From the FDA Drug Label
A long-term, open-label, multicenter study was conducted to examine the safety and efficacy of Nutropin in pediatric patients with ISS, also called non-growth hormone deficient short stature For the first year, 122 pre-pubertal subjects over the age of 5 years with stimulated serum GH ≥ 10 ng/mL were randomized into two treatment groups of approximately equal size; one group was treated with Nutropin 0. 3 mg/kg weekly divided into three doses per week and the other group served as untreated controls. Adult height was greater than pretreatment predicted adult height in 49 of 60 males (82%) and 19 of 23 females (83%). The mean difference between adult height and pretreatment predicted adult height was 5.2 cm (2.0 inches) in males and 6.0 cm (2.4 inches) in females (p < 0. 0001 for both).
The currently known long-term effects of HGH treatment in children with idiopathic short stature include:
- An increase in adult height compared to pretreatment predicted adult height
- A mean difference between adult height and pretreatment predicted adult height of 5.2 cm in males and 6.0 cm in females
- Improved height SDS with a mean increase of 0.7 in males and 0.9 in females
- Increased IGF-I levels with a mean increase in IGF-I SDS from -0.9 to -0.2 in Treatment Year 1 1
From the Research
Long-term effects of human growth hormone (HGH) treatment in children with idiopathic short stature include increased adult height, with the greatest benefits seen in those who start treatment younger and continue through puberty. The increase in adult height is typically 3.5-7.5 cm, with a mean difference of 5.7 cm for boys and 6.5 cm for girls, as reported in the collaborative US study sponsored by Genentech 2. Common side effects of HGH treatment include transient glucose intolerance, mild edema, headaches, and joint pain. More concerning long-term effects may include increased risk of type 2 diabetes, potential for slipped capital femoral epiphysis, intracranial hypertension, and scoliosis progression. However, there is no conclusive evidence linking HGH treatment to increased cancer risk or cardiovascular problems, though monitoring is recommended 3.
Some key points to consider when evaluating the long-term effects of HGH treatment in children with idiopathic short stature include:
- The safety profile of HGH treatment is similar to or better than the profile seen in other HGH-treated conditions 3
- The predicted height may be inaccurate and is not an absolute criterion for HGH treatment decisions 4
- Successful first-year response to HGH treatment includes an increase in height SDS of more than 0.3-0.5 4
- IGF-I levels may be helpful in assessing compliance and HGH sensitivity; levels that are consistently elevated (>2.5 SDS) should prompt consideration of HGH dose reduction 4
Treatment typically involves daily subcutaneous injections of somatropin at 0.16-0.3 mg/kg/week until growth plates close or height velocity drops below 2 cm/year, as recommended by the Growth Hormone Research Society, the Lawson Wilkins Pediatric Endocrine Society, and the European Society for Paediatric Endocrinology Workshop 4. Regular monitoring of growth velocity, bone age, glucose levels, and thyroid function is essential. While HGH treatment effectively increases height, the psychological benefits remain debated, and the cost-benefit ratio must be carefully considered given the treatment's high expense and limited coverage by insurance for idiopathic short stature 5, 6.