The relationship between lutein and zeaxanthin intake and change in macular pigment in the Second Carotenoids in Age-Related Eye Disease (CAREDS 2) study

Abstract

Purpose : Macular pigment (MP) is a retinal accumulation of lutein and zeaxanthins (L/Z). MP filters blue light, and serves antioxidant and anti-inflammatory roles in the retina. Higher MP may reduce risk for age-related macular degeneration, and improve visual performance. Hence, maintaining or increasing MP as we age may be beneficial. Little is known regarding change in MP over a decade or more. We aim to quantify change in MP over 15 years in a cohort of older women, and to describe the relationship with total L/Z intake, and intake from diet and supplements separately.

Methods : 374 women (age 69-98) completed MP testing at baseline (2001-2004) and CAREDS 2 (2016-October, 2017) using heterochromatic flicker photometry. MP optical density (MPOD) measured at 0.5 degrees from the foveal center (with a reference measure at 7 degrees) is reported here. L/Z from diet and supplements was estimated via questionnaires. The relationship between MP change and total L/Z, dietary L/Z, and L/Z from supplements was assessed using linear regression, controlling for age, baseline MPOD, and calories. We also evaluated possible modification by MPOD at baseline or central adiposity (assessed via waist circumference), as these factors may limit accumulation of L/Z.

Results : We observed a mean [SE] increase of 0.15 [0.01] optical density units (39%) since baseline (P < .01), which may be partly explained by greater total L/Z intake. Consuming ≥ 10 mg/day total L/Z was associated with greater MPOD change (P = .05), although no significant linear relationship was seen. The association was driven by L/Z from supplements rather than diet. Consuming L/Z supplements ≥ 1 mg/day was strongly associated with MP change (P < .01). This was not modified by waist circumference, but was modified by baseline MPOD. Supplement users in the highest MPOD quartile (>0.52 OD units) had a lower mean [SE] change, compared with those in the lowest 3 quartiles (0.02 [0.06] vs. 0.27 [0.04], respectively; P-interaction < 0.01).

Conclusions : Despite early observations of declines in MPOD with age in cross-sectional studies, results in this prospective study suggest that MP can increase over time in older women and that supplement use and total L/Z intakes ≥ 10 mg daily promote accrual of MP, particularly in women with lower baseline levels.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.