FRIDAY, Nov. 7, 2003 (HealthDayNews) -- Growth hormone-deficient young adults require higher doses of replacement hormone than are currently prescribed and probably will need continued treatment for years.
That's the finding of a joint American-Canadian study in the November issue of the Journal of Clinical Endocrinology & Metabolism.
The study at 12 U.S. and five Canadian medical centers concludes that higher doses of growth hormone can protect these young adults from excessive and eventually debilitating reductions in bone density and from increased blood levels of harmful fats that could contribute to heart disease.
Previous research suggested growth hormone treatment also helped such people maintain healthy muscle mass and lower their levels of depression.
The study included 39 men and 25 women younger than age 35. Some received 12.5 micrograms per kilogram a day of growth hormone, others received 25 micrograms per kilogram a day, and a third group received a placebo.
The 25 microgram dose is about half the dose used in children.
Patients who received 12.5 micrograms of hormone showed better bone mineral density after two years compared to those taking the placebo. That improvement in bone mineral density was even greater and more sustained in those taking the 25 micrograms.
People in both groups taking the hormone showed decreased fat and increased lean mass after six months. But some of those improvement were later lost in the lower dose group.
"We did this randomized, double-blind, placebo-controlled trial to improve our understanding of what doses we should give to young adults who need treatment," lead researcher Dr. Louis Underwood, professor of pediatrics, University of North Carolina at Chapel Hill School of Medicine, says in a prepared statement.
"We believe our findings will change clinical practice in the United States and abroad," he says.
Currently, many doctors treat growth hormone-deficient children with hormone doses that reach their highest levels in late adolescence. That's when naturally secreted growth hormone reaches its peak in healthy children.
As these patients become adults, doctors often stop hormone treatment to determine whether it's still necessary. If it's determined that an adult still requires growth hormone treatment, it's often given at much lower doses. That's because adults require less of the hormone and don't tolerate it as well as children.
More information
Here's where you can learn more about adult growth hormone deficiency.
