INS and type 2 diabetes mellitus: After an adjustment of the potential factors, including age, gender, duration of T2DM, BMI, smoking, hypertension, ARB/ACEI medication, insulin medication, metformin medication, HbA1c, TG, and TC, the ORs for DKD in FT3-Q2, FT3-Q3, and FT3-Q4 were 0.605 (95%CI: (0.382–0.957), 0.516 (95%CI: 0.317–0.838), 0.471 (95%CI: 0.280–0.792) (P = 0.032, P = 0.008, P = 0.005).