IMPORTANCE: Suboptimal weight loss affects 20%-35% of patients after metabolic bariatric surgery (MBS). Randomised evidence on glucagon-like peptide-1 receptor agonist (GLP-1 RA) pharmacotherapy in this population is limited to small, single-center Western trials. No data exist from Chinese populations.
OBJECTIVE: To emulate a target trial comparing GLP-1 RA initiation with standard care among suboptimal responders to MBS in a Chinese multicenter cohort.
DESIGN, SETTING, AND PARTICIPANTS: Target trial emulation using electronic health record (EHR) data from two Tertiary A teaching hospitals in China (March 2019 to June 2024). Eligible adults aged 18-65 years had undergone sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB), were 12-36 months post-surgery with body mass index (BMI) ≥ 28 kg/mand suboptimal weight loss. The clone-censor-weight approach handled the 30-day grace period. 1:5 propensity score matching yielded 624 patients (104 GLP-1 RA, 520 standard care). 2
INTERVENTIONS: Strategy A: GLP-1 RA initiated within 30 days. Strategy B: standard post-MBS care without GLP-1 RA.
MAIN OUTCOME: Percentage of total body weight loss (%TBWL) at 12 months.
RESULTS: Mean age was 36.4 years; 66% were female; mean BMI was 33.7 kg/m. At 12 months, mean %TBWL was 7.5% in the GLP-1 RA group versus 1.2% in the standard care group (difference, 6.28 percentage points; 95% CI, 5.50 to 7.07; p < 0.001). The ≥ 5% TBWL responder rate was 75% versus 7%. The per-protocol effect was 6.44 percentage points (95% CI, 5.65 to 7.23). Results were consistent across surgery types, BMI thresholds, diabetes status, and all sensitivity analyses. 2
CONCLUSIONS AND RELEVANCE: In this target trial emulation, GLP-1 RA initiation was associated with clinically meaningful weight loss among Chinese suboptimal responders to MBS. These findings extend Western randomised trial evidence to a Chinese multicenter real-world setting and support the integration of GLP-1 RA pharmacotherapy into post-bariatric care pathways in China.
