September 25, 2002
Two important studies were presented back to back. David Nolan's study was presented immediately after Michael Dubé's A5005s substudy of ACTG 384.
Using a different approach from the ACTG study (a longitudinal, non-randomized trial), this group from western Australia looked at what happened to the peripheral fat of treatment-naive patients who were started on a regimen containing either stavudine (d4T, Zerit) or zidovudine (AZT, Retrovir). The number of patients in this study was smaller than in the A5005s substudy. There were only 53 patients in Dr. Nolan's study, 27 of whom had received stavudine, and 26 zidovudine. Both groups of patients were comparable at baseline, with a slightly lower body mass index (BMI) for the group that received stavudine (remember, this was not a randomized trial). Patients were followed for two and a half years on average, and if they changed their medication, they were censored at that point.
Patients had three to six dual-energy x-ray absorptiometry (DEXA) scans during the follow up. With the longitudinal data captured, they were able to model fat loss over time for each group of patients. They were also able to create mathematical equations that would predict the rate of fat loss depending on the nucleoside (stavudine or zidovudine) that was selected to originally treat the patients.
The choice of stavudine or zidovudine was a strong predictor of the rate of fat loss in the extremities of these patients. Whether the patient was or was not on a PI- or an NNRTI-based regimen did not matter at all. Age and an AIDS diagnosis were also predictors of the fat loss.
The study has the beauty of longitudinal studies. Cross-sectional studies, no matter how well done or large they are, cannot tell us more of what they have told us already.
This study confirms A5005s, which proved that patients receiving stavudine lose peripheral fat faster than patients receiving zidovudine. Not a big surprise for anybody, but it is nice to see data that supports conventional wisdom.
|Please note: Knowledge about HIV changes rapidly. Note the date of this summary's publication, and before treating patients or employing any therapies described in these materials, verify all information independently. If you are a patient, please consult a doctor or other medical professional before acting on any of the information presented in this summary. For a complete listing of our most recent conference coverage, click here.|