Study confirms benefit of supplements for slowing age-related macular degeneration – Neuroscience News

Overview: The AREDS2 dietary supplement that replaces the antioxidants lutein and zeaxanthin with beta-carotene reduces the risk of age-related macular degeneration progression, a new study reveals.

Source: NIH

The Age-Related Eye Disease Studies (AREDS and AREDS2) found that dietary supplements may slow the progression of age-related macular degeneration (AMD), the most common cause of blindness in older Americans. In a new report, scientists analyzed 10 years of AREDS2 data.

They show that the AREDS2 formula, which replaces the antioxidants lutein and zeaxanthin with beta-carotene, not only reduces the risk of beta-carotene lung cancer, but is also more effective at reducing the risk of AMD progression, compared to the original. formula.

A report on the study, funded by the National Institutes of Health, published in JAMA Ophthalmology.

“Because beta-carotene increased lung cancer risk for current smokers in two NIH-supported studies, our goal with AREDS2 was to create an equally effective supplement formula that can be used by anyone, whether they smoke or not,” Emily said. Chew. , MD, director of the Division of Epidemiology and Clinical Application at the National Eye Institute (NEI), and lead author of the study report.

“These 10-year data confirm that the new formula is not only safer, but even better at slowing AMD progression.”

AMD is a degenerative disease of the retina, the light-sensitive tissue at the back of the eye. Progressive death of retinal cells in the macula, the part of the retina that provides clear central vision, eventually leads to blindness. Treatment can slow or reverse vision loss; however, there is no cure for AMD.

The original AREDS study, launched in 1996, showed that a dietary supplement formulation (500 mg vitamin C, 400 international units vitamin E, 2 mg copper, 80 mg zinc, and 15 mg beta-carotene) could significantly slow the progression of AMD from moderate to late illness.

However, two concurrent studies also found that people who smoked and took beta-carotene had a significantly higher than expected risk of lung cancer.

In AREDS2, started in 2006, Chew and colleagues compared the beta-carotene formulation to a formulation containing 10 mg lutein and 2 mg zeaxanthin. Like beta-carotene, lutein and zeaxanthin are antioxidants with activity in the retina. The beta-carotene-containing formation was only given to participants who had never smoked or had quit smoking.

At the end of the five-year AREDS2 study period, the researchers concluded that lutein and zeaxanthin did not increase the risk of lung cancer and that the new formation could reduce the risk of AMD progression by about 26%.

After the completion of the five-year study period, the study participants were all offered the final AREDS2 formation containing lutein and zeaxanthin instead of beta-carotene.

In this new report, the researchers followed 3,883 of the original 4,203 AREDS2 participants for an additional five years from the end of the AREDS2 study in 2011, gathering information about whether their AMD had progressed to late disease and whether they had been diagnosed with AMD. lung cancer.

Although all participants had switched to the lutein-zeaxanthin formula after the end of the study period, the follow-up study continued to show that beta-carotene increased the risk of lung cancer for people who had once smoked nearly double that.

There was no increased risk of lung cancer in those receiving lutein/zeaxanthin.

In addition, the group originally assigned to receive lutein/zeaxanthin had an additional 20% lower risk of progression to late AMD after 10 years compared to those originally assigned to receive beta-carotene.

“These results confirmed that switching our formula from beta-carotene to lutein and zeaxanthin was the right choice,” Chew says.

Financing: The study was funded by the NEI Intramural Program (EY000546) and through contracts (AREDS2 contract HHS-N-260-2005-00007-C; ADB contract NO1-EY-5-0007; AREDS Contract NOI-EY-0-2127, and contract HHS-N-263-2013-00005-C).

The AREDS2 contracts were supported by the NIH Office of Dietary Office of Dietary Supplements, the National Center for Complementary and Integrative Health, the National Institute on Aging, the National Heart, Lung and Blood Institute, and the National Institute of Neurological Disorders and Stroke.

The study took place at the NIH Clinical Center.

About this age-related research news on macular degeneration

Author: Lesley Earl
Source: NIH
Contact: Lesley Earl – NIHO
Image: The image is in the public domain

Original research: Closed access.
†Long-term results of adding lutein/zeaxanthin and ω-3 fatty acids to the AREDS supplements on age-related macular degeneration progressionby Chew EY, et al. JAMA Ophthalmology

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Abstract

Long-term results of adding lutein/zeaxanthin and ω-3 fatty acids to the AREDS supplements on age-related macular degeneration progression

Interest

Following the Age-Related Eye Disease Study 2 (AREDS2) study, the beta-carotene component was replaced with lutein/zeaxanthin for the development of the revised AREDS supplement. However, it is not known whether the increased risk of lung cancer observed in those assigned beta-carotene persists after the completion of the AREDS2 study and whether there is a benefit of adding lutein/zeaxanthin to the original AREDS supplement that can be observed with prolonged use. follow up.

Objective

To assess the 10-year risk of developing lung cancer and late age-related macular degeneration (AMD).

Design, setting and participants

This was a multicenter epidemiological follow-up study of the AREDS2 clinical trial, conducted from December 1, 2012 to December 31, 2018. The analysis included participants with bilateral or unilateral intermediate AMD for an additional 5 years after the clinical trial. Eyes/participants were censored at the time of late AMD development, death, or loss for follow-up. Data was analyzed from November 2019 to March 2022.

interventions

During the clinical trial, participants were randomly assigned primarily to lutein/zeaxanthin and/or ω-3 fatty acids or placebo and secondarily to no beta-carotene versus beta-carotene and low versus high doses of zinc. In the epidemiological follow-up study, all participants received AREDS2 supplements containing lutein/zeaxanthin, vitamins C and E, and zinc plus copper. Results were assessed on 6 months of telephone conversations. Analyzes of AMD progression and lung cancer development were performed using proportional risk regression and logistic regression, respectively.

Main results and measures

Self-reported lung cancer and late AMD validated with medical records.

Results

This study included 3882 participants (mean [SD] baseline age, 72.0 [7.7] year; 2240 women [57.7%]) and 6351 eyes. After 10 years, the odds ratio (OR) of having lung cancer was 1.82 (95% CI, 1.06-3.12; p= 0.02) for those randomly assigned to beta-carotene and 1.15 (95% CI, 0.79-1.66; p= 0.46) for lutein/zeaxanthin.

The hazard ratio (HR) for progression to late AMD, comparing lutein/zeaxanthin to no lutein/zeaxanthin, was 0.91 (95% CI, 0.84-0.99; p= 0.02) and comparing ω-3 fatty acids without ω-3 fatty acids was 1.01 (95% CI, 0.93-1.09; p= .91).

When the analysis of major effects of lutein/zeaxanthin was limited to those randomly assigned to beta-carotene, the HR was 0.80 (95% CI 0.68-0.92; p= .002).

A direct analysis of lutein/zeaxanthin versus beta-carotene showed that the HR for late AMD was 0.85 (95% CI: 0.73-0.98; p= .02). The HR for low versus high zinc was 1.04 (95% CI, 0.94-1.14; p= 0.49) and the HR for no beta carotene versus beta carotene was 1.04 (95% CI, 0.94-1.15; p= .48).

Conclusions and relevance

The results of this long-term epidemiological follow-up study of the AREDS2 cohort suggest that lutein/zeaxanthin was a suitable replacement for beta-carotene in AREDS2 supplements. The use of beta-carotene almost doubled the risk of lung cancer, while there was no statistically significant increased risk with lutein/zeaxanthin. Compared to beta-carotene, lutein/zeaxanthin had a potentially beneficial association with late AMD progression.