Changes in tear lipid layer thickness and symptoms following the use of artificial tears with and without omega-3 fatty acids: A randomized, double-masked, crossover study

Abstract

Purpose: To determine if an eye drop containing omega-3 fatty acids (Refresh Optive MEGA-3®, Allergan plc, Dublin, Ireland) increases the lipid layer thickness (LLT) of the tear film versus a non-emollient eye drop (Refresh Optive, Allergan plc). Methods: Patients (≥30 years) with baseline LLT ≤75 nm completed the Current Symptoms Survey (CSS – a visual analog survey of dry eye symptoms), and LLT was measured pre-and post-instillation (15 and 60 mins) of their randomly assigned treatment. After washout, patients were tested with the other treatment. Primary endpoint: change in LLT from baseline. Secondary endpoint: CSS results. Results: Of 21 patients enrolled, 19 completed the study. With the omega-3–containing eye drop, the mean (standard deviation) LLT increase from baseline at 15 mins was statistically significant in the overall field (8.8 [11.5] nm; P<0.001), and in each individual zone (super-ior, central, and inferior). At 1 hr, the LLT change from baseline was statistically significant overall (4.4 [9.7] nm; P<0.02) and in the inferior and central zones. With the aqueous eye drop, LLT change from baseline was only significant at 15 mins in the inferior field. The CSS analysis revealed a ≥8.68-unit decrease in mean average dryness score from baseline at 15 and 60 mins post-instillation of the lipid-based treatment (P≤0.03). Conclusion: The eye drop containing omega-3 fatty acids increased LLT at 15 mins, maintaining it at 1 hr post-instillation. Dryness symptoms also improved and maintained improved levels 1 hr after instillation, indicating that the product may benefit symptomatic patients with evaporative dry eye.