Giving growth hormones to short but otherwise healthy children adds only a modest 2 inches to their height on average, a study found, leading some experts to question whether up to 10 years of daily injections are worth the cost and the trouble.
The 10-year study in today's New England Journal of Medicine is the first long-term look at the controversial practice of administering growth hormones for cosmetic reasons, a use that has not been approved by the Food and Drug Administration.
Dr. Raymond L. Hintz and colleagues at Stanford University showed that about 80 percent of the children studied reached heights greater than would have been expected otherwise. However, the results in individual children varied, and 20 percent saw no height increase.
What's more, few of the children reached the target height set by doctors based on the size of the children's parents.
Dr. Hintz called the results "somewhat disappointing."
"The question is: Do we treat, understanding that it's not a 100 percent guarantee and that it's years of treatment, or do we let nature take its course?" he said. "This is going to be a difficult judgment. I think different parents are going to give different answers."
The American Academy of Pediatrics recommends use of growth hormones only in children who have a deficiency of the hormones; a rare chromosomal abnormality called Turner syndrome that stunts growth in girls; or a chronic kidney disorder that retards growth.
The academy warns that the hormones should not be widely used for cosmetic reasons because they could lead to tumors, diabetes, hip problems or difficulties with self-esteem. This study found no side effects.
Even though the FDA has not approved the drugs for use in short but otherwise healthy children, it is not illegal to do so. Roughly 30,000 children are treated with growth hormones in the United States yearly, and about 20 percent of them don't fit into one of the categories the FDA deems as medically necessary.
One year of growth hormone therapy can cost $10,000 to $25,000.
The new study was paid for in part by Genentech Inc. of South San Francisco, Calif., which holds 67 percent of the U.S. market for growth hormones. Eli Lilly and Co. and Pharmacia & UpJohn also produce growth hormones.
The researchers examined 121 children who were considered short for no known medical reason and were treated with growth hormones for two to 10 years.
Among 80 children who received treatment and who have reached adulthood, both boys and girls were an average of about 2 inches taller than would have been expected otherwise.
In an accompanying editorial, Dr. Sharon E. Oberfield of the College of Physicians and Surgeons of Columbia University called the findings inconclusive but was skeptical of hormone use on healthy children.
"Is short stature a disease? If not, should the most severe short stature be considered a disability warranting treatment?" Dr. Oberfield wrote.