Using an oral omega-3 fatty acid supplement to manage dry eye disease (DED) signs and symptoms offers no improvement over a placebo, a new study found.

The Dry Eye and Assessment Management (DREAM) Study, a randomized clinical trial, set out to gauge the long-term safety and efficacy of omega-3 fatty acids for DED treatment. “Many clinicians recommend and many patients take dietary supplements of n−3 fatty acids (often called omega-3 fatty acids), because they have anti-inflammatory activity and are not associated with substantial side effects,” the study said.

Researchers randomly assigned 535 patients with moderate to severe DED to receive a daily oral dose of either 3000mg of fish-derived n−3 eicosapentaenoic and docosahexaenoic acids or an olive oil placebo. They primarily looked at mean change in Ocular Surface Disease Index (OSDI) score at six and 12 months, but they also monitored mean changes in conjunctival staining score, corneal staining score, tear film break-up time (TBUT) and Schirmer’s test score to assess supplement efficacy. The results were less than encouraging for use of omega-3 supplementation as a possible dry eye solution, however.

After one year of supplementation, the mean OSDI score change was not significantly different between the omega-3 group and placebo. There was also no significant difference in conjunctival staining score, corneal staining score, TBUT and Schirmer’s test score between the groups.

These results come as a surprise to those who have followed recent positive reports associated with omega-3 fatty acids. “Given the number of other studies that support fish oil, it's definitely a surprise to hear this outcome,” says Jeffrey Anshel, OD, of Encinitas, CA. “However, I am one who agrees that fish oil does not represent the ‘whole story’ on treating DED.” Instead Dr. Anshel uses a product with “some fish oil in addition to several other ingredients to address the anterior ocular structures.” 

Additionally, Dr. Anshel notes that this study may not represent the omega-3 fatty acids as a whole. “Given that many of the trial participants were already using other treatments upon recruitment and continued to use them throughout the study, this was not a study of omega-3 alone,” he says. According to the study, many patients were also treated using included artificial tears, cyclosporine drops, warm lid soaks, lid scrubs or baby shampoo and ‘other’ treatments. “Although the study was well designed, this is a curious aspect to consider,” Dr. Anshel says.

The Dry Eye Assessment and Management Study Research Group. n−3 fatty acid supplementation for the treatment of dry eye disease. N Engl J Med. April 13, 2018. [Epub ahead of print].