EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
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88 EW CORNEA October 2012 Omega-3 and dry eye by Vanessa Caceres EyeWorld Contributing Writer Looking at science and clinical experience O mega-3 fatty acids seem like a cure-all for just about anything that ails patients nowadays. They're hailed for pro- moting better heart health, reducing inflammation, providing more lus- trous hair and skin, and even pro- moting better mood. The question is, how beneficial are omega-3s for dry eye patients? "We're in the infancy stages of understanding what this is and what it does for dry eye," said Robert Latkany, M.D., founder and director, Dry Eye Clinic, New York Eye and Ear Infirmary, New York. Right now, ophthalmologists are using the fledgling research that is available along with their clinical experience to decide whether or not they will recommend omega-3 sup- plementation to dry eye patients. The research Some recent research has tried to pin down the specific effects of omega-3 supplementation on dry eye. In a pilot, double-masked study pub- lished in March 2011 in Cornea, investigators gave patients various doses of fish oil and flaxseed oil (TheraTears Nutrition, Advanced Vision Research, Woburn, Mass.) for 3 months. Investigators measured patients' subjective symptoms and tested for tear breakup time and corneal staining as well as perform- ing other tests. Of the 36 patients included, 70% of the patients receiving treat- ment became asymptomatic. In the placebo group, 37% of the sympto- matic patients became asympto- matic. Schirmer's testing and fluorophotometry seemed to indi- cate that omega-3 use increased tear secretion, according to investigators. Although those results are promising, they only begin to reveal how omega-3 might help dry eye and which patients would benefit the most, Dr. Latkany said. A study presented at the 2012 Association for Research in Vision and Ophthalmology (ARVO) meet- ing in Ft. Lauderdale, Fla., and spon- sored by ScienceBased Health (Houston) focused on omega-3 and gamma-linolenic acid (GLA) therapy (HydroEye) taken for 6 months by 38 postmenopausal women who had keratoconjunctivitis sicca. The double-blind, placebo-controlled, prospective, randomized, multi- center trial found that patient self- reported symptoms by OSDI (Ocular Surface Disease Index) as well as conjucnctival impression cytology CD11c and HLA-DR inflammation biomarkers statistically significantly improved after the study duration, said lead investigator John D. Sheppard, M.D., professor of ophthalmology, microbiology, and immunology, Eastern Virginia Medical School, Norfolk, Va. The study did not seem to detect differ- ences in corneal staining or tear breakup time, but topographic corneal surface regularity stabilized significantly with the study supple- mentation compared to placebo. At the 2012 ASCRS•ASOA Sym- posium & Congress, Frank A. Bucci Jr., M.D., founder, Bucci Laser Vision, Wilkes-Barre, Pa., presented the results from a study sponsored by Physician Recommended Nu- triceuticals (PRN, Plymouth Meet- ing, Pa.), which makes PRN Dry Eye Omega Benefits. The multicenter, blinded, randomized study random- ized 60 patients to receive the PRN product, a Nature Made omega-3 product (Pharmavite, Northridge, Calif.), or TheraTears Nutrition. Investigators measured red blood cell membrane saturation of the omega-3 products at baseline, 1 and 3 months follow-up. Investigators found that red blood cell saturation was significantly greater for the PRN product compared with the other two products. Knowing how well an omega-3 product can be absorbed in the body is crucial in ensuring it will provide key health benefits to the eyes and elsewhere, Dr. Bucci said. Although there have been other studies related to dry eye and omega-3 supplementation, there has yet to be a large-scale clinical trial that pinpoints how omega-3 fatty acids work to treat dry eye and what kind of dosing is appropriate. Penny A. Asbell, M.D., professor of oph- thalmology, director, Cornea and Refractive Services, Department of Ophthalmology, Mount Sinai School of Medicine, New York, hopes to find those answers via a clinical trial slated to get under way with the National Eye Institute. "With omega-3 and dry eye, we have small trials but little in the way of double- masked, randomized, controlled trials," she said. The trial she is working on will look beyond the claims of omega-3 benefits for gen- eral health to show how the supple- mentation can benefit dry eye. "It behooves us to find out how this works," she said. The trial should also reveal more information on the epidemiology of dry eye, Dr. Asbell added. Clinical experience Despite what research may find, what is key is how patients respond to omega-3 use. "It's all meaningless if patients don't feel better," Dr. Latkany said.