INS and type 2 diabetes mellitus: Although predictive factors for T2D remission after MS in Asian populations have already been published by other researchers, including young age, high BMI, short duration, lower levels of FPG and HbA1c, higher C-peptide concentration, and preoperative insulin use [18, 41–43], values of β-cell function, especially comprehensive indexes reflecting β-cell function in T2D remission, were lacking.