Impact of different INSTIs on BMI among people living with HIV who newly started ART in Shenzhen, China: a real-world data analysis

Background Integrase strand transfer inhibitor (INSTI)-based antiretroviral therapy (ART) might be associated with weight gain. The impact of different types of INSTIs has not been determined, particularly in combination with tenofovir disproxil fumarate (TDF) or tenofovir alafenamide fumarate (TAF). Methods We conducted a retrospective cohort study using real-world data from people living with HIV (PLWH) aged ≥18 years who newly started ART between 2019 and May 2023 in Shenzhen, China. We performed linear mixed models to assess whether BMI changes of PLWH differed significantly over time across ART classes, among INSTIs, and between TAF- and TDF-containing regimens. Results 5,102 PLWH who newly started ART (4,771 [93.5%] men; median age 31 [IQR 26–40]) were included in the study. Significant differences in BMI changes were observed among the treatment groups. Compared to PLWH who contemporaneously used nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens, people who used INSTI-based regimens 0-0.5 years after ART initiation experienced 1.27 greater BMI gain (95% CI 1.14 to 1.50), 0.5-1.5 years after ART initiation 0.18 greater BMI gain (95% CI 0.03 to 0.33). Compared to PLWH who newly started TDF+lamivudine [3TC]+DTG, TAF/emtricitabine [FTC]/EVG/c and TAF/FTC/BIC, those who used 3TC/DTG experienced greater BMI increases after ART initiation. Compared to people who contemporaneously used TAF-containing regimens, people who used TDF-containing regiments 0.5–1.5 years after ART initiation experienced 1.07 less BMI gain (−1.34 to −0.79). Conclusions Compared with NNRTIs, INSTIs were associated with an increase in BMI. The increase in BMI associated with 3TC/DTG is particularly prominent. Additionally, TDF showed potential weight-neutral or weight-suppressive effects.