Purpose: Macular carotenoid pigments composed of lutein and zeaxanthin are thought to affect the development of age-related maculopathy (ARM). Macular carotenoid levels were measured in normal Japanese subjects and Japanese patients with ARM.
Design: Observational case-control series.
Participants: One hundred normal eyes of 100 normal subjects and 187 eyes of 97 patients with ARM; all were Japanese. The definitions of early ARM and late ARM (exudative age-related macular degeneration [AMD] and dry AMD) were used according to an accepted international classification system.
Methods: Macular carotenoid levels were measured using resonance Raman spectroscopy.
Main outcome measure: Raman signal intensity generated from carbon-carbon double bond vibrations of lutein and zeaxanthin.
Results: The mean (+/-standard deviation [SD]) macular carotenoid level in normal subjects was 1471+/-540 Raman counts. The macular carotenoid levels in normal subjects declined with age. The mean macular carotenoid level was 620+/-204 (+/-SD) in eyes with early ARM and 427+/-283 (+/-SD) in eyes with late ARM (equal to AMD). The macular carotenoid levels of early ARM and AMD were significantly lower than those in normal subjects older than 60 years (1100+/-340 [+/-SD]). No difference was revealed in carotenoid levels by the severity for ARM, type of AMD (exudative, atrophic, and disciform scar), or types of choroidal neovascularization (classic, minimally classic, occult, polypoidal choroidal vasculopathy), although small numbers in some groups weakened statistical power. Macular carotenoid levels were affected by the severity of macular disease in the opposing eye. The average for normal eyes where AMD was found in the opposite eye was significantly lower than that of normal eyes in the absence of AMD in the opposite eye (i.e., healthy volunteers older than 60 years).
Conclusions: Macular carotenoids decreased even in older healthy individuals. The ARM patients showed lower macular carotenoid levels than healthy people. Low macular carotenoid levels may be one of the risk factors of progression in ARM.