Effect of Omega-3 Fatty Acids Dietary Supplementation on Ocular Surface and Tear Film in Diabetic Patients with Dry Eye

Objective: The objective of this study was to investigate the effect of dietary supplementation with omega-3 fatty acids on ocular surface and tear film in patients with type 2 diabetes suffering from dry eye. Methods: Thirty-six patients suffering from type 2 diabetes and moderate to severe dry eye syndrome were included in the study. Patients were assigned to receive omega-3 long-chain polyunsaturated fatty acids for 3 months. Tear film break-up time test, Schirmer-I test, and conjunctival impression cytology analysis were performed on all patients at baseline and after 1 and 3 months. The subjective symptoms of dry eye were evaluated with the Ocular Surface Disease Index (OSDI) questionnaire at the same time points. Results: Patients' average age was 65.57 +/- 4.27 years and the mean duration of diabetes was 14.85 +/- 5.4 years. There was a statistically significant increase in Schirmer-I test results and tear break-up time score after 3 months of supplementary intake of omega-3 fatty acids compared to baseline (p < 0.05 and p < 0.001, respectively). Impression cytology demonstrated a significantly lower grade of conjunctival squamous cell metaplasia after 1 and 3 months of omega-3 fatty acids intake compared to baseline (p < 0.05 and p < 0.01, respectively). The OSDI score was statistically significant lower both at 1 and 3 months after omega-3 fatty acids supplementation compared to baseline (p < 0.001). Conclusions: Omega-3 fatty acids may effectively improve tear film characteristics, reverse ocular surface features, and alleviate the subjective symptoms associated with dry eye syndrome in patients with type 2 diabetes.