Abstract
Abstract: :
Purpose:To compare the Macular Pigment Density (MPD) profiles of Normal, Primary Relatives of AMD (PRAMD), and AMD subjects age 50 and over. Methods:Subjects participating in this study were divided into three groups: Normal, AMD, and PRAMD. A total of 119 Eyes (29 Normal, 59 PRAMD and 31 AMD) of 71 subjects (19 Normal, 33 PRAMD and 19 AMD) were included. MPD was measured with Free Viewing Heterochromatic Flicker Photometry (HFP) using test stimuli of 10min, 30min, 1deg, and 2deg eccentricity relative to the foveal center. Four to five measurements were taken per test stimuli and MPD values were normalized to the value obtained with a fifth stimulus corresponding to 7deg eccentricity. Additionally, subjects were asked to complete a nutritional questionnaire. Results:Age range was 50 to 86, with mean ages of 68, 59 and 63 for AMD, PRAMD and Normal, respectively. MPD profile analysis for each group revealed the presence of two subgroups. Subgroup 1 (sub1) had classic MPD profiles with central peaks that decreased exponentially with increasing eccentricity (i.e. MPD at 10min ≷ 30min ≷ 1deg ≷ 2deg). Subgroup 2 (sub2) had MPD profiles with central depressions in which MPD at 10min was less than MPD at 30min. Among the groups 42% of AMDs, 37% of PRAMDs and 31% of Normals belonged to sub2. Mean MPD for sub1 AMDs and PRAMDs was only significantly higher than mean MPD for sub2 AMDs and PRAMDs at 10min (p < 0.003 and p < 0.014, respectively), and mean MPD at 10min for sub1 Normals was higher than sub2 Normals (p < 0.059). No significant differences in mean MPD were found between sub1 AMDs, PRAMDs, and Normals at the four test loci. The same was true for sub2 AMDs, PRAMDs, and Normals except that sub2 AMDs had significantly deeper central mean MPD depressions than sub2 Normals (p < 0.045) when compared to their respective 30min mean MPD values. There were no significant intra-group differences in lutein consumption. However, AMDs consumed significantly more lutein than PRAMDs (p < 0.010), and PRAMDs consumed significantly more than Normals (p < 0.012). Conclusion:The higher percentage of sub2 AMDs (42%) compared to sub2 PRAMDs (37%) and sub2 Normals (31%) suggests that AMDs have the greatest propensity for lower MPD at 10min, followed by PRAMDs. In addition, sub2 AMDs are the most significantly different (p <0.003) than their sub1 counterparts, and, even though AMDs consume the most lutein, sub2 AMDs have the deepest central depressions in mean MPD.
Keywords: 308 age-related macular degeneration • 554 retina • 354 clinical (human) or epidemiologic studies: prevalence/incidence