Abstract
Purpose :
To examine the relationship of a marker of oxidative stress, oxidized low-density lipoprotein (ox-LDL), to the incidence of AMD over a 25-year period in the population-based Beaver Dam Eye Study.
Methods :
A total of 3,823 participants aged 43 to 86 years at the beginning of the study (1988-1990) had up to 5 follow-up examinations, at approximately 5-year intervals, over a 25 year period. AMD was assessed using grading of fundus photographs specified by the Wisconsin Age-related Maculopathy Grading System 5 step severity scale defined by the 3-Continent Group. Progression was defined as a 1-step or greater change in the worse eye at the previous exam. Incidence of AMD (level 10 to level 20+) and late AMD (first appearance of level 50) were identified. Ox-LDL was measured in a randomly selected sample of the cohort (n=1712 eligible for incidence analyses) using an ELISA assay from stored specimens available at each examination phase (a total of 4,165 person-visits). Logistic regression with generalized estimating equations to account for correlation between the visits of a person was used.
Results :
The mean (SD) level of oxidized low-density lipoprotein was 74.1 (22.7) U/L. Incidence of AMD was 8.7% (in 2,840 person-visits), incidence of late AMD was 1.1% (in 3,751 person-visits) and progression of AMD was 11.4% (in 3309 person-visits). While adjusting for age and sex, the level of ox-LDL at the beginning of a period was significantly associated with the incidence of AMD (Odds Ratio (OR) per 10 U/L was1.09, 95% Confidence Interval (CI)1.02,1.15, p=.006) but not late AMD (OR 0.99, 95%CI, 0.87-1.13, p=0.91) or the progression of AMD (OR 1.05, 95% CI 1.00,1.10, p=0.06) at the end of a 5-year period. These relationships remained after adjustment for serum total cholesterol, serum HDL cholesterol and history of statin use (data not shown).
Conclusions :
Our findings are compatible with the hypothesis of a relationship between ox-LDL and the incidence of AMD.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.