Is serum C-reactive protein concentration correlated with HbA1c and insulin resistance in Type 2 diabetic men with or without coronary heart disease?

Abstract

Background and aims: C-reactive protein (CRP) is an inflammatory marker that predicts coronary heart disease (CHD) risk. Diabetes mellitus (DM) counts as a CHD risk equivalent. We aimed to compare serum high sensitivity CRP (hs-CRP) levels in Type 2 diabetic (T2DM) men without CHD, non-diabetic CHD patients and T2DM patients with CHD.

Subjects and methods: Four groups were formed; Group 1 [DM(+), CHD(-), no.=25], Group 2 [DM(-), CHD(+) no.=25], Group 3 [DM(+), CHD(+), no.=25], and Group 4 (controls, no.=30). Serum hs-CRP, insulin, glucose, total, HDL-, LDL- and VLDL-cholesterol, triglyceride levels and homeostasis model assessment for insulin resistance (HOMA-IR) index were determined.

Results: Mean hs-CRP level of Group 1 (0.6+/-0.29) was not different statistically from Group 2 (1.44+/-0.97). Mean hs-CRP levels were higher in men with CHD, whether they were diabetic (Group 3; 3.83+/-2.01 mg/dl) or non-diabetic (Group 4), than in control subjects (0.16+/-0.15; p=0.0001 and p<0.004, respectively). Mean hs-CRP level of Group 3 was also higher than Group 2 (p=0.0001). There was a positive correlation between serum hs-CRP and glycated hemoglobin (HbA1c; r=0.277, p<0.01), fasting insulin (r=0.336, p<0.02) and HOMA-IR (r=0.348, p<0.02) in T2DM men with or without CHD.

Conclusions: T2DM men without CHD had similar CRP levels with non-diabetic CHD patients, whereas CRP levels of T2DM men with CHD were higher than non-diabetic men with CHD. Because of a positive correlation between serum hs-CRP and HbA1c, fasting insulin and HOMA-IR, inflammation, insulin resistance and hyperglycemia jointly contribute to the cardiovascular risk in T2DM men.