Pilot, Prospective, Randomized, Double-masked, Placebo-controlled Clinical Trial of an Omega-3 Supplement for Dry Eye
Pilot, Prospective, Randomized, Double-masked, Placebo-controlled Clinical Trial of an Omega-3 Supplement for Dry Eye
Year: 2011
Authors: Wojtowicz, J.C. Butovich, I. Uchiyama, E. Aronowicz, J. Agee, S. McCulley, J.P.
Publication Name: Cornea
Publication Details: Volume 30; Number 3; Pages 308 -314.
Abstract:
To investigate the potential effect of dietary supplementation with omega-3 fatty acid on lipid composition of meibum, aqueous tear evaporation, and tear volume in patients with dry eye.
Methods: In a pilot, prospective, randomized, double-masked study, patients with dry eye received a daily dose of fish oil, containing 450 mg of eicosapentaenoic acid, 300 mg of docosahexaenoic acid, and 1000 mg of flaxseed oil (TheraTears Nutrition; Advanced Vision
Research, Woburn, MA) for 90 days. There were 2 patient visits: baseline and final. At these visits, patients completed the ocular surface disease index to score subjective symptoms, and slit-lamp examinations, breakup time, corneal staining, Schirmer type I, fluorophotometry, evaporometry, and collection of meibomian gland secretion samples for lipid composition analysis were performed. A total of 36 patients with dry eye completed the study. At the end of the study, 70% of the patients became asymptomatic, whereas for the placebo group, 7% of the symptomatic patients became asymptomatic. Schirmer testing and fluorophotometry suggested that the omega-3 supplement increased tear secretion. The lipid composition of the samples collected from the omega-3 group was found to be very similar to that from the placebo group. No trends between groups were seen for other objective parameters. Dietary supplementation with omega-3 fatty acids in dry eye showed no significant effect in meibum lipid composition or aqueous tear evaporation rate. On the other hand, the average tear production and tear volume was increased in the omega-3 group as indicated by both Schirmer testing and fluorophotometry. (Author's abstract)
Methods: In a pilot, prospective, randomized, double-masked study, patients with dry eye received a daily dose of fish oil, containing 450 mg of eicosapentaenoic acid, 300 mg of docosahexaenoic acid, and 1000 mg of flaxseed oil (TheraTears Nutrition; Advanced Vision
Research, Woburn, MA) for 90 days. There were 2 patient visits: baseline and final. At these visits, patients completed the ocular surface disease index to score subjective symptoms, and slit-lamp examinations, breakup time, corneal staining, Schirmer type I, fluorophotometry, evaporometry, and collection of meibomian gland secretion samples for lipid composition analysis were performed. A total of 36 patients with dry eye completed the study. At the end of the study, 70% of the patients became asymptomatic, whereas for the placebo group, 7% of the symptomatic patients became asymptomatic. Schirmer testing and fluorophotometry suggested that the omega-3 supplement increased tear secretion. The lipid composition of the samples collected from the omega-3 group was found to be very similar to that from the placebo group. No trends between groups were seen for other objective parameters. Dietary supplementation with omega-3 fatty acids in dry eye showed no significant effect in meibum lipid composition or aqueous tear evaporation rate. On the other hand, the average tear production and tear volume was increased in the omega-3 group as indicated by both Schirmer testing and fluorophotometry. (Author's abstract)
The core mechanisms of dry eye have been associated with tear hyperosmolarity and tear film instability. Tear hyperosmolarity is regarded as the central mechanism causing ocular surface inflammation, damage, and symptoms and the initiation of compensatory events in dry eye. An association between the dietary intake of omega-3 (n-3s) with changes in the meibomian gland oils, and its implications in dry eye disease has been reported. Topical application of ALA has been shown in dry eye induced in mice to significantly decrease corneal fluorescein staining, CD11b+ cell number, and expression of cornea interleukin (IL)-1a and corneal and conjunctival tumor necrosis factor (TFN)-a as compared with topical linoleic acid (LA). The present pilot study was performed to investigate the effect of flaxseed and fish oils dietary supplementation on the tear film and the ocular surface. Although this pilot study was underpowered to achieve statistical significance, with 36 patients, 21 in the active group and 15 in the placebo group, the average tear production and tear volume was increased in the omega-3 group as indicated by both Schirmer testing and fluorophotometry. Thus the omega-3 supplements improved dry eye symptoms but without a significant effect in meibum lipid composition or aqueous tear. these results are not consistent with others showing that ALA topical application in dry eye showed a statistically significant difference in corneal fluorescein staining, CD11b+ cell number and expression of cornea IL-1a and corneal and conjunctival TFN-as compared with topical LA.
Gaps exist in data regarding how dietary supplementation with long chain omega-3 fatty acid can affect dry eye physiopathology. This study suggests that the most promising endpoints for a larger clinical trial would include dry eye symptoms, Schirmer test results, and fluorophotometry. (Editor's comments)
Gaps exist in data regarding how dietary supplementation with long chain omega-3 fatty acid can affect dry eye physiopathology. This study suggests that the most promising endpoints for a larger clinical trial would include dry eye symptoms, Schirmer test results, and fluorophotometry. (Editor's comments)
