Complementary and Alternative Medicine to Treat Dry Eye Disease

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Complementary and Alternative Medicine to Treat Dry Eye Disease


Janine A. Smith





Key Points



  1. ♦ Complementary and alternative medicine (CAM) is defined as a “group of diverse medical and health care systems, therapies, and products that are not presently considered to be part of conventional medicine.” Sixty-two percent of Americans report some use of CAM in the last year.
  2. ♦ With few exceptions, the quality of studies of CAM for the treatment of dry eye published in the peer-reviewed scientific literature is less than desirable. It is critical that randomized controlled trials of CAM be performed to appropriately evaluate potential new CAM treatments, just as are performed for any conventional medication or treatment modality.
  3. ♦ Randomized controlled trials of acupuncture for dry eye, including Sjögren’s syndrome, have been performed, but mixed results have been reported. It is difficult to design a control treatment arm for a study of acupuncture because of the nature of the treatment.
  4. ♦ There is sufficient biologic plausibility that essential fatty acid administration might have an impact on ocular surface health by affecting inflammatory mediators or through biochemical effects on cell function. Two randomized controlled trials of essential fatty acid for the treatment of dry eye have been performed. In one study, subjects who received linoleic acid and gamma linolenic acid demonstrated significant decreases in symptoms, ocular surface staining, and HLA-DR expression, but not in tear breakup time or Schirmer’s 1 test. In another study performed on participants who had undergone photorefractive keratectomy, linoleic acid and gamma linolenic acid administration was associated with a significant improvement in symptoms, tear clearance, and tear production.
  5. ♦ Randomized controlled studies of dehydroepiandrosterone have been disappointing, with some reports of improvement in nonocular manifestations of Sjögren’s syndrome but no evidence of efficacy for oral or ocular dryness.
  6. ♦ Although a significant body of literature demonstrates the critical role of androgens in maintaining lacrimal gland function and reports low levels of circulating androgens of various types in different dry eye populations, there are no published reports of successful treatment of any type of dry eye with topical application of any androgen formulation.

Dry eye disease is a common condition for which many patients have sought relief from the symptoms of ocular irritation through complementary and alternative medicine (CAM). Complementary and alternative medicine is a “group of diverse medical and health care systems, therapies, and products that are not presently considered to be part of conventional medicine.” Sixty-two percent of Americans reported use of some CAM in the last year, based on data obtained from the National Health Interview Survey conducted by the National Centers for Disease Control and Prevention’s National Center for Health Statistics.1 The 10 most common CAM therapies were prayer for one’s own health (43%), prayer for other’s health (24.4%), natural products (18.9%), deep breathing exercises (11.6%), prayer group (9.6%), meditation (7.6%), chiropractic care (7.5%), yoga (5.1%), massage (5%), and diet-based therapies (3.5%). Nineteen percent of adults used natural products, including herbal medicine, functional foods (garlic), and animal-based (glucosamine) supplements during the past year. Although the most commonly treated conditions were back pain, colds, neck pain, joint pain, or depression, CAM use for other indications included hypertension and menopause.


All exogenous agents administered as “medications,” or “therapies” can cause adverse effects and should be tested for evidence of efficacy in a randomized placebo-controlled clinical trial. Unfortunately, few systematic reviews and randomized controlled trials of CAM therapies are available for ocular conditions.2 Therefore, physicians often do not have sufficient information to recommend or prescribe alternative therapeutics as is required to meet the same stringent criteria as conventional medications. Although herbal medications are often viewed by the consumer as harmless, these compounds can have deleterious effects, and the combination of CAM modalities and conventional medications can cause serious adverse effects, including drug interactions such as lowering or raising circulating levels of medications with potential associated toxicity. To take the best care of patients, clinicians must critically review existing literature to scientifically evaluate the usefulness of CAMs because many patients are using them and need our guidance as well as medical care.


The most frequently employed CAM therapeutics for dry eye are acupuncture, nutritional and dietary supplements, herbal or botanical medicines, and homeopathy.


