Relationship between serum level of lipoprotein (a) and central macular thickness in diabetic patients

Abstract

Background and aim Diabetic retinopathy and maculopathy are major tragedies in ophthalmology. Lipoprotein (Lp) (a) is a pro-atherogenic and a pro-thrombotic risk factor. It has an antifibrinolytic effect with increasing risk of clotting and blood vessel occlusion. Elevated Lp (a) concentrations can also damage the microcirculation by its oxidative effect. The aim of this study was to investigate the relationship between serum level of Lp (a) and the development of maculopathy in diabetic patients by measuring the central macular thickness (CMT) using optical coherence tomography.Patients and methods This case–control study included one case group of 40 eyes of 20 diabetic patients and one control group of 40 eyes of 20 nondiabetic age-matched and sex-matched patients. All participants were subjected to full ophthalmological examination, including best-corrected visual acuity testing, BMI calculation, glycosylated hemoglobin (HbA1c), serum Lp (a), and CMT measurement by three-dimensional optical coherence tomography.Results There was no significant difference between the two groups regarding age or sex. Cases group had significantly higher BMI, HbA1c, Lp (a), and CMT than the control group (P<0.001 for all). In addition, cases had significantly lower best-corrected visual acuity than the controls (P<0.001). A significant positive correlation was found between CMT (μm) and each of HbA1c, Lp (a), and BMI (P<0.001, P<0.001, and P=0.002, respectively). Lp (a) level of 11.34 ng/ml or more was found to have a 95% sensitivity, 95% specificity, and 95% overall accuracy in predicting central macular edema (CME). On univariate logistic regression analysis, both of the BMI and Lp (a) were independent significant predictors for CME (P<0.001 and P=0.05, respectively), with odds ratio of 1.569 and 14.482, respectively.Conclusion Lp (a) was significantly correlated with CMT. It had an excellent sensitivity and specificity in predicting CME and can be used as a potential marker for its detection.