In order to assess the pattern of subcutaneous and visceral fat distribution and metabolic abnormalities among male patients treated with antiretrovirals, T. Saint-Marc and colleagues performed a cross sectional study of 154 men treated who received regimens with at least 2 antiretrovirals between August 1998 and February 1999. Seventy-two of the patients were determined to have normal fat distribution and metabolism; 22% of the patients showed lipoatrophy; 5.9% of subjects had pseudo-obesity; and 25.3% showed a mixture of the syndromes. Among patients with lipoatrophy and pseudo-obesity, those receiving d4T had different subcutaneous adipose tissue and triglyceride levels compared to those receiving AZT. Lipoatrophy was associated with d4T use as part of nucleoside reverse transcriptase inhibitor (NRTI) or protease inhibitor (PI) therapy, when compared with patients on AZT.

The authors further examined the effects of d4T discontinuation on metabolic abnormalities in patients on either NRTI therapy or PI therapy. Triglyceride and pyruvate levels decreased among patients who discontinued d4T in both groups, but no difference was observed in cholesterol or glucose levels compared to controls who remained on d4T. Patients who discontinued d4T showed increased body fat in the abdomen and mid-thigh subcutaneous fat region. Some patients, though, continued to worsen despite the discontinuation of d4T.

The authors believe that d4T use is associated with fat depletion in the abdominal and mid-thigh subcutaneous adipose tissue. They failed to report antiretroviral history or patient characteristics, though, which limits the ability to interpret the data. Additionally, the subjects were not randomized, which could introduce bias into the study.