INS and diabetes mellitus: Our study found that, in the FDRs of T2DM, hyperproinsulinemia (defined by fasting proinsulin ≥9.8 pmol/L) has been identified as 20% in NGT, 45% in pre-DM group, and more than 2/3 in T2DM group, while true hyperinsulinemia was 27% in pre-DM group and only 17% in T2DM group.