Data show 1 g per day of marine ω-3 fatty acid for 5.3 years showed no effect on incident clinically diagnosed DED or reported severe DED symptoms.
New research from a recent randomized clinical trial does not support the recommendation of marine ω-3 fatty acid supplementation to reduce the incidence of dry eye disease (DED).
The data suggest that supplementation with 1 g per day of ω-3 fatty acid for 5.3 years had no effect on incident clinically diagnosed DED or reported severe DED symptoms.
“Our finding that long-term supplemental use of ω-3 had no material effect on DED incidence appears broadly consistent with the null findings for DED signs and symptoms observed in the [Dry Eye Assessment and Management] DREAM study,” wrote study author William G. Christen, ScD, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School.
Basic science studies reported beneficial effects with ω-3 fatty acids in inflammatory processes implicated in the pathogenesis of DED, but few studies have investigated its efficacy in preventing the onset of the disease, according to investigators.
Thus, the current study presented ancillary findings for incident DED from the randomized, double-blind, placebo-controlled Vitamin D and Omega-3 Trial (VITAL) with the prespecified VITAL-Dry Eye. The nationwide 2 x 2 factorial trial investigated vitamin D and marine ω-3 acids in the primary prevention of cancer and cardiovascular disease.
From 25,871 participants randomized in the parent VITAL trial, exclusions in VITAL Dry-Eye left a total of 23,523 US adults who were free of a previous diagnosis of DED and were not experiencing severe dry eye symptoms at study entry.
The randomization to ω-3 fatty acids, vitamin D, both active agents, or both placebos occurred from November 2011 to March 2014 and was computer generated within sex, 5-year age groups, and race, according to investigators.
The primary endpoint was identified as incident clinically diagnosed DED confirmed by review of medical records, followed by a composite of all confirmed incident clinically diagnosed DED cases plus all incident reports of severe DED symptoms for the secondary endpoint.
Data show the mean age of participants in the analysis was 67.0 years and 5678 participants (48.3%) were women. Moreover, 4610 participants (20.0%) self-identified as Black, 16,481 (71.6%) self-identified as non-Hispanic White, and 1927 (8.4%) self-identified as another racial or ethnic group or declined to respond.
Over a median of 5.3 years of treatment and follow-up, 472 of 23,523 participants (2.0%) experienced a medical record-confirmed diagnosis of indecent DED, the primary study endpoint. They found no difference in diagnosed DED by randomized ω-3 fatty acid assignment (232 of 11,757 participants [2.0%] with end points in the treated group vs 240 of 11,766 participants [2.0%] with end points in the placebo group; hazard ratio, 0.97; 95% CI, 0.81 - 1.16).
Additionally, no difference between groups for the secondary endpoint of diagnosed DED plus incidence severe DED symptoms was observed by investigators (1044 participants [8.9%] with end points in the treated group vs 1074 [9.1%] with endpoints in the placebo group; hazard ratio, 0.97; 95% CI, 0.89 - 1.06).
The study, “Efficacy of Marine ω-3 Fatty Acid Supplementation vs Placebo in Reducing Incidence of Dry Eye Disease in Healthy US Adults: A Randomized Clinical Trial,” was published in JAMA Ophthalmology.