The boys, American-born offspring of immigrants, were healthy, growing normally and on track to be of average height.
"There was no indication of anything abnormal," says Dr. Anna Haddal, pediatric endocrinologist at UCLA. "But the parents still wanted them to be on growth hormone because they wanted them taller. Sometimes parents obtain wealth and they want more for their children." Haddal's anecdote illustrates the kind of case that has had some physicians and ethicists gnashing their teeth over the Food and Drug Administration's 2003 approval of biosynthetic growth hormone for idiopathic short stature, or shortness for no apparent medical reason.
The approval took growth hormone from a drug used since 1985 to treat diseases known to interfere with growth to a drug prescribed for children destined not for dwarfism but for an adult height on the lowest end of the normal bell curve. Under FDA rules, the pharmaceutical industry cannot legally promote unapproved uses of drugs, though off-label prescribing by physicians is legal. With the approval, the industry could begin marketing growth hormone for low-end but normal short stature.
"It started as a not-very-profitable drug given to maybe 1,000 people annually," says Norman Fost, pediatrician and bioethicist at the University of Wisconsin Medical School. "Now it's given to tens of thousands of people."
The theoretical fear has been that parents would start requesting medical treatment not just for the shortest kids on the normal continuum but also for healthy average-sized children, especially boys, who are referred for treatment twice as often as girls. If parents can decide to cosmetically straighten crooked teeth, or bob a child's prominent nose, why not buy the kid a couple of extra inches in height for what they believe may be a better shot at love and money?
Haddal went through a battery of tests to confirm that the children were in the normal range on growth charts and to eliminate underlying diseases that clearly can benefit from the injections: growth hormone deficiency, chronic renal insufficiency, Turner syndrome, Prader-Willi syndrome and children born small for gestational age, all of which can severely limit growth potential.
The two second-generation Americans had none of those conditions. "Clinically, they were perfectly fine," she says. Because the children fell between the 10% and 25% mark on growth charts, she declined the parents' entreaties to prescribe treatment. Still, when they walked out the door, Haddal could not be sure what they would do next. "I don't think that a board-certified pediatric endocrinologist would prescribe it in these cases. But God knows what may happen."
The worst-case scenario -- drugging kids daily with a synthetic hormone to try to make 6-footers out of them -- is probably rare. If it's happening at all, it is taking place on the unreported fringes of medicine.
Although the FDA-approved treatment is for the shortest of the short -- those in the lowest 1.2% for their age -- taller kids can be treated off label, though with every fraction of a percentage point beyond the FDA's guidelines it grows increasingly difficult to get insurance coverage. "I think everyone in my field has drawn a red line in the sand," says Dr. Henry Anhalt, director of pediatric endocrinology at St. Barnabas Medical Center in Livingston, N.J., and a member of the FDA advisory committee that approved growth hormone for idiopathic short stature. "I haven't seen any child above the fifth percentile that I'd write a prescription for."
Others in his specialty make similar statements, the declared line in the sand rarely going above the shortest 5% mark. At least, that's what they say publicly. "Among pediatric endocrinologists, it's the dirty little secret," Anhalt says. "They'll respond differently than when they're sitting in the office with a family crying their hearts out."
With that kind of emotional wiggle room, a determined parent could probably find someone willing to write a prescription for a child who is not particularly short.
There are good reasons for keeping height-obsessed parents of average height children at bay. The treatment, a daily injection, can be hard on a child. The synthetic hormone has rare but significant side effects, including curvature of the spine and pressure on the brain. And while it appears largely safe so far, no one knows if treated children will have problems such as diabetes, heart disease or cancer in middle age or older.
With only a three-year track record on treatment of children whose bodies make adequate growth hormone but still fail to grow normally, specialists advise families of risks, limited and unpredictable benefits and an array of unknowns. "Although we are unaware of long-term adverse events, like cancer or fertility issues, we don't have follow-up. It's a major hole in what we do, and we make that very clear to parents," Anhalt says.
Still, some children whose bodies don't produce growth hormone have been treated for 15 to 20 years with no apparent ill effects. So far, there's no reason to assume short children who have natural growth hormone will be harmed by the drug. "I don't go to bed at night worrying that I'm putting a child at risk," Anhalt says.