Weight Gain in HIV Adults Receiving Antiretroviral Treatment: Current Knowledge and Future Perspectives

Body weight is impacted by several individual host and environmental factors. In a person living with HIV (PLWH), weight is also influenced by the disease stage. Wasting syndrome is derived from disease progression, and it can be reversed by the effective use of highly active antiretroviral therapy (HAART). Body weight alterations have been studied and compared in several clinical ART trials, and they differ according to antiviral regimens. The newer integrase strand transfer inhibitors (INSTIs), such as bictegravir and dolutegravir, especially when co-administered with tenofovir alafenamide fumarate (TAF), seem to lead to greater weight increases compared to regimens that include tenofovir disoproxil fumarate (TDF), which seem to have an attenuating effect on weight gain. Nevertheless, despite the established association between INSTI and TAF and the negative impact on weight, more recent data suggest a more cautious approach when HAART treatment decisions are taken. In this manuscript, we review weight changes among PLWH receiving HAART and the relevant underlying pathogenic mechanisms described in recent literature. We try to provide a more critical appraisal of the available data and to underline the challenges in assessing the role of HAART in weight changes in both ART initiation and setting switching.