Abstract: [Abstract] Objective To explore one-year change trajectory in body mass index after sleeve gastrectomy among severe obesity patients,and then identify predictive factors of different trajectories.Methods 241 patients with sleeve gastrectomy were included.The data of body mass index at baseline,1,3,6,12 months after sleeve gastrectomy were used to construct the growth mixed model.And the baseline data were compared according to various trajectories.Results Three different trajectories were finally obtained,named as “Routine weight loss trajectory”(29.5%),“Rapid weight loss trajectory” (27.0%) and “Slow weight loss trajectory” (43.6%),respectively.There were significant differences in age,gender and marital status between different trajectories.Further paired compariso n showed that gender and marital status had significant effect on the difference between trajectories.Conclusion BMI decreased slowly in 43.6% patients after sleeve gastrectomy.Female and married status were important predictors of the unsatisfactory one-year weight loss trajectory after sleeve gastrectomy.Younger age also helps predict postoperative weight loss.

Key words: sleeve gastrectomy, body mass index, trajectories, predictive factors