Guides

Weight increases on ART

Changes in body weight

HIV researchers have spent a lot of time looking at whether changes in weight is a side effect of some HIV drugs. This is especially over the last few years,

One question is whether weight gain is a side effect of integrase inhibitors (INSTIs), especially dolutegravir and bictegravir. However, several other drugs might also increase or decrease your weight. For example, both efavirenz and TAF are now linked to lower weight.

Average weight changes are usually small, so this is not a good reason to decide on which meds to use. INSTIs are still the best meds in terms of reducing viral load and having few side effects. They are still the first choice in all treatment guidelines.

INSTIs are highly effective, easy to take and have a low risk of drug resistance.

Instead, record your weight and measure your waist before you start. Make sure your doctor records these results and checks them at every visit.

Both are likely to increase a little over the first six months, but only by a little.

The earlier you know about any significant weight changes the easier it will be to manage. This will usually involve either diet and exercise or to change treatment.

Also, changing the INSTI to either doravirine or boosted darunavir did not reduce weight over six months in two small studies.

Several other things are important.

Firstly, nearly everyone puts on some weight in the first six months of treatment. This is especially if your viral load was high. This is healthy, because you body is no longer using energy to fight HIV.

Weight tends to increase more in people who start with a low weight, and might even drop a little if you start with a high weight.

In 2019, the ADVANCE study in South Africa, reported higher increases in weight with dolutegravir compared to efavirenz. The average of 6 kg after one year though was still much higher than expected. It was highest if people also used TAF instead of TDF. The increases were higher in women compared to men.

The weight increases continued in year two and three of the study. Very few people changed treatment though. However, this also increased the risk of serious weight-related complications, such as heart disease and diabetes.

Secondly, the caution is mainly for African women, who had the most significant weight increases. One reason that weight changes were not reported earlier is because most drug research is carried out in largely white male populations.

These results might also be specific to South Africa. This is because a similar study did not find such large wright increases in African women in Uganda. Also, other studies reported similar weight changes to those in ADVANCE in the general population in South Africa.

The ADVANCE study showed the importance of studies enrolling a wide range of people who will use these drugs globally.

Thirdly, research is still ongoing to explain the findings in the ADVANCE study. This needs to allows for weight increases in the general population and also as we age (as we become less active). We also need to find out how to manage or reverse any weight gain.

The findings are likely to be true though, at least in South Africa, because ADVANCE was a large randomised study that also compared dolutegravir to efavirenz and compared TAF to the earlier version of tenofovir (TD). Although people using TAF had increased weight compared to TD, this is because TD slightly reduces weight.

Weight changes on ART and how to lose weight successfully.

Other body changes

Other than weight, other body changes were only linked to the early HIV treatment used about 20 years ago.

This included fat loss (to the face, arms and legs) and fat gain (to the stomach, breasts and at the back of the neck).

These side effects are not side effects with current HIV drugs.

Metabolic changes

Metabolic changes can occur with many HIV drugs and combinations, but can also be caused by lifestyle factors including poor diet and lack of exercise.

For example:

  • Changes in blood lipids (fats) like cholesterol and triglyceride levels.
  • Changes in blood glucose (sugar) – an early signs of diabetes.

Routine monitoring by your HIV clinic, with blood or urine tests, look for these possible side effects.

Diet, exercise, changing treatment or using lipid-lowering drugs can all help.

If you are worried, your doctor should take your concerns seriously and act on them.

Last updated: 1 September 2024.