INS and Insulin resistance: However, FPG showed moderate correlations with fasting plasma insulin (FPI, rS = 0.40, P < 0.001), proinsulin (rS = 0.38, P < 0.01), homeostasis model assessment as an index of insulin resistance (HOMA-IR, rS = 0.56, P < 0.001), and fasting plasma free fatty acids (FFA) (rS = 0.56, P < 0.001).