Association of high-sensitive C-reactive protein with advanced stage β-cell dysfunction and insulin resistance in patients with type 2 diabetes mellitus

Background: Type 2 diabetes mellitus is associated with increased cardiovascular risk. One laboratory marker for cardiovascular risk assessment is high-sensitivity C-reactive protein (hsCRP). Methods: This cross-sectional study attempted to analyze the association of hsCRP levels with insulin resistance, beta-cell dysfunction and macrovascular disease in 4270 non-insulin-treated patients with type 2 diabetes [2146 male, 2124 female; mean age +/- SD, 63.9 +/- 11.1 years; body mass index (BMI) 30.1 +/- 5.5 kg/m(2); disease duration 5.4 +/- 5.6 years; hemoglobin A(1c) (HbA(1c)) 6.8 +/- 1.3% ]. It consisted of a single morning visit with collection of a fasting blood sample. Observational parameters included several clinical scores and laboratory biomarkers. Results: Stratification into cardiovascular risk groups according to hsCRP levels revealed that 934 patients had low risk (hsCRP < 1 mg/L), 1369 patients had intermediate risk (hsCRP 1-3 mg/L), 1352 patients had high risk (hsCRP > 3-10 mg/ L), and 610 patients had unspecific hsCRP elevation ( > 10 mg/ L). Increased hsCRP levels were associated with other indicators of diabetes-related cardiovascular risk (homeostatic model assessment, intact proinsulin, insulin, BMI, beta-cell dysfunction, all p < 0.001), but showed no correlation with disease duration or glucose control. The majority of the patients were treated with diet (34.1%; hsCRP levels 2.85 +/- 2.39 mg/L) or metformin monotherapy (21.1%; 2.95 +/- 2.50 mg/L hsCRP). The highest hsCRP levels were observed in patients treated with sulfonylurea (17.0%; 3.00 +/- 2.43 mg/ L). Conclusions: Our results indicate that hsCRP may be used as a cardiovascular risk marker in patients with type 2 diabetes mellitus and should be evaluated in further prospective studies.