Low doses of human growth hormone can reverse some of the abnormal fat distribution caused by HIV therapy, lowering the risk of cardiovascular disease, but the treatment may produce an unnecessary risk for those who have early stages of diabetes, researchers said Sunday.
The hormone produced good results but would have to be used carefully to avoid inducing diabetes, said Dr. Steven Grinspoon of the Harvard Medical School, lead author of the paper.
He presented the results, which will be published this week in the Journal of the American Medical Assn., at the International AIDS Conference in Mexico City.
About 40% of males and 16% of females who take cocktails of anti-AIDS drugs for their HIV infections develop fat deposits in the stomach, neck and cheeks.
Called visceral fat, it is associated with higher levels of cholesterol and triglycerides and increases the risk of heart attacks and stroke.
Such patients typically have abnormally low levels of growth hormone and researchers had hoped that replacing it with genetically engineered human growth hormone -- the same drug used to treat below-normal growth rates and that is abused in athletics -- might reverse the effects.
But previous studies using higher levels of the hormone produced unacceptable side effects, including tissue swelling and pain in the joints.
Grinspoon and his colleagues studied 56 HIV-positive patients who had deposits of fat in their stomachs and low blood levels of the hormone.
Half were given daily doses of about 0.33 milligrams of the hormone, well below the 2 to 4 milligrams used in previous studies.
Half the subjects were given a placebo.
Over the 18 months of the study, stomach fat dropped by 8.5% in the patients receiving the hormone, compared with 1.6% in those getting a placebo. The team did not study their cardiovascular risk.
Tests showed some elevation of blood sugar in those receiving the hormone, particularly those who had abnormal glucose tolerance tests at the beginning of the trial.
Grinspoon said that future clinical trials should include a diabetes drug, such as metformin, to minimize side effects.
Another study in the special AIDS-themed issue of JAMA found that rifampicin, a drug commonly used to treat tuberculosis, can interfere with the treatment of AIDS. The finding was important because about a third of the HIV-positive people in the world also have tuberculosis.
