Study of the association of lipocalin-1 in tears with the progression of diabetic retinopathy: Cross-sectional comparative study

Abstract Context: Biomarkers are measurable indicators of a biological process or condition that can aid in the diagnosis and management of diseases. We have explored the role of Lipocalin in predicting the progression of DR. Aims: The aim of this study was to compare the levels of lipocalin-1 (LCN1) in tears of patients with established diabetic retinopathy (DR) with patients without DR and to evaluate the clinical application of LCN1 as a biomarker which can predict the progression of DR. Settings and Design: This cross-sectional comparative study was conducted in the outpatient setting of the department of ophthalmology and the department of biochemistry. Subjects and Methods: The tear samples obtained from the patients with no DR, nonproliferative DR (NPDR), and PDR were analyzed using enzyme-linked immunosorbent assay, and levels of LCN1 were compared among the three groups. Statistical Analysis Used: All data were expressed as mean ± standard deviation, and all significant differences were analyzed using the Chi-square test for qualitative data and one-way analysis of variance for quantitative data with the SPSS 20.0 statistical software data analysis (SPSS, Chicago, IL, USA) to compare the means between the three groups. Results: Levels of LCN1 were significantly reduced in patients with DR when compared to levels in patients with no DR. The expression levels might be useful as a diagnostic and prognostic biomarker of DR. Conclusion: In our study, it was observed that the levels of LCN 1 in tears of patients with Proliferative Diabetic Retinopathy was decreased as compared to the levels of LCN 1 in tears of Non-Proliferative Diabetic Retinopathy and cases with no Diabetes Retinopathy. Establishment of this correlation has possible implications for screening of Diabetic Retinopathy in patients of Diabetes. However, larger studies with greater number of cases are needed to establish the definitive role of LCN1, as a screening tool for Diabetic Retinopathy.