A Prospective Study of Neuro-Cognitive Enhancement with Carotenoids in Elderly Adult Males with Early Age Related Macular Degeneration

Abstract

Background: Diets rich in carotenoids may reduce cognitive impairment. Little is known about dietary zeaxanthin. Objective: Evaluate zeaxanthin carotenoid supplementation against change in cognitive status. Methods: American Psychological Association (APA) certified cognitive evaluation from the Zeaxanthin and Vision Function Study (USFDA Investigative New DrugIND#78,973), a 1 year prospective randomized controlled trial (RCT) of elderly males with mild age related macular degeneration. Neurocognitive testing Repeatable Battery for the Assessment of Neuropsychological Status Update RBANS and Trail Making A & B. Subjects evaluated at baseline and 1 year after dietary isomer RR zeaxanthin (8 mg/d) alone or combined with lutein (9 mg/d) using one way ANOVA, (P<0.05) and T testing. Results: n=50 subjects completed both study visits. Delayed memory in the zeaxanthin group improved from RBANS score of 91.8 (SD 16) to 99.4 (SD 12), P = 0.04.  Conclusions: Zeaxanthin, typically minimally present in the US diet, may nonetheless be important in the context of emerging relationships in primates between dietary xanthophyll carotenoids and cognitive function. Additional larger scale RCTs is indicated to investigate the clinical utility of this carotenoid in nutritional neuroscience.