Abstract
Purpose :
Recent investigations have demonstrated that macular pigment (MP is lower in glaucomatous eyes. MP exhibits specific biological qualities which may confer neuro-protective and functional benefits in glaucoma. The European Nutrition In Glaucoma Management (ENIGMA) trial was designed to evaluate, for the first time, the MP response to supplementation in glaucoma.
Methods :
ENIGMA (NCT04460365) comprised a randomized, placebo controlled, double masked trial. Individuals with open angle glaucoma, VA < 0.3, no other ocular disease, and no history of dementia were eligible for inclusion. Participants were randomized in a 2:1 ratio to receive a dietary carotenoid supplement [10mg lutein (L), 10mg meso-zeaxanthin (meso-Z) and 2mg zeaxanthin (Z)], or placebo for 18 months. MPOD was measured at baseline, 6, 12 and 18 months by dual-wavelength autofluorescence using Heidelberg Spectralis.
Results :
62 participants were enrolled, 44 assigned to treatment and 18 to placebo. No baseline differences between groups were observed (P > 0.05 for all -Table 1). Repeated measures ANOVA showed that sqrt MPOD volume differed significantly for the interaction between treatment and time [F(3,111)= 31.718690, p < 0.001] with a significant effect of time [F(3,111)= 71.277135, p < 0.001] and no significant effect of treatment [F(1,37)= 2.642403, p =0.112]. Post hoc tests with Bonferroni correction revealed a significant difference between baseline MPOD and MPOD at each timepoint (6, 12 and 18 months) in the treatment group only (Fig 1). There was a significant difference in MPOD volume between the treatment and placebo group at 12 and 18 months.
Conclusions :
ENIGMA is the first study to demonstrate that MP levels can be augmented in glaucomatous eyes by carotenoid supplementation, which represents an important pre-cursor to any functional or health-related benefits that may accrue. From a neuro-protective perspective, oxidative stress and chronic inflammation are key pathways of tissue damage involved in glaucoma. As potent antioxidant and anti-inflammatory nutrients, L, Z and meso-Z supplementation to increase MPOD might support retinal ganglion cells and confer protection by preventing the pathophysiological cascades of oxidative stress and inflammation in glaucoma.
This is a 2021 ARVO Annual Meeting abstract.