Among people on fully suppressive antiretroviral (ARV) treatment for HIV, the harmful chronic inflammation, or ongoing activation of the immune system, they experience may have a synergistic relationship with weight gain.

Presenting their findings at the 2019 Conference on Retroviruses and Opportunistic (CROI) Infections in Seattle, researchers drew a sample of 340 HIV-positive people from a pair of AIDS Clinical Trials Group studies of individuals starting ARV treatment for the first time. They deliberately chose people who fell into one of two categories: those who maintained their body mass index (BMI) within half a point above or below their starting BMI after 96 weeks of ARVs and those who gained weight after starting ARVs and experienced a 2.6- to 6.4-point increase in BMI after 96 weeks of ARVs.

Upon starting HIV treatment, the cohort members had a median age of 42 years old, a median CD4 count of 273 and a median viral load of 50,000. Forty-nine percent of the cohort members were women, 33 percent were white, 42 percent were Black and 24 percent were Latino. The average baseline BMI was in the normal range, between 18.5 to 24.9, and none of the cohort members had a BMI below 18.5. Those who gained weight gained about six to 14 pounds.

The investigators analyzed samples taken from the cohort members when they started ARVs and after 96 weeks of treatment, looking for a series of proteins that are indicators of immune activation, or inflammation.

Compared with the women who did not gain weight, those who did were more likely to have high immune activation levels at week 96. Among all the cohort members, those who had high levels of immune activation when they started ARVs were more likely to experience weight gain.

In other words, immune activation and weight gain may drive each other, in particular among women. Strategies that help people with HIV control their weight and also those that reduce immune activation could help alleviate the burden of even well-treated virus on the body.

To read a press release about the study, click here.

To read the conference abstract, click here.