Article Date: 6/1/2004

nutrition
New Tools for Therapy
What role will vitamins and supplements play in the care of your patients?
J. JAMES THIMONS, O.D., F.A.A.O., Fairfield, Conn.

The new millennium has ushered in numerous changes. None will have a greater impact than nutraceuticals as tools for therapeutic intervention.

Patients' use of vitamins and supplements has risen dramatically. In many offices 75% or more of our patients use them. We must ask, what role do these agents play in therapeutic care? Do we have credible scientific evidence to support their use?

Examine the evidence

Scientific support has been established for nutraceuticals in the management of ocular surface disease and age-related macular degeneration (AMD). Kunert, Phlugphelder, Stern and Yeh has defined the etiology of the dry eye syndrome (DES) as inflammation. Its relationship to autoimmune diseases such as Sjogren's syndrome, rheumatoid arthritis, vasculitis, etc., is well established and gives us a clearer understanding of ocular symptoms of this systemically mediated disease.

The role of the hormone androgen and its impact on pre-, peri- and post-menopausal females gives us new insights into the patho-physiology and therapy for DES. Other sources of dry eye complaints include chronic contact lens wear, computer use, OTCs and the environment, all of which can produce inflammatory changes that result in DES.

Nutraceuticals act to block the development of inflammation on the ocular surface. Anti-inflammatory properties are attributed to numerous agents, including Omega 3 oils, Gamma linolenic acid (GLA), Vitamin E, bilberry and organic fruits and vegetables for vital phytonutrients. Transcription factors (proteins that bind to DNA and control gene expression) are vital to the function of the immune system and control a wide range of cellular activities, including the development of inflammation and cellular proliferation. Agents such as Omega 3 essential fatty acids and Vitamin E neutralize NK-fB, a key transcription factor, and have additional actions on luekotrienes, which are part of the inflammatory cascade. GLA, found in black current seed oil and borage oil, is a potent inhibitor of inflammation.

A recent study showed that patients with keratoconjunctivitis sicca who consumed GLA had statistically significant changes in dry eye symptoms. Sullivan and Boerner demonstrated that Omega 3 essential fatty acids are the basic building blocks in the development of meibum and normal miebomian function.

What does it mean for you?

How does the clinician translate information into effective outcomes? The first and most important step is to implement a standard dosing regimen that will serve as a basis for clinical analysis. It's vital to take advantage of the full spectrum of agents available to combat inflammation. These include Omega 3 fatty acids, vitamin E, GLA, Flaxseed oil and Bilberry. Numerous sources of these products are available, so the ability of the clinician to confirm dosing levels and product quality makes it difficult to derive consistent therapy and subsequent analysis. For that reason, it's better to use a commercially available product that has been developed for ophthalmic therapy. It will provide consistent dosing patterns and manufacturing quality.

We typically place patients on once a day oral therapy (2000mg) either as a sole agent or in conjunction with other interventions such as Restasis, doxycycline and/or topical steroids. After we achieve an initial response, we modify the therapy to reflect the patient's clinical signs and symptoms.

Vitamins and AMD

Nutraceutical therapy has impacted AMD. The publication of the AREDS Study by the National Eye Institute places the questions of who to treat and what to use on every primary care clinician.

Several important issues arise in making the decision to begin AMD therapy. The first is who to treat. The AREDS study inclusion criteria included the presence of drusen, RPE changes, and decreased acuity. It did not address patients without visible evidence of macular degeneration, nor did it deal with family members of patients with AMD and the role of prophylaxis. Unlike the dry eye studies that used several formulations for therapies, the AREDS study had one specific design. This included vitamin C, vitamin E, Beta-Carotene, Zinc and Copper all in doses that exceed typical daily recommendations.

The study demonstrated that a formulation that includes anti-oxidents and Zinc brings about a 25% decrease in the incidence of significant vision loss in patients with existent macular degeneration. One out of every four patients with AMD will not suffer the severe loss of vision that accompanies the advanced state of this disease. Approximately 300,000 people would be affected if clinicians incorporated this type of therapy.

While the data supporting use of AREDS therapy is compelling, nutraceuticals have the same potential for side effects as traditional medical intervention. Beta-carotene has been associated with an increased risk of pulmonary cancer in smokers and is contraindicated in individuals with a current or recent (within 10 years) use of tobacco. Vitamin E decreases platelet function and can have significant synergy with anti-platelet agents such as Coumadin, Heparin and other anti-coagulents. It should not be prescribed in individuals on therapy with these agents. Additionally, it should be discontinued prior to any surgery that involves vascular tissue. High dose Zinc (greater than 100 mg /day) potentially increases rates of prostate cancer in men when taken for long periods.

No discussion of nutraceuticals is complete without comment on the use in prophylaxis for AMD. Many studies show that agents such as Lutein and Zeaxanthin may have maculoprotective capacity. In most of these studies though, the duration of the trial or the construction of the clinical process does not allow for a definitive statement as to efficacy. It's going to take a much longer review to understand the full impact of these and other agents, but the future looks good for prophylaxis.

The next big thing

Optometry is on the brink of a new era in clinical therapy with the introduction of therapeutic nutraceuticals and the remarkable increase in the number of individuals in the 60-and-older age group who are typically associated with chronic disease states. Twenty-five years ago, therapeutics irrevocably changed our profession and moved optometry into a new era. Nutraceuticals, while still in their infancy, hold the same potential to expand and enrich us and our patients.

Dr. Thimons is a nationally and internationally acclaimed speaker and serves as medical director at Ophthalmic Consultants. He was awarded Optometry's Top Educator in 1999.

 



Optometric Management, Issue: June 2004