Tuesday, November 21, 2017

Carotenoid, antioxidant supplementation is associated with improvements in visual function in nonadvanced age-related macular degeneration patients.

The October 2017 issue of Investigative Ophthalmology & Visual Science reported the outcome of a randomized trial which found an increase in macular pigment and improvement in measures of visual function in association with antioxidant supplementation among individuals with nonadvanced age-related macular degeneration (AMD).

The trial included 121 men and women with nonadvanced AMD in one or both eyes. Participants received a daily supplemental formula that provided 10 milligrams (mg) lutein, 2 mg zeaxanthin, 500 mg vitamin C, 400 IU vitamin E, 25 mg zinc, 2 mg copper and 10 mg meso-zeaxanthin, or the same formula minus meso-zeaxanthin for two years. (Meso-zeaxanthin makes up 25% of the eyes’ macular pigment. Lutein converts to meso-zeaxanthin, however, during aging, this conversion process is disrupted, making supplementation advantageous.)

Serum carotenoid levels and macular pigment increased over time in both groups of participants. Subjects also experienced significant improvements in letter contrast sensitivity, assessments of glare disability, average and maximum reading speed, and other visual functions. No participants who received meso-zeaxanthin progressed to advanced AMD during the trial.

"Eye care professionals should be aware of the observed visual benefits afforded to patients with nonadvanced AMD as a result of supplementation with macular carotenoids (and coantioxidants) in the short, medium, and long terms, and the indication for recommending such supplements should no longer be limited to risk reduction for disease progression in the long term,” write authors Kwadwo Owusu Akuffo and colleagues. “Also, and importantly, further augmentation of macular pigment and further improvements in psychophysical function are realized in patients with nonadvanced AMD after 24 months of sustained supplementation, and it may well be that the improvements observed in this study (duration of 24 months) understate the visual improvements that patients can expect."