Abstract
Purpose: :
To assess the association of age-related macular degeneration (AMD) with cognitive function and depression using baseline data from AREDS2.
Methods: :
AREDS2 participants were approached at baseline to participate in the AREDS2 Cognitive Function Substudy. The AREDS2 Cognitive Function Battery is administered via telephone and includes 6 neuropsychological tests measuring performance in several cognitive domains and a depression scale. Clinical "cut-points" or scores below 1.5 standard deviations of the norm, were used to define reduced cognitive function for the individual tests. If these normative data were not available reduced cognitive function was defined as a score below the 5th percentile for the AREDS2 cohort. Overall reduced cognitive function on the AREDS2 Battery was defined as reduced cognitive function on 3 or more of the tests. Participants without advanced AMD in one eye were classified into one of 5 groups based on the number of ocular risk factors (0 to 4) for the development of advanced AMD (AREDS Simple Scale). Because the majority of the participants in AREDS2 had at least 2 risk factors we combined simple scale scores 0, 1, and 2. An additional category was created consisting of the participants with advanced AMD (neovascular AMD or central geographic atrophy) in one eye for a total of 4 AMD status categories. Logistic regression models were used to assess the associations of the cognition and AMD risk.
Results: :
The Battery was administered to 3,336 participants aged 50 to 85 years (median: 74 years). Participants with 4 ocular risk factors had significantly higher odds of reduced cognitive function on the TICS (odds ratio [OR]: 1.56; 95% CI: 1.04 - 2.34 compared to participants with mild AMD after adjustment for age, gender, education, race, depression and self-reported hypertension, congestive heart failure, coronary heart disease, angina, MI, heart attack, or stroke. Comparison of participants with unilateral advanced AMD to those with mild AMD produced the same relationships for outcomes on the TICS (OR=2.00; 95% CI: 1.35 - 2.96), the depression scale (OR: 1.33; 95% CI: 1.06 - 1.67), and overall reduced cognitive function on the AREDS2 battery (OR: 1.91; 95% CI: 1.00 - 3.65).
Conclusions: :
These data suggest an association between cognitive function and depression with AMD status and risk factors for progression to advanced AMD.
Clinical Trial: :
www.clinicaltrials.gov NCT00345176
Keywords: age-related macular degeneration • aging • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology