The Role of Lipoprotein (a) and Dyslipidemia in Diabetic Retinopathy in a Sample of Syrian Patients with Type 2 Diabetes Mellitus

Objective: Diabetic retinopathy (DR) is a leading cause of vision loss in the working-age group. Detecting DR-related risk factors is the best early prevention strategy. The purpose of this study was to investigate the association between lipoprotein (a) [)Lp(a)] and DR occurrence. Additionally, the study aimed to determine the relationship between dyslipidemia and DR incidence in a sample of Syrian patients with type 2 diabetes mellitus (T2DM). Methods: One hundred and twenty-two participants were included in this case–control study. Thirty-one participants were in the control group, 61 were in the T2DM with DR (DM and DR) case group, and 30 were in the T2DM without DR group. Fundus examination was performed to assess the existence and degree of retinopathy. Lp(a), lipid profile component, fasting glucose, glycated hemoglobin (HbA1c) were measured. Results: Lp(a), total cholesterol (TC), triacylglycerol (TAG), low-density lipoprotein cholesterol (LDL-C), and nonhigh-density lipoprotein cholesterol (non-HDL-C) were significantly higher in the DM and DR case group compared to the other groups. HDL-C was the lowest in the DM and DR group (P < 0.001). Lp(a) exhibited significant positive correlations with body mass index, blood pressure, TAG, TC, LDL-C, non-HDL-C, and fasting plasma glucose; however, it had a negative correlation with HDL-C. The odds ratio of non-HDL/HDL was highest, followed by non-HDL after adjusting for Lp(a). The best cut-off point of Lp(a) for predicting DR assessed by receiver operating characteristic curve was 36.1 mg/dL (area under curve 0.772). Conclusions: Our findings suggest that Lp(a) and lipid profile components were risk factors for DR incidence in T2DM patients. Non-HDL-C/HDL-C ratio was the best lipid predictor.