INS and hyperinsulinism: Patients with FBG > 7mmol/L or OGTT ≥11.1mmol/L, and C-peptide level significantly higher than the normal value, and insulin secretion peak delayed after oral glucose were diagnosed as hyperinsulinemia and included in HINS (n=44), while those without hyperinsulinemia (n=48) were classified as NHINS based on oral glucose tolerance test (OGTT), glucagon-stimulating C-peptide test, and clinical manifestations.