♦ Acupuncture


Acupuncture is part of traditional Chinese medicine and has been practiced among non-Chinese in the United States, Europe, and elsewhere for less than 50 years for the treatment of many medical conditions as well as pain management. It is most often employed as palliative medicine. Its mechanism of action has not been completely established; however, acupuncture has the potential to affect both the central and peripheral nervous systems through neurotransmitters, as demonstrated in animal models. Traditional Chinese practitioners explain that acupuncture exerts therapeutic effects through removing blockage of qi (pronounced “chee”). Immunological and psychological effects, including the placebo effect, are also purported. Acupuncture is an established adjuvant analgesic modality for the treatment of chronic pain. One problem is the difficulty in designing a placebo treatment other than a sham application, which participants could easily detect. Evaluation of the clinical efficacy of sensory nerve stimulation modality is almost impossible to perform and crossover study designs are not appropriate due to the potential for carry over or long-term effects. Standardization of the acupuncture treatment methods, that is, needle versus laser, and application procedures are also important. There are few reported adverse events associated with acupuncture, in contrast to those associated with some other alternative medicines such as herbal remedies.


In a randomized controlled trial, 12 patients with keratoconjunctivitis sicca (KCS) received acupuncture sessions of 30 minutes one or two times per week, and 13 subjects were placed in the control group without sham or other placebo treatment. All subjects received artificial tears but no other treatments. There was no difference in the change in total number of symptoms within or between groups. Using the Visual Analogue Scale (translated to better, no change, or worse), six of 12 acupuncture-treated subjects and none of 13 subjects in the control group felt worse at the first follow-up visit (p = .036) and two control patients felt worse at the second follow-up visit; however, there was no significant difference between the groups. There were no significant differences in tear breakup time (BUT), rose bengal staining, frequency of artificial tear use, and dry eye signs between treatment groups. Bizarrely, this article reports a significant increase in Schirmer’s 1 test score without anesthesia for the left eyes but not the right eyes. Mean Schirmer’s 1 test score at baseline for the acupuncture group was 5.2 mm/5 minutes for the left eye and 6.2 mm/5 minutes for the right eye; for the control group, this result was 6.2 mm/5 minutes for the left eye and 3.6 mm/5 minutes for the right eye. Mean Schirmer’s 1 test score at follow-up visit 2 was 6.2 mm/5 minutes for the left eye and 7.7 mm/5 minutes for the right eye, and 6.8 mm/5 minutes for the left eye and 5.1 mm/5 minutes for the right eye for the control group.3


Nepp and colleagues published a report of a randomized controlled trial of acupuncture for dry eye in 1998.4 This article used the National Eye Institute/Industry workshop definition of dry eye as a “disorder of the tear film due to tear deficiency or excessive tear evaporation, which causes damage to the interpalpebral ocular surface and is associated with symptoms of ocular discomfort” as the entry criteria for a randomized, double-masked trial of 114 patients, with a mean age of 57.6 years, of which 87% were women.5 Thirty participants were randomized to treatment with infrared laser (4 mW, 780 nm, gallium-aluminum arsenide) or to sham laser procedure performed weekly for 10 weeks. Thirty participants received needle acupuncture in which local points (GB1, UB2, ST5, Ex2YinTang), specific points for eyes and mucosa (LI4, LI3, Kd6, TH5), and individual points were selected based on ophthalmic and general questionnaires. Sessions lasted for 30 minutes and were repeated weekly for 10 weeks. It is unclear whether needle acupuncture subjects were randomized as well. Participants underwent slit lamp exam before and 1 week after the last treatment, and outcome measures included Schirmer’s 1 test, tear BUT, and drop frequency. Twenty-two participants received artificial tears alone.


The article reported the prevalence of the findings from each treatment group within several categories of the three outcome measures:



  1. ♦ Schirmer’s 1 test score: normal, more than 10 mm; low, more than 5 but less than 10 mm; and severe-pathologic, less than 5 mm
  2. ♦ Tear BUT: normal, more than 10 seconds; low, 5 to 9 seconds, severe-pathologic, 0 to 4 seconds
  3. ♦ Use of artificial tears, in times per day: 0, 1 to 3, 4 to 10, or more than 10

Descriptive statistics were not presented. Graphs depicting the percentage of participants in each category of each outcome, comparing the laser-treated with the shamtreated groups, are presented. In the most severe categories for each outcome, the sham laser-treated proportion exceeds that of the true laser-treated group. The authors reported “significant differences” between the laser-treated versus sham-treated participants and “nonsignificant differences” between the sham laser and artificial tear control group; although not stated, presumably this difference is based on the proportion of participants per category, as these are the only data presented. No information is presented on the actual mean, median, or range of Schirmer’s 1 test scores, tear BUT, or frequency of drop usage.


