A pilot study using metformin, a drug used to treat type 2 diabetes, indicates that the medication may be useful in treating HIV lipodsytrophy, a disorder of fat metabolism that occurs in people with AIDS, particularly those taking combination antiretroviral treatment. The trial in a group of patients with HIV and lipodystrophy, conducted by researchers at the Massachusetts General Hospital (MGH), appears in the July 26 Journal of the American Medical Association.
HIV lipodystrophy is a new syndrome affecting a large percentage of HIV-infected patients. The condition is characterized by abnormal fat distribution on the body -- excess fat in the abdomen with loss of fat in the extremities and face -- combined with metabolic changes such as insulin resistance and elevated levels of cholesterol and triglycerides. Patients with HIV lipodystrophy may be at increased risk for cardiovascular disease, and there currently is no treatment for the condition.
In this three-month, double-blinded study, the MGH team examined the effects of the insulin-sensitizing agent metformin on several metabolic and cardiovascular measurements. The 26 participants were randomized to receive twice daily doses of either 500 milligrams of metformin or a placebo. Among the 14 patient taking metformin, insulin levels dropped by an average of 20 percent (elevated insulin levels are an indication of insulin resistance), while the control group members showed no significant changes. Those receiving the drug also showed significant reductions in weight, blood pressure and abdominal fat. There were additional indications of possible benefits in blood sugar and lipid (triglyceride) levels.
"This was a pilot study using a novel agent to treat the HIV lipodystrophy syndrome," says Steven Grinspoon, MD, of the MGH Neuroendocrine Unit, the paper's senior author. "The results are promising, and the treatment was very well tolerated, with no serious side effects reported. However, longer-term studies with larger groups of patients are needed to better understand which patients might benefit from metformin, what the long-term cardiovascular benefits might be, and whether other measures - such as dietary change - would also be helpful." Grinspoon adds that the study's encouraging results need further investigation before metformin can be routinely recommended for treatment of HIV lipodystrophy.
Grinspoon's co-authors are first author Colleen Hadigan, MD, and Colleen Corcoran, NP, of the MGH Neuroendocrine Unit; Nesli Basgoz, MD, and Benjamin Davis, MD, of the MGH Infectious Disease Unit; and Paul Sax, MD, of the Division of Infectious Diseases at Brigham and Women's Hospital. The study was supported by grants from the National Institutes of Health.
Journal
JAMA