The AREDS study group has released the results of AREDS 2 and recommended the continued use of the original AREDS formulation, with beta-carotene removed and replaced by lutein/zeaxanthin. The use of a fish oil supplement could not be recommended based on these results.
The Macular Disease Foundation (MDF) has welcomed these initial results, which confirm the advice the Foundation has been offering people with age related macular degeneration for some years.
The results were presented by Dr. Emily Chew, Deputy Director of the prestigious National Eye Institute (NEI) in the United States, on 5 May at the Association for Research in Vision and Ophthalmology (ARVO) conference in Seattle.
Julie Heraghty, CEO of the Macular Disease Foundation said the study design and conclusions were complex.
The results of the AREDS2 trial are a disappointing surprise to many experts…
Based on the findings of the original AREDS study, the AREDS2 study population was limited to people with either large drusen in both eyes, or late stage disease in one eye and large drusen in the other. People with early disease or late disease in both eyes were not included in the study.
The study was conducted in a population that was, on average, ten years older than in the original AREDS study, and at a higher risk of disease progression. The AREDS2 study population was also better nourished, meaning that it would be more difficult to demonstrate a benefit of supplementation. If a benefit could be demonstrated, it was therefore likely to be important. Patients were followed for an average of 4.9 years.
A disappointing surprise
Speaking of the findings, Dr. Simon Chen, a Sydney based retinal specialist said, “The results of the AREDS2 trial are a disappointing surprise to many experts who were hoping to see a benefit from taking omega-3 fatty acids in slowing the progression of AMD. Unfortunately, the trial failed to show any positive effect from taking omega-3 fatty acid supplements in slowing disease progression over the five-year duration of the study.”
Julie Heraghty, CEO of the Macular Disease Foundation said the Foundation will continue to recommend people eat fish two to three times a week because of the general health benefits fish can provide. Additionally, she said several other large population studies have consistently shown consumption of actual fish significantly reduces the risk of AMD.
Another key finding from the study was that the addition of lutein/zeaxanthin provided a small benefit, which was significantly greater for people who had the lowest intake of lutein in their regular diet.
In a sub-group analysis, it was also shown that when beta-carotene was removed from the original formulation, and replaced with lutein/zeaxanthin, there was an 18 per cent additional reduction in the risk of progression to late stage AMD.
The study made a clear recommendationto remove beta-carotene from the supplement, because it did not contribute to efficacy, increased the risk of lung cancer, especially in people who smoke or previously smoked; and led to a reduced absorption of lutein/zeaxanthin.
The use of a lower dose of zinc (25 mg/day) did not appear to provide any benefit over the original dose (80 mg). It did not have a lower rate of side effects and there was a statistically non-significant trend to reduced efficacy, compared to the original, higher dose. It should also be noted that the safety of the original, higher dose was recently confirmed with the publication of the 10 year follow-up of the original AREDS trial.
Ms. Heraghty said now the results of AREDS 2 have been released, MDF will work with its medical committee and national research advisor Professor Paul Mitchell to review its nutrition and supplements guide.
