Psychological and cognitive determinants of vision function in age-related macular degeneration.

OBJECTIVE To investigate the effect of coping strategies, depression, physical health, and cognition on National Eye Institute Visual Function Questionnaire scores obtained at baseline in a sample of older patients with age-related macular degeneration (AMD) enrolled in the Improving Function in AMD Trial, a randomized controlled clinical trial that compares the efficacy of problem-solving therapy with that of supportive therapy to improve vision function in patients with AMD. METHODS Baseline evaluation of 241 older outpatients with advanced AMD who were enrolled in a clinical trial testing the efficacy of a behavioral intervention to improve vision function. Vision function was characterized as an interval-scaled, latent variable of visual ability based on the near-vision subscale of the National Eye Institute Vision Function Questionnaire-25 plus Supplement. RESULTS Visual ability was highly correlated with visual acuity. However, a multivariate model revealed that patient coping strategies and cognitive function contributed to their ability to perform near-vision activities independent of visual acuity. CONCLUSIONS Patients with AMD vary in their coping strategies and cognitive function and in their visual acuity, and that variability determines patients' self-report of vision function. Understanding patient coping mechanisms and cognition may help increase the precision of vision rating scales and suggest new interventions to improve vision function and quality of life in patients with AMD. Trial Registration  clinicaltrials.gov Identifier: NCT00572039.