AMD: Focusing on the Facts
 
 
rxPassport Pharmacy Newsletter
 
January 2015
 
 
Are evidence-based eye vitamins hidden in your blind spot?
 
Meet Our Patient
 
Rose (65 yo) has just been told by her eye doctor to start taking “eye vitamins” to prevent the progression of her age-related macular degeneration (AMD). After examining the labels of several different products, she wants your advice about one that contains the “AREDS” formula plus omega-3.
 
Her medication history includes:
 
Atorvastatin for high cholesterol
Sumatriptan as needed for migraine
Calcium and vitamin D for bone health
Multivitamin for general health
 
She also quit smoking 25 years ago.
 
Which eye supplement product would you recommend for Rose?
 
A. AREDS formula
B. AREDS formula minus beta carotene
C. AREDS formula + omega-3
D. AREDS2 formula
E. AREDS2 formula + omega-3
AMD: Focusing on the Facts
 
The impact of AMD is insidiously and rapidly climbing: As the leading cause of visual impairment in the aging population, AMD will become the primary driver of Canada’s vision loss epidemic as the number of adults over 65 years doubles within the near future1,2,3.
 
Did you know?
 
• AMD is the leading cause of blindness in individuals over the age of 50 in Canada1 .
 
• It exists in two forms: the earlier “dry” (nonexudative, atrophic) stage and the advanced “wet” (exudative, neovascular) stage4.
 
• It results from the progressive breakdown of macular cells, leading to the loss of central vision4.
 
• Vision loss can have a significant impact on morbidity and mortality, leading to the loss of independence, mental illness, and an increased risk of falling and premature death1.
 
What is AREDS?
 
The two landmark Age-Related Eye Disease Study (AREDS) trials have provided the most valuable evidence about the role of nutrition in preventing AMD progression. AREDS1 examined the impact of high-dose antioxidants and minerals on the progression of macular degeneration. AREDS2 evaluated how the original AREDS formula could be improved.
 
The key findings from both trials are summarized in Table 1.
 
Table 1. Key Findings from the AREDS1 and AREDS2 Trials5,6
AREDS1 AREDS2
AREDS formulaa is superior to placebo: The AREDS formula significantly reduced the progression of AMD by 25% compared to placebo in patients with:
 
1. Intermediate dry AMD in one/both eyes
 
2. Advanced dry AMD in one eye only compared to placebo5.
AREDS2 formulab is superior to the AREDS formula: The AREDS2 formula significantly reduced the progression of AMD by 18% compared to the AREDS formula in patients with:
 
1. Intermediate dry AMD in one/both eyes
 
2. Advanced dry AMD in one eye only6.
 
Beta carotene is associated with an increased risk of lung cancer mainly in previous smokers: The risk of lung cancer was 2.1% vs 0.9% in the beta carotene vs beta carotene-free groups; 91% of patients were previous smokers in both groups6.
 
Omega-3 + AREDS formula is non-inferior to AREDS formula alone: Inclusion of omega-3 does NOT provide additional benefit in reducing AMD progression6.
 
a. AREDS formula = vitamin C 500 mg, vitamin E 400 IU, beta carotene 15 mg, zinc 80 mg, copper 2 mg
 
b. AREDS2 formula = vitamin C 500 mg, vitamin E 400 IU, lutein 10 mg, zeaxanthin 2 mg, zinc 80 mg, copper 2 mg
 
The most important take-home message from the AREDS trials is that not all eye-supplements are equal and for everyone. The benefits of high-dose eye supplements are restricted to:
 
Specific products (i.e., those that contain ingredients and doses validated in the AREDS trials)
 
Specific populations (i.e., those patients with intermediate dry AMD in one/both eyes AND patients with advanced dry AMD in one eye only).
 
Pharmacists are encouraged to review the AREDS trials, which are both available online and free to view:
 
AREDS1
 
AREDS2
 
Did you know?
 
Although numerous eye supplement products have sprung onto the shelves of pharmacies with various claims to support eye health, a recent study revealed that top-selling eye vitamins DO NOT contain the ingredients and/or doses supported by the AREDS trials7.
 
