Fat Problems Challenge HIV Treatment
"We feel that as the years go by we are going to see more and more [heart] disease," Kumar says. "We are looking at patients to see what are their risks of heart disease. And then we more aggressively are using [cholesterol]-lowering agents. All of us first try exercise and diet, but in the majority of patients it doesn't work. Up to 50% will need [cholesterol]-lowering agents. This is much more difficult than in non-HIV patients because these drugs have important interactions with anti-HIV drugs."
People don't just take one anti-HIV drug. They take combinations, commonly known as drug cocktails. This works great against the AIDS virus, but it's made it hard to tell which drugs cause which long-term side effects. Now some trends are beginning to appear.
The first big change came two years ago. Doctors realized that they could put off starting the drugs -- and their side effects -- until a patient's HIV disease weakened the immune system to the point of AIDS. New studies, some presented this week at the annual Retrovirus conference, now show that some AIDS drugs are linked to specific side effects:
- Each class of drugs tends to cause the same kinds of side effects -- but to different degrees.
- The nukes (nucleoside RT inhibitors or NRTIs). These drugs include Retrovir, Combivir, Zerit, Videx, and Ziagen. They are linked to nervous-system problems, muscle and liver problems, and likely to fat wasting.
- The protease inhibitors (PIs). These drugs include Fortovase, Norvir, Crixivan, Viracept, Agenerase, and Kaletra. They are linked to problems with fat metabolism. They also seem to be linked to loss of bone and osteoporosis.
- The non-nukes (non-nucleoside RT inhibitor or NNRTIs). These drugs include Viramune, Rescriptor, and Sustiva. Individual drugs of this class differ in their side effects. Viramune seems not to affect fat metabolism. Sustiva does, but not as much as the PIs.
New studies presented at the Retrovirus conference show that:
- The combination of Combivir and Ziagen causes fewer fat problems than combinations that contain PIs.
- Switching from Zerit to Ziagen or Retrovir improves fat wasting.
- Combination treatment with nukes and non-nukes seems less likely to cause fat problems than the combination of nukes and PIs.
- Switching from a PI-based combination to a combination containing Ziagen, Sustiva, or Viramune reduces fat problems.
- Neither Glucophage nor Lopid seem to help patients with HIV-related lipodystrophy syndrome.
- According to an article in the current issue of Nutrition, the statin-containing dietary supplement called Cholestin helps with HIV-related fat problems.