The association between macular pigment optical density and visual function outcomes: a systematic review and meta-analysis

Objectives To conduct a systematic review and meta-analysis on data related to macular pigment optical density (MPOD) and visual function in adults with healthy eyes. Methods MEDLINE®, Cochrane, and Commonwealth of Agriculture Bureau abstracts databases were searched for English-language publications between 1946 and August 2018. Included studies examined correlation of MPOD and visual function in adults with healthy eyes at all timepoints and all designs, except for case–control, case reports, and reviews. Visual function outcomes of interest included photostress recovery, contrast sensitivity, visual acuity, glare sensitivity/disability, and dark adaptation. Random effects model meta-analyses combined study-level correlation ( r ). Results Twenty-two publications were included. In meta-analysis MPOD was found to be significantly correlated with contrast sensitivity at 30′ (two studies, summary r : 0.37; 95% CI 0.15, 0.56), and at 1° eccentricity with a spatial frequency of 7, 11, and 21 cpd (three studies, summary r : 0.31; 95% CI 0.06, 0.52), with photostress recovery at a 1° eccentricity with a moderate background, 10 cpd, and 16% contrast (two studies, summary r : −0.17; 95% CI −0.31, −0.02), and at 30′ (four studies, summary r : −0.57; 95% CI −0.78, −0.24), and with glare disability at 30′ eccentricity with a log scale at 460 nm (three studies, summary r = 0.47; 95% CI 0.32; 0.59). There were insufficient data for meta-analysis for other visual functions. Conclusions Our review identifies a link between MPOD and visual function with significant correlations with photostress recovery, glare disability, and contrast sensitivity.