Assessment of serum neopterin as an inflammatory and cardiovascular marker in type 1 and 2 diabetes complicated by diabetic foot syndrome: a comparative study

Abstract

Introduction. Neopterin is a byproduct of nerve trans­mitter coenzyme that is synthesized and released by macrophages and T-lymphocytes. It is a useful inflam­matory marker of diabetes progression, as its levels increase with the progression of the disease from prediabetes to type 2 diabetes (T2D). This study aimed to compare serum neopterin levels between type-1 and type-2 diabetes patients with diabetic foot syndrome (DFS), and assess the relation between serum neopterin levels and cardiometabolic risk factors. Materials and methods. This observational cross-sec­tional study was carried out in the Centre of Diabetes Mellitus in Erbil, Iraq from 1st January to 31st December 2016. A total of 30 healthy subjects and 140 patients with DFS [70 patients with type 1 diabetes (T1D) and 70 patients with T2D] were enrolled in the study. The main outcome measurements included anthropometric measurements, blood pressure, fasting serum glucose, glycated haemoglobin, lipid profile, neopterin and high sensitivity C-reactive protein (hs-CRP). Results. Serum neopterin levels of T2D patients were significantly (p < 0.001) higher than the corresponding levels of T1D patients (18.6 ± 2.1 nmol/L vs. 12.6 ± 1.3 nmol/L). The changes in the serum neopterin levels were related to cardiometabolic risk factors. In T1D, a significant positive correlation between serum levels of neopterin and diastolic blood pressure were ob­served, while in T2D the significant positive correlation was found between fasting serum triglyceride levels and neopterin levels. Serum levels of neopterin were insignificantly correlated with hs-CRP in T1D and T2D. Conclusions. In patients with DFS, serum neopterin lev­els are significantly higher in those with T2D compared with T1D patients. Neopterin levels are not related to the grading of DFS, but are invariably related to cardio­metabolic risk factors. (Clin Diabetol 2018; 7, 2: 91–96)