Objective:To investigate the effects of dyslipidemia on early insulin secretion and insulin resistance in patients with type 2 diabetes mellitus(T2DM).Methods:93 newly diagnosed T2DM patients without lipid-lowering and anti-hyperglycemia therapies were divided into 3 groups by plasma lipids levels:normal lipids(group B)

single high triglycerides(group C)

and high triglycerides and high total cholesterol with or without low HDL-cholesterol or high LDL-cholesterol(group D).20 non-diabetic normal lipids subjects were healthy control group(group A).Early insulin secretion indexes(ΔI30/ΔG30)and insulin resistance indexes(HOMA-IR)taken from the oral glucose tolerance test were measured and analyzed.Results:Compared with healthy control subjects(group A)

patients with T2DM(group B

C and D)had a significantly lower ΔI30/ΔG30(P=0.0000

<0.05 and <0.05)and HOMA-IR(all P<0.05).In contrast with group B

group C and D had a significantly lower ΔI30/ΔG30(both P<0.05)

and

group D had a significantly higher HOMA-IR(P=0.0027)in T2DM groups.But no significant differences of the ΔI30/ΔG30 between group C and D(P=0.2509)

and the HOMA-IR between group B and C(P=0.1841)were observed.Conclusion:Our study supports the notion that high triglycerides reduce early insulin secretion function and cholesterol abnormalities increase insulin resistance in T2DM.