body shifted to a near-starvation economy. Results showed potential benefit, but this has not been widely adopted for a variety of reasons (cost, injections, potential aggravation of insulin resistance, etc.). Recent studies suggest that side-effects, in particular, insulin resistance, may outweigh the potential benefits of such therapy.

Fibromyalgia and chronic fatigue syndrome are poorly understood and vaguely defined conditions with overlapping features. After demonstration of disordered GH secretion and higher rates of tissue breakdown in patients with these conditions, a few people tried growth hormone treatment to see whether energy or healing could be improved. Disturbances of GH secretion may be secondary phenomena and not causal. Despite anecdotal reports of improvement, no large, controlled trials have demonstrated significant, persistent improvement, and GH is not a common or standard treatment for either condition.

GH has been illegally taken by athletes wanting to increase recovery, strength, and power. Some scientific research has been conducted to determine whether such use could be safe and effective—see Growth hormone in sports.