Human growth hormone

Recombinant human growth hormone (HGH) is a synthetic form of a hormone normally produced by the human body. The primary use of HGH is to stimulate lean body mass growth, but it has also been investigated as a treatment to reduce 'buffalo hump' and abdominal fat. One early study found that 11 of 13 treated patients had substantial improvements in fat accumulation. Individuals treated early with HGH had improvement in abdominal fat mass, breast size, and buffalo hump; wasting in the face and limbs was not affected by HGH. However, several people who stopped HGH treatment experienced a return of fat deposits, suggesting that HGH may need to be taken for an indefinite period.1

Two larger, randomised studies of HGH (also known as somatrophin) confirmed that HGH is effective in reducing abdominal fat and boosting lean body mass or muscle. One study from London found that 6mg of HGH daily produced an average increase in lean body mass of 5.2kg while overall weight increased by 2.91kg and trunk fat declined by 1kg.2 A US trial found that visceral abdominal fat diminished significantly in people treated with 4kg HGH daily for 12 weeks.3 Other studies have found some reduction in buffalo hump and/or abdominal fat in some people treated with HGH.4

A key disadvantage with HGH is frequent side-effects including joint pain, hand and foot swelling, and increases in insulin resistance (sometimes leading to diabetes) in the short term.5 6 HGH may not be an appropriate treatment for central fat accumulation when insulin levels are high. Patients in the London study also lost an average of 0.7kg of sub-cutaneous fat, which may be unwelcome in those with severe fat loss.

Human growth hormone is extremely expensive and its cost makes widespread access to HGH through the National Health Service in Britain unlikely. For further information, see Human growth hormone in the section A to Z of other drugs.

Tesamorelin is a growth-hormone-releasing factor analogue that is being studied for possible use in reducing visceral adipose tissue (VAT). It is taken at a dose of 2mg once daily by subcutaneous injection. Tesamorelin has been studied in two randomised, placebo-controlled clinical trials, with results available from a year's follow-up in each. Neither study showed any significant negative impact on glycemic measures. While effective for reducing abdominal fat accumulation, total cholesterol, and triglycerides, it requires continuous use to maintain these benefits over time.7 8

References

  1. Havlir DV et al. Effects of treatment intensification with hydroxyurea in HIV-infected patients with virologic suppression. AIDS 15(11): 1379-1388, 2001
  2. Moyle G et al. Recombinant human growth hormone is effective to treat HIV / AIDS associated wasting in the era of highly active antiretroviral therapy. 14th International Conference on AIDS, Barcelona, abstract LbPeB9012, 2002
  3. Kotler D et al. Growth Hormone (Serostim) effectively reduces viceral adipose tissue (VAT) accumulation and non-HDL cholesterol. Fourteenth International Conference on AIDS, Barcelona, abstract LbOr18, 2002
  4. Tai VW et al. Effects of recombinant human growth hormone on fat distribution in patients with human immunodeficiency virus-associated wasting. Clin Infect Dis 35: 1258-1262, 2002
  5. Lo JC et al. The effects of recombinant human growth hormone on body composition and glucose metabolism in HIV-infected patients with fat accumulation. J Clin Endocrinol Metab 86: 3480-3487, 2001
  6. Moyle GJ et al. Hyperlactataemia and lactic acidosis during antiretroviral therapy: relevance, reproducibility and possible risk factors. AIDS 16: 1341-1349, 2002
  7. Falutz J et al. Long-term safety and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation. AIDS 22(14):1719-1728, 2008
  8. Falutz J et al. Effects of tesamorelin, a growth hormone-releasing factor, in HIV-infected patients with abdominal fat accumulation: a randomised placebo-controlled trial with a safety extension. J Acquir Immune Defic Syndr, advance online publication, 2010