Analysis of prospective data from the Eye Adult Changes in Thought study

Abstract

Purpose : As an extension of the central nervous system, the eye provides a window to understand the health of the brain, including dementia development. We present data from the first 216 participants of Eye Adult Changes in Thought (ACT), a community-based, prospective, longitudinal cohort study to evaluate the relationship between retinal imaging features, visual function, and cognitive decline.

Methods : Participants were recruited from the ACT study, which recruits cognitively intact older adults (≥65 years) and follows them until Alzheimer’s disease and dementia development. Each participant underwent visual acuity (VA) and sinusoidal bullseye contrast sensitivity (CS) at 3 and 6 cycles-per-degree (CPD) (M&S Technology, Niles, IL), intraocular pressure (IOP) with iCare TA01i tonometer (iCare, Raleigh, NC), fundus photography/optical coherence tomography (OCT) with Maestro2 (Topcon Medical Systems, Inc., Oakland, NJ), and 3x3 mm and 6x6 mm OCT angiography with PLEX® Elite 9000 (ZEISS, Oberkochen, Germany). Cognition was tested with Cognitive Abilities Screening Instrument (CASI). Descriptive statistics were performed for demographic and clinical factors, baseline visual function, and OCT data. Associations between ophthalmic data and CASI scores were assessed using multivariable linear regression models. Ophthalmic data of the better seeing eye was analyzed.

Results : 216 participants were recruited as of 11/8/2022. Median age was 78 (interquartile range 74-81), and the majority were male (51.4%), white (92.1%), and above high school education (100%). Mean VA and IOP were 82.7 ETDRS letters (Snellen equivalent 20/25) and 14.5mmHg; mean CS was -2.1 for 3CPD and -1.8 for 6 CPD. Despite the majority of participants having normal CASI scores, VA and presence of any eye disease were significantly associated with CASI score after adjusting for age, sex, race, years of education, smoking, and APOE status (0.14 [0.03, 0.26], 1.36 [0.33, 2.39], respectively). None of the retinal imaging measures had statistically significant associations with CASI scores.

Conclusions : Significant associations were found between VA and cognitive function among Eye ACT participants who were primarily cognitively normal. Further longitudinal follow ups are needed to validate the reliability of these findings and how visual function measures may complement retinal imaging findings.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.