Study wrapper · #1313
Weight Regain Trajectories After Discontinuation of Semaglutide or Tirzepatide: A Reconstructed Aggregate-Data Bayesian Longitudinal Meta-Analysis.
Editor's note
A Bayesian re-analysis of aggregate timepoint data rather than individual participant records, which limits how finely predictors can be examined - the signals for initial weight loss magnitude and for behavioural support both had credible intervals crossing zero. The authors are explicit that anything past 52 weeks is a linear extrapolation, so the 15-month return-to-baseline figure is a model output, not an observation. Even with those caveats, the direction and speed of regain are consistent with what individual discontinuation trials have reported.
Plain-language abstract
This analysis pooled published data from six studies and 1,776 participants to model what happens to body weight after people stop semaglutide or tirzepatide. Weight loss at the point of stopping averaged about 15 kg, followed by regain of roughly 1 kg per month. On that trajectory, half the lost weight would come back by about 7.5 months and the starting weight by about 15 months. Tirzepatide looked numerically faster to regain than semaglutide, but the difference did not hold up after adjustment.