Abstract
Purpose :
Advanced glycation endproducts (AGEs) have been found to accumulate in drusen and Bruch’s membrane. Higher levels of skin autofluorescence (SIF), a noninvasive marker for measuring systemic accumulation of AGEs, have been found by others to be associated with neovascular AMD. We examined the cross-sectional relationships of SIF to AMD to show whether SIF is associated with the prevalence and severity of AMD.
Methods :
Fundus photography and SIF measurement data came from 963 persons (out of a total of 1183), aged 68 to 102 years, participating in the 25-year long follow-up examinations of the population-based Beaver Dam Eye Study (BDES). SIF was measured on the underside of the left forearm near the elbow with the SCOUT DS® skin fluorescence spectrometer (VeraLight, Inc., Albuquerque, NM). Two representative SIF measures were used for these analyses: SIF01 excited by an LED centered at 375 nm with correction factors Kx=0.6 and Km=0.2, and SIF15 excited by an LED centered at 456 nm with correction factors Kx=0.4 and Km=0.9. In addition, a white LED was used to measure skin reflectance over the 435-655 nm region, allowing intrinsic correction of individual subjects’ measured fluorescence for variation in skin tone. Age-related macular degeneration was assessed from digital 30° color fundus photographs using the Wisconsin Age-Related Maculopathy Grading system. Severity of AMD was defined by the 3-Continent AMD severity scale. Analyses were done for each eye with a generalized estimating equations adjustment for the correlation between the eyes of a person.
Results :
The 963 persons contributed 1832 eye records for analyses. Early AMD was present in 18% and late AMD in 4% of the eyes. Adjusting for age, sex, diabetes status, smoking status and history of cardiovascular disease, there were no associations of SIF01 (odds ratio per 1 SD difference on the log scale, 95% CI and p-value) (1.00, 0.83 to 1.20, p=0.99) or SIF15 (1.04, 0.86 to 1.27, p=0.66) with early AMD and no associations of SIF01 (1.12, 0.83 to 1.50, p=0.46) or SIF15 (1.10, 0.71 to 1.52, p=0.84) with late AMD.
Conclusions :
SIF was not cross-sectionally associated with AMD when adjusting for important age and cardiovascular confounders. This may reflect that there is no causal relationship of AGEs and its correlates with AMD.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.