Abstract
Purpose: :
The Macular Pigment (MP) plays an important antioxidant role and preserves the macula against the damage of UV radiations. Different epidemiological studies have shown that higher levels of dietary carotenoid intake may protect against the progression of Age–Related Macular Degeneration (ARMD), although few data are available regarding the clinical effects of carotenoid and antioxidant supplementation. This study quantifies the MP using Resonance Raman Spectroscopy (RRS) in ARMD patients (AREDS 3 and 4) after a 12 month treatment with carotenoids and antioxidants, compared to a control group.
Methods: :
153 subjects with ARMD (AREDS category 3 and 4) and visual acuity equal or greater than 20/32 (0.3 LogMAR) in at least one eye have been enrolled and randomly divided into two groups: a treatment group (T–ARMD, n=102 patients) who received oral daily supplementation with Vitamin C (180 mg), Vitamin E (30 mg), Zinc (22.5 mg), Copper (1 mg), Lutein (10 mg), Zeaxanthin (1 mg) and Astaxanthin (4 mg) (AZYR SIFI®, Sifi Italy); a control group (C–ARMD, n=44 patients) received no treatment; 7 drop–out. The eye with better visual acuity was considered. Among these we have selected a subgroup of 14 patients (9 belonged to AREDS 3, 5 belonged to AREDS 4; 8 were treated while 6 were controls) for the present ancillary study. In all these patients we measured the MP with RRS, at baseline, 6 months and 12 months after entering the study. RRS has been performed by illuminating the macular area for 0.25 seconds with a 1–mm spot 488–nm, 1.0 mW argon laser. Raman time profile between the groups was analyzed by ANOVA–MR F–test.
Results: :
Patients in the treatment group show a significant increase of the Raman time profile compared to the control group (treated group vs controls Raman Intensity Counts baseline: 753.4+456.5 vs 654.3+283.3; 6 months: 1130.5+595.5 vs 714.2+265.4 ; 12 months: 1128.4+528.3 vs 676.0+435.0; p<0.05). Raman time profile between the treated group and the control group results also significantly different within AREDS category 3 (treated group vs controls baseline: 929.2+447.9 vs 722.5+252.3; 6 months: 1342.0+624.4 vs 636.0+284.0; 12 months: 1240.2+621.0 vs 736.5+513.8; p<0.02).
Conclusions: :
RRS is a rapid, objective and non–invasive method to measure the MP in vivo; it has been shown that RRS macular pigment values reflect the evolution of macular changes in ARMD. This ancillary study with RRS shows that MP may increase after carotenoid supplementation.
Keywords: macular pigment • age-related macular degeneration • carotenoids/carotenoid binding proteins