Predictors of macular pigment and contrast threshold in normolipemic subjects aged 45-65

Abstract Objective: The dietary carotenoids lutein and zeaxanthin are transported in the bloodstream by lipoproteins and selectively captured in the retina where they constitute macular pigment. There are no lutein and zeaxanthin dietary intake recommendations nor desired blood/tissue concentrations for the general population. The aim of this study was to determine the lutein and zeaxanthin dietary intake, their serum concentrations, lipid profile, macular pigment optical density (MPOD) and the contrast sensitivity (CT), as visual outcome in normolipemic subjects age 45-65 (n=101). Methods: MPOD, L and Z in serum and dietary intake were determined using heterochromatic flicker photometry, high-performance liquid chromatography and 3-day food records. CT was measured with the CGT-1000 Contrast Glaretester at six stimulus sizes, with and without glare. Results: Lutein and zeaxanthin serum concentrations (median): 0.361 and 0.078 µmol/L. Lutein+zeaxanthin intake: 1.1 mg/d (median). MPOD: 0.34 du. Lutein+zeaxanthin intake correlates with their serum concentrations (ρ=0.333, p =0.001), which in turn correlates with MPOD (ρ=0.229, p =0.000) and with the fruit and vegetable consumption (ρ=0.202, p =0.001), but not with the lutein+zeaxanthin dietary intake. HDL-cholesterol correlated with lutein+zeaxanthin serum (ρ=0.253, p =0.000) and with CT under glare conditions (ρ range: 0.016–0.160). MPOD predictors: serum lutein+zeaxanthin, lutein+zeaxanthin/HDL-cholesterol and HDL-cholesterol (R 2 =15.9%). CT predictors: MPOD and sex (β coefficients ranges: -0.950,-0.392; -0.134,-0.393, respectively). Conclusion: There were correlations at all points in time in this sequence between lutein+zeaxanthin intake and the visual outcome and, HDL-cholesterol played a relevant role.