Switching to INSTI-Based ART Affects Weight but not Cholesterol

Switching to an integrase strand transfer inhibitor (INSTI), as part of antiretroviral therapy (ART), induces significant weight gain but does not affect cholesterol or hemoglobin A1C levels, according to new data presented at IDWeek 2019.

To conduct their study, the researchers recruited all patients with virogically suppressed HIV who switched from a non-INSTI to INSTI-based antiretroviral therapy from May 2015 to December 2017at a single academic medical center.

Patients included in the study were adults taking non-INSTI–based antiretroviral therapy for at least 1 year before switching to an INSTI-based regimen.

The researchers reviewed participants’ changes in weight, body mass index (BMI), cholesterol, and hemoglobin A1C from the year prior to the switch and 18 months after the switch.

In all, 90 patients were included in the study. After switching to INSTI-based ART, participants experienced significant increases in weight and BMI but not cholesterol or hemoglobin A1C levels.

Participants gained an average 2.2 kg after switching, with 26% gaining 4.5 kg or more. Those who switched from non-nucleoside reverse transcriptase inhibitors had numerically greater mean increases in weight compared with those who switched from protease inhibitors.  

Gender, race, and pre-switch BMI, as well as pre-switch and post-switch ART components, were not predictors for weight gain. However, increasing age was protective against weight gain.

“Weight gain in patients switching to INSTI-based ART observed in this analysis did not correspond to changes in cholesterol or glycemic control,” the researchers concluded. “Some patients receiving INSTIs in this sample gained substantial amounts of weight. The mechanisms and risk factors for substantial weight gain require further study.”

—Amanda Balbi


Zimmerman M, DeSimone J, Schafer JJ. Exploring the prevalence and characteristics of weight gain and other metabolic changes in patients with HIV infection switching to integrase inhibitor containing ART. Paper presented at: IDWeek 2019; October 2-6, 2019: Washington, DC.