Xanthophyll Carotenoid Intake, Plasma Levels, and Retinal Visualization in Aging and Age-Related Macular...

The purpose of this study was to determine cross-sectional associations among intake of xanthophyll carotenoids lutein and zeaxanthin (L&Z), plasma L&Z, and two wavelength autofluorescence (2WAF) retinal imaging in aging and age-related macular degeneration (AMD).

Adults ≥63 years old from a comprehensive ophthalmology clinic underwent assessments: macular health (Age-Related Eye Disease Study [AREDS] 9-step); self-reported L&Z intake from diet (LZQ Food Frequency Questionnaire) and supplements; total intake; macular pigment optical volume (MPOV; in 2WAF); non-fasting plasma L&Z; and HDL and LDL cholesterol. Associations were adjusted for age and HDL/LDL.

We studied 369 persons (74 ± 5.8 years, 60% women, 89% White, 62% never-smoker, and 23% supplement use) and 369 eyes (48.4% healthy, 26.0% early AMD [eAMD], and 25.2% intermediate AMD [iAMD]). Diagnostic groups differed in supplement users (10%, 17%, and 56%), total L&Z intake (5.3 ± 6.4, 5.5 ± 5.4, and 11.0 ± 8.3 mg/d, P < 0.01), and MPOV (1.04 ± 0.46, 1.02 ± 0.52, and 1.33 ± 0.61). Groups did not differ in dietary intake (3.8 ± 4.5, 3.4 ± 3.2, and 3.7 ± 3.8 mg/d), plasma HDL, or HDL/LDL. Associations were strong between plasma L&Z and MPOV (r = 0.41-0.67, P < 0.01); moderate between total intake and plasma L&Z (Spearman r = 0.29-0.50, P < 0.01); weaker but significant for L&Z intake, and MPOV (r = 0.22-0.30, P < 0.01) of 3-mm-diameter macula lutea only, for eAMD and iAMD.

In a large US sample, we assess for the first time L&Z intake from diet and supplements and determined the relative strength of correlations among intake, plasma, and retinal xanthophylls. We replicate our earlier finding of elevated retinal and plasma L&Z in iAMD. LZQ and 2WAF are suitable outcome measures for future interventions that directly test the impact of L&Z on AMD onset and progression.