Nepp and colleagues published an article in 2002 on the usefulness of acupuncture in treating ophthalmologic pain.6 It described case reports of successful acupuncture treatment of painful ophthalmic conditions such as Tolosa-Hunt syndrome, ophthalmic migraine, blepharospasm, and dry eye. Based on statistically significant reduction in visual analogue scale pain assessments before and after treatments, the authors called for additional studies.


Reduction in pain, increase in secretions, decrease in temperature, and decrease in psychological stress are all potential strategies for acupuncture treatment of dry eye. Temperature is an important aspect of traditional Chinese medicine. In a nonrandomized study, Nepp demonstrated that acupuncture can decrease periorbital temperature as measured by a noncontact infrared thermometer (THI 500; TASCO, Osaka, Japan).7 This treatment was not associated with a decrease in overall body temperature, and there was no significant improvement in Schirmer’s 1 test results, but there were significant improvements in tear BUT, lipid layer thickness, and frequency of artificial tear use.


Studies of acupuncture in Sjögren’s syndrome have had mixed results. In a study by List et al,8 34 patients with Sjögren’s syndrome were randomly assigned to receive either 10 weeks of acupuncture (9 with manual stimulation) or no treatment, with the control group then receiving 10 weeks of acupuncture after the control period. Acupuncture has been demonstrated to increase unstimulated saliva production in normal individuals, presumably through increased blood flow and release of neuropeptides. It showed no significant improvements in unstimulated saliva secretion in the patients with Sjögren’s syndrome. There was a significant decrease in subjective experience of mouth dryness, however, but no other subjective variables, for acupuncture-treated participants. Interestingly, there was a significant reduction in subjective eye dryness in the group that received no treatment for the first 10 weeks and then received acupuncture. The authors concluded that there was little or no treatment effect on salivary flow although positive effects of subjective improvement were reported by patients. This may have been due to increased relaxation, increased sense of moisture in the mouth, or improved sleep, all of which have been reported with acupuncture. In contrast, Blom and Lundeberg found a statistically significant increase in unstimulated and stimulated salivary flow rates after 24 consecutive acupuncture treatments. Furthermore, participants who continued undergoing acupuncture over a 3-year period maintained significantly higher saliva production than those who did not.9 In a clinical study of 50 patients with radiation-induced xerostomia, acupuncture resulted in a better than 10% improvement in median palliation as measured and validated by the Xerostomia Inventory.10


♦ Nutritional and Dietary Supplements


Nutritional and dietary supplements are not submitted to the U.S. Food and Drug Administration (FDA) for approval for a specific indication as are traditional pharmaceutical agents. Both the FDA and the Federal Trade Commission, however, have some regulatory oversight designed to protect the American people from harmful preparation and false advertising. Indeed, dietary supplements must meet the strict manufacturing requirements of the Good Manufacturing Practices, which incorporate potency, cleanliness, and stability. There are about 50 essential nutrients, including vitamins and minerals, and many patients do not consider them to have medicinal properties and must be specifically queried for their use. Some vitamins and nutritional supplements can be toxic if ingested in megadoses, concomitant with medications in the setting of some diseases.


Vitamin A is well recognized to be critical to the health of the ocular surface epithelium, but vitamin A deficiency is rare in populations in industrialized nations. Vitamin A may play an important role in supporting the epithelial structures of the lacrimal and meibomian glands, as well as the ocular surface. Several vitamins, including A and E, are antioxidants and may also play an important role in protecting cell membranes from damage by oxidation and lipid peroxidation from free radicals. Airborne pollutants serve as environmental oxidative stressors to the tear film and play an underestimated role in chronic dry eye. Cigarette smoke is a source of free radicals, can exacerbate symptoms of dry eye disease, and has now been associated with an increased risk of dry eye.11 Moreover, smoking has been found to have a deleterious effect on tear proteins.12


Patel and Grierson showed that supplemental multivitamins can improve tear film stability within 10 days in a non-dry eye, healthy Western population. Importantly, the multivitamin had more predictable effects than any one vitamin or mineral given alone.13

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Jun 4, 2016 | Posted by in OPHTHALMOLOGY | Comments Off on Complementary and Alternative Medicine to Treat Dry Eye Disease

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