For patients who wish to protect their eyes against eye-related diseases including AMD, continue to recommend nonpharmacological strategies instead such as:
 
Smoking cessation (#1 risk reduction strategy!)1
 
Optimization of cardiovascular health
 
Diet rich in dark, leafy greens
 
UV-protective sunglasses
Redefining the danger of beta carotene
 
AREDS2 investigators affirmed the danger of beta carotene in former smokers based on the results that 91% of those who developed lung cancer after using beta carotene previously smoked6. However, beta carotene is potentially unsafe in all individuals given that 9% of individuals who developed lung cancer in the trial were not former smokers6,8. This means:
 
Previous smokers, no matter how remote their smoking history, should not receive beta carotene-containing products due to a potentially persistent risk of lung cancer irrelevant to the date of cessation.
 
Individuals without a history of smoking should likely not receive beta carotene-containing products due to the small and undefined risk of lung cancer in this population.
 
 
Gene-directed therapy on the horizon
 
A recent retrospective analysis of the AREDS1 trial arrived to a conclusion with the potential to change eye nutrition therapy: an individual’s genotype is correlated to the efficacy of the supplement’s composition. Patients with specific permutations of two genes, CFH and ARMS2, may actually respond better to the antioxidant-only formulation or to zinc alone9.
 
Clinical Practice Tip!
 
Discuss fall prevention strategies with patients who have already experienced some degree of vision loss. For more information on how to prevent falls, visit our previous e-newsletter.
Back to Our Patient
 
You steer Rose toward a product that contains the beta carotene-free AREDS2 formula without the added omega-3. You explain that:
 
Eye supplements should be taken on a daily basis, indefinitely.
 
Nonpharmacological strategies, such as monitoring vision at home with an Amsler grid, can also help detect and prevent advanced AMD progression.
 
 
 
Kristen
 
By Kristen Husack, PharmD Student
 
With appreciation to Mike Boivin
 
In this issue
 
Meet Our Patient
 
AMD: Focusing on the Facts
 
What is AREDS?
 
Redefining the danger of beta carotene
 
Gene-directed therapy on the horizon
 
Back to Our Patient
 
Interactive Poll
 
Resources
 
References
 
Pharmacy Student Blog
 
Interactive Poll
 
Q: How often do you recommend or discuss vitamins for AMD and vision-related conditions?
 
At least once a week
 
About once or twice a month
 
About once or twice every 3 months
 
About once or twice a year
 
Very rarely asked about these vitamins
 
 
Q: After reading this newsletter, how confident are you in making evidence-based eye vitamin recommendations?
 
Very confident
 
Confident
 
Not confident
 
 
Resources
 
National Eye Institute
 
AREDS1 Trial
 
AREDS2 Trial
 
References
 
1. CNIB and the Canadian Ophthalmological Society. The cost of vision loss in Canada: summary report. 2008 [cited 2015 Jan 10].
 
2. 2. Canadian National Institute for the Blind [Internet]. Fast facts about vision loss. 1996-2014 [cited 2014 Dec 19]. View source.
 
3. Statistics Canada. Population projections for Canada, provinces and territories: 2009 to 2036. www.statscan.com. 2010 Jun [cited 2014 Apr 4]. View source.
 
4. de Jong P. Age-related macular degeneration. N Engl J Med [Internet]. 2006 Oct [cited 2015 January 10];355:1474-1485.
 
5. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose vitamin supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss; AREDS Report No. 8. Arch Ophthalmol [Internet]. 2001 [cited 2014 Dec 21];119(10):1417-1436. View Source
 
6. Age-Related Eye Disease Study Research Group. Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: The age-related eye disease study 2 (AREDS2) randomized clinical trial. JAMA [Internet]. 2013 [cited 2014 Dec 21];309(19):2005-2015. View Source
 
7. Yong J, Scott I, Greenberg P. Ocular nutritional supplements: Are their ingredients and manufacturers' claims evidence-based? Ophthalmology [Internet]. 2014 Nov [cited 2014 Dec 19]. Published online. View source.
 
8. Potter M. Age-related macular degeneration. e-Therapeutics [Internet]. 2015 [cited 2015 Jan 3].
 
9. Awh C, Lane A, Hawken S, Zanke B, Kim I. CFH and ARMS2 genetic polymorphisms predict response to antioxidants and zinc in patients with age-related macular degeneration. Ophthalmology. 2013 Nov [cited 2014 Dec 21];120(11):2317-2.
 
 
 
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