Improvement of dry eye symptoms with polyunsaturated fatty acids
Résumé
Purpose: Polyunsaturated fatty acids (PUFA) are involved in inflammatory pathways via prostaglandins. Conjunctival inflammation is a hallmark of all dry eye syndromes. We investigated the role of dietary n–6 and n–3 fatty acids in patients suffering from ocular dryness with peculiar attention to inflammatory markers. Methods: 70 patients presenting with mild to moderate dry eye syndromes were randomly assigned to Nutrilarm® or placebo pills, thrice a day for 6 months. Schirmer test, BUT, fluorescein and lissamin green stainings were performed at inclusion and after 1, 3 and 6 months. Impression cytology to evaluate MHCII antigens was harvested at D0, Month 3 and 6. Tear PGE1 levels were measured at D0, Month 1, 3 and 6. Furthermore, a questionnaire related to the dry eye symptoms and global discomfort was provided at every visit. Results: Schirmer test, BUT, fluorescein and lissamin green stainings were improved with treatment when compared to placebo but the difference remained non statistically significant. We found the same trend with MHCII and prostaglandin tear secretion as well as discomfort feeling (p=0.091). Efficacy evaluated by the patients and the investigator was nearly significant (p=0.052 and p=0.054 respectively). For some signs, such as reflex tearing and conjunctival hyperaemia, the improvement was nearly significant (p=0.047 and 0.045, respectively). The same results were found with skin quality and emotional condition which were improved (61% with treatment vs 36% with placebo). Conclusion: This double–masked, pilot study shows that PUFAs seem an interesting tool to alleviate the symptoms related to dry eye syndrome. These results should be confirmed using a larger study population.