Abstract
Purpose: :
Evaluate whether dietary supplementation with the carotenoid zeaxanthin (Z) raises macula pigment optical density (MP) and has unique visual benefits for patients with atrophic early AMD having visual symptoms but lower risk NEI / AREDS characteristics.
Methods: :
1 year, n=60, 4 visit, prospective RCT (randomized controlled clinical trial) of patients (74.9 SD 10 y) with mild / moderate AMD randomly assigned to one of 2 dietary supplement carotenoid pigment intervention groups: 8mg Z (n=25) & 8mg Z / 9mg Lutein L ( n=25) or to a 9 mg L (faux - placebo - control group n=10). Analysis by Bartlett’s Test for equal variance, 3 way repeated factors ANOVA and independent T test (P < 0.05) for variance & between / within group differences. Estimated HFF 1° MP, foveal shape discrimination (RFSW) and Kinetic 10° yellow visual fields (KVF) were obtained serially.
Results: :
90% of subjects completed > 2 visits w an initial AREDS report #18 retinopathy score of 1.4 (1.0 SD) /4.0 and pill intake compliance of 96%. There were no inter-group differences in 3 major AMD risk factors: Age, Smoking, BMI as well as disease duration & VFQ25 composite score differences. Randomization resulted in equal MP variance; MP rising in each of the 3 groups from 0.33 du (0.17 SD) @ baseline to 0.51du (0.18 SD) @ 12m but no between group differences (ANOVA; P=0.47). However, the Z group had distinctly better RFSW @12m improving from (0.97 to 0.57, T =0.06, 1 tail) compared with L. Also, a larger % of Z patients experienced a serial KVF partial/ complete clearing of their central scotoma (54%) compared with the L group (45%).
Conclusions: :
Z induced MP elevation mirrored that of L. Unique visual benefits for patients with AMD include better shape discrimination and possibly better central scotoma resolution.
Clinical Trial: :
www.clinicaltrials.gov 2007-11-27
Keywords: age-related macular degeneration • carotenoids/carotenoid binding proteins • shape, form, contour, object perception