Serum Cystatin C, Hs-CRP And Homocysteine As Biomarkers Of Diabetic Retinopathy In Patients With T2DM

Background:The aim of this study is to investigate the levels of serum Cystatin C, C-reactive protein and Homocysteine (Hcy) in diabetic retinopathy (DR) in patients with type 2 diabetes mellitus and elucidate their clinical prognostic significance.Methods:The levels of serum Cystatin C, C-reactive protein and Homocysteine (Hcy) were measured in 485 patients with type 2 diabetes by using a high sensitive latex-enhanced immunoturbidimetric method. Type 2 diabetes mellitus (T2DM) was diagnosed according to the 1999 World Health Organization criteria and 2012 American Diabetes Association standards. Venous blood was drawn from all patients after an overnight fast. All participants underwent fundus fluorescein angiography (FFA) carried out by ophthalmologists. Diabetes related macular degeneration (AMD) was diagnosed by FFA and optical coherence tomography (OCT). Patients were divided into four groups. Group 1 No Diabetic Retinopathy (NDR) and no AMD (n=60, Age 55.1±9.11); Group 2 Non-Proliferative Diabetic Retinopathy (NPDR) (n=180, Age 56.7±6.21); Group 3 Proliferative Diabetic Retinopathy (PDR) (n=160, Age 57.1± 10.07) and Group 4 AMD (n=85, exclude patients with NPDR or PDR, Age55.9±6.27).Results:Serum levels of Cys C, hs-CRP and Hcy were significantly different among the respective groups. The serum levels of Cys C in the PDR and AMD groups were higher than the control (p<0.01) and NPDR groups (p<0.01, p<0.05, respectively). The serum levels of hs-CRP in the PDR and AMD group was higher than the control (p<0.01) and NPDR group (p<0.05, p<0.01, respectively) and the serum levels of Hcy in the PDR and AMD group was higher than the control (p<0.01) and NPDR group (p<0.01).Conclusion:We propose that serum levels of cystatin C, C-reactive protein and Homocysteine (Hcy) play an important role in the clinical implications for patients with diabetic retinopathy (DR) in patients with type 2 diabetes mellitus.