Nutritional supplements may have future in treating patients with tear dysfunction

Nutritional supplements seem to make sense in the treatment of tear dysfunction, according toMarian Macsai, MD. Dr. Macsai tempered her assertion with the observation that no objectivetrials have been performed to support the use of nutritional supplements in patients with teardeficiency.

Dry eye disease has an underlying inflammatory component that results in decreased aqueous tearproduction and increased evaporative tear loss. Fatty acid metabolism is a hot topic in thisregard because omega 3 metabolizes into anti-inflammatory eicosanoids and thrombolytic agents,and omega 6 metabolism is key in the production of arachadonic acid and other inflammatorymediators and platelet aggregators. A shift in the omega 3:omega 6 fatty acids ratio to 2.3:1from the average American ratio of 10:1, toward omega 3 can lower the overall inflammatorystate in the body and a decreased risk of clinically diagnosed dry eye, according to Dr.Macsai, professor and vice chairwoman, Department of Ophthalmology, Northwestern University,Glenview, IL.

"The risk of dry eye decreased by about 30% per additional gram of omega 3 consumed per day inthe Women's Health Study," she said. In addition, omega-3 supplementation has a positive effecton asthma, cardiovascular disease, arthritis, depression, and adult-onset diabetes.

Flaxseed oil, which belongs to omega-3 fatty acids, is believed to reduce inflammation byinhibiting tumor necrosis factor-alpha and interleukin-1 beta. Supplementation with fish oil,another hot topic, inhibits the omega 6 pathway. Dr. Macsai pointed out that treating patientswith Sjögren's syndrome with flaxseed oil, fish oil, and vitamin E significantly improved dryeye and dry mouth symptoms. However, bilberry and evening primrose oil seem to have nosignificant effects in patients with dry eye.

"Nutritional supplementation probably should be used in patients with dry eye. Vitamin E may ormay not be needed. Theoretically, this supplementation makes sense," Dr. Macsai said. She notedthat the coagulation effect of those nutritional supplements must be kept in mind, however,especially for patients who are undergoing elective surgery. There has been no objectiveplacebo-control trial conducted to support their use.

In addition, subjection symptoms of dry eye may be related to underlying depression resultingfrom dry eye. Another consideration is that in patients who have undergone gastric bypasssurgery, these nutrients will not be absorbed.