Abstract
BACKGROUND: Dry eye disease (DED), often associated with meibomian gland dysfunction (MGD), affects millions globally, yet effective treatments remain limited. Sunflower lecithin, rich in phosphatidylcholine, may enhance lipid secretions from the meibomian glands, potentially stabilizing the tear film and reducing evaporative loss. We tested the hypothesis that sunflower lecithin supplementation can improve the signs and symptoms of DED in adults with MGD. METHODS: In this double-blind, single-center clinical trial, 31 patients with DED were randomized in a 2:1 ratio to receive either sunflower lecithin (4,800 mg/day) or placebo (4,000 mg olive oil/day) for 90 days. At baseline and the end of the study, DED symptoms were evaluated using the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire. DED signs were evaluated through tear film breakup time (TBUT), meibomian gland score (MGS), and ocular surface inflammation, measured via matrix metalloproteinase-9 (MMP-9) detection using the InflammaDry test (QuidelOrtho, San Diego, USA). For both groups, mean changes were calculated, and unpaired t-tests were used to compare mean values between groups with statistical significance set at P<0.05. Additionally, the mean difference between the active and placebo groups was calculated for each outcome to quantify the magnitude of improvement or worsening in the active group relative to placebo. Results: Active and placebo groups showed decreases in SPEED scores with mean changes of -3.21 ± 1.47 and -1.50 ± 3.34 points, respectively, resulting in a mean difference of -1.71 (95% CI: -5.36 to 1.94; P=0.29). TBUT, MGS, and InflammaDry results improved in both groups but showed no significant differences between groups. Both groups exhibited improvements across all metrics with no significant differences. CONCLUSION: Sunflower lecithin supplementation did not demonstrate a significant therapeutic benefit over placebo in improving MGD-related DED signs or symptoms. Further research with larger sample sizes, longer follow-up, and combination therapies is recommended to explore the potential role of phospholipids in DED management.