Urinary C Peptide/ Creatinine Ratio Is Related to Insulin Resistance but Not Vascular Complications In Type 2 Diabetes

BACKGROUND. Insulin resistance (IR) is considered the main mechanism of type 2 diabetes (T2DM). Diabetic vascular complications (DVC) are main causes of morbidity and mortality. Urinary c-peptide to creatinine ratio (UCPCR) is a novel promising biomarker that may be of value in assessment of IR and DVC.

AIM. The present work aimed at studying the relation between UCPCR, IR and DVC in subjects with T2DM.

MATERIALS AND METHODS. This was a cross-sectional study performed on a group of subjects with T2DM. Insulin resistance was assessed by measuring homeostasis model assessment for insulin resistance (HOMA-IR). Laboratory investigations included glycemic parameters and renal functions. Human C-peptide ELISA kit was used to asses c-peptide level in a spot urine sample after processing.

RESULTS. The study included 90 subjects with T2DM. There was highly statistically significant positive correlations between UCPCR and HOMA-IR, FPG and HbA1c with P values of <0.001, 0.006 and 0.005 respectively. FPG, HbA1c, and UCPCR were the independent risk factors for IR in the univariate regression analysis. However, UCPCR was the only independent risk factor for IR in multivariate analysis (OR 16.431(1.401–192.706). UCPCR cut-off value (>0.19) nmol/mmol was able to differentiate significantly (p<0.001) between patients with IR and those without IR with good sensitivity, specificity and AUC (85.11%, 60.47% and 0.716 respectively).

CONCLUSION. In patients with T2DM, UCPCR could be used as a simple, noninvasive and available biomarker for IR. It also could be used as a marker of glycemic control. However, UCPCR is not related to DVC.

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