It’s easy to weigh down medical information in a lot of mumbo-jumbo, but HIV specialist Dr. Joel Gallant, of Johns Hopkins University School of Medicine, has a knack for putting things in short, simple words. Without listing all the studies involved, he explained which HIV drugs cause problems and which ones don’t in a lipoatrophy chat last November for TheBody.com. Lipoatrophy is thinning of the face, arms, and legs, which can be caused by HIV medications. Following is a shortened version of Gallant’s answers to the people who attended the chat. Most of the generic drug names have been removed.—Enid Vázquez

The best thing you can do is to take medications that don’t cause lipoatrophy, which is easy enough to do if you’re starting therapy for the first time, without any drug resistance. I have lots of patients with lipoatrophy, but they’re all people who’ve been on therapy since back in the 20th century. I’m not seeing new development of lipoatrophy anymore, because we now have better treatment options. Don’t let the fear of lipoatrophy dissuade you from taking antiretroviral therapy if you need it!

If you have no drug resistance and can take anything you want, then combinations that are unlikely to cause body shape changes would be either Truvada or Epzicom plus either Sustiva, Viramune, or Reyataz (preferably boosted with Norvir). However, you’re unlikely to get lipoatrophy with any protease inhibitor, as long as you’re using Truvada or Epzicom, as the association between fat accumulation and protease inhibitors is not as direct as the association between lipoatrophy and thymidine analogs (like AZT [brand name: Retrovir; also known as zidovudine] and d4T [brand name: Zerit; also known as stavudine]).

The drugs that are known to cause lipoatrophy are [Zerit], AZT (whether it is in the form of Retrovir, Combivir, or Trizivir), and possibly also [Videx]. Drugs that are not believed to cause it are [Epivir], [Emtriva], tenofovir (whether it is in the form of Viread or Truvada), and abacavir (whether it is in the form of Ziagen or Epzicom). Because you’re [the person asking the question] on Combivir, you could still be losing fat due to AZT. If your resistance pattern (or lack of it) will allow you to switch to Truvada or Epzicom, that could help a lot.

We have head-to-head trials that show a clear difference. For example, after three years, people on [Zerit] got lipoatrophy, while those on [Viread] didn’t. And we also know that switching from [Zerit] or AZT to either [Viread] or [Ziagen] allows fat to return, which makes it pretty unlikely that either of those drugs causes lipoatrophy.

If you’ve switched from Zerit to either Viread or Ziagen (rather than to AZT), then your fat should start coming back, but it can take a long time, and there’s no guarantee that it will be completely restored. If you’ve got the money, Sculptra injections seem to be the most effective way to deal with facial fat loss.

It may be the case that you regain fat at about the rate that you lost it.

It sounds like you [the person asking the question] need to get off the AZT, if you can do so without jeopardizing your virologic [viral load] response. Everyone knows now that [Zerit] causes lipoatrophy, but we often forget that AZT does it too, but just at a slower rate. Getting off AZT won’t make everything all right again, but it could halt further loss of fat, and may allow fat to return… slowly. You’re now on drugs that are less likely to cause fat accumulation [Viread, Combivir, and Viramune], but that doesn’t mean that what happened to you on previous regimens will go away.

With fat accumulation, the things to do are to (1) eat a low-fat diet; (2) exercise regularly, especially with aerobic exercise; (3) keep your lipids, and especially triglycerides, under control; and (4) treat insulin resistance, if you have it. Insulin resistance is diagnosed by fasting insulin levels and/or glucose tolerance tests.

[Question: Is eating too much sugar a contributing factor to lipo?] It could definitely contribute to fat accumulation, but probably not to lipoatrophy. If you have fat accumulation, you need to avoid insulin resistance and hyperglycemia [high blood sugar] if possible.

The link between antiretrovirals and fat accumulation isn’t as strong as the link with lipoatrophy, but drugs that cause high triglycerides and insulin resistance may be the ones that cause the problem the most. Protease inhibitors cause those problems, but Reyataz seems to be an exception, so the regimen they’re recommending [Reyataz/Trizivir] is probably pretty safe from a fat accumulation perspective.

We don’t have a lot of information on Videx, because for many years it was usually combined with other drugs that cause lipoatrophy (AZT and d4T). However, there is reason to believe that Videx could cause lipoatrophy. In addition, there are several concerns about combining Viread and Videx, including CD4 decline and easy selection of resistance, especially when combined with Viramune or Sustiva. So you have several reasons to discuss this with your doctor.

We know that lipoatrophy is reversible if you stop the drugs that cause it. The reversibility is slow and may not be complete, but that’s better than nothing.

Editor’s Note: TheBody.com has a lipodystrophy section, www.thebody.com/lipo/index.html.