ABSTRACT
·AIM: To evaluate correlation of cystatin-C (Cys-C) with severity of diabetic retinopathy (DR) and acute phase reactants, including erythrocyte sedimentation rate (ESR) and high-sensitivity C-reactive protein(hs-CRP). ·METHODS: All diabetic patients who were referred for diabetic retinopathy (DR) screening during 1mo were enrolled. Demographic data were recorded. All patients have undergone full ophthalmic exam. At the same day, all patients were tested for hemoglobin A1c (HbA1c), ESR,hs-CRP,and Cys-C serum levels. · RESULTS: Sixty seven diabetics were enrolled, including 19 (28.3%) without retinopathy, 22 (32.8%) non - proliferative retinopathy, and 26 ( 38. 8%) proliferative retinopathy patients. The mean age, sex distribution, mean duration of diabetes, prevalence of hypertension and dyslipidemia, smoking status and HbA1c levels were not significantly different among the three groups. The mean levels of Cys - C increase significantly as retinopathy progress [1.1 ± 0. 48; 1. 22 ± 0.38;1.71 ± 0.92 (P=0.007), respectively]. In multiple regression analysis, just Cys - C was significantly associated with severity of DR (P=0.025). ·CONCLUSIONS: This study revealed that serum levels of Cys-C increase while DR progress independently of acute phase reactants. Therefore, it could be used as an associated marker by primary care physicians to distinguish patients at higher risk of severe DR. Larger randomized studies are warranted to confirm findings. Reviewing physiological role of the Cys-C, we proposed that the Cys-C may be a protective response to catalytic stress rather than being a pathogenic factor in microangiopathies.
ABSTRACT
PURPOSE: The purpose of this study was to evaluate whether any stage of diabetic retinopathy (DR) is associated with levels of plasma erythropoietin and other plasma parameters. METHODS: It was examined a representative sample of 180 type 2 diabetes patients aged 40 to 79 years. Ophthalmic examination including a funduscopic examination, performed by an experienced ophthalmologist and the retinal finding were classified according to the grading system for diabetic retinopathy of ETDRS (Early Treatment Diabetic Retinopathy Study). It was measured the levels of plasma erythropoietin, cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, fasting blood glucose and hemoglobin A1C (HbA1C) in 88 DR patients and 92 controls without DR. Risk factors correlated with DR were compared between groups. RESULTS: The study group of 180 patients included 72 males and 108 females. The mean age of the patients with and without DR was 57.36 ± 8.87 years and 55.33 ± 8.28 years, respectively. Of the 88 patients with DR, only 9 (10%) had proliferative DR and the rest suffered from non-proliferative DR. The mean plasma levels of erythropoietin in proliferative DR group showed a significant difference in comparison to other groups. The mean plasma levels of cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, and fasting blood glucose were not significantly different in the three groups except for HbA1C. The absolute relative risk (ARR) also showed that erythropoietin was an increasing risk for proliferative DR (ARR, 1.17; 95% confidence interval, 1.060 to 1.420; odds ratio,1.060). CONCLUSIONS: Of the factors studied, erythropoietin level showed significant increase in proliferative DR group. The stepwise raised in mean plasma erythropoietin level which demonstrates significant correlation with proliferative DR versus remaining two groups, will be an indication of its role in proliferative DR.