Eye Adult Changes in Thought (Eye ACT) study: Settings and report on the inaugural cohort

Abstract

Purpose : To describe the settings and compare demographic and baseline clinical factors of the inaugural Eye Adult Changes in Thought (ACT) study participants.

Methods : Adult Changes in Thought (ACT) is an ongoing cohort study of older adults (≥65 years) randomly recruited from Kaiser Permanente Washington who were cognitively normal at enrollment and followed biennially for onset of Alzheimer’s disease since 1994. Cognitive testing included the Cognitive Abilities Screening Instrument (CASI) with other measures of cognition. Since 12/2021, the Eye ACT study has recruited from the parent ACT study and assessed visual function, eye pressure, and multimodal retinal imaging. Eye ACT is unique in that participants may either be evaluated at the research clinic or in their homes. Comparisons of demographic and baseline clinical information between parent ACT participants, first 300 Eye ACT clinic participants, and first 30 Eye ACT home participants were performed.

Results : Compared to ACT participants, Eye ACT participants were younger, newer to ACT, more educated, and healthier (lower rates of cardiovascular disease, cerebrovascular disease, and hypertension, p-values all <0.05) (Table 1). Eye ACT participants had lower rates of visual impairment (12 vs. 22%, p<0.001) and age-related macular degeneration (18 vs. 25%, p=0.02). People seen at home were older (mean age 77.2 vs. 74.9, p=0.015), more likely to be female (60% vs. 49%, p=0.026), and had significantly worse visual acuity (71.1 vs 78.9 ETDRS letters, p<0.0001) and contrast sensitivity (-1.85 vs -2.06 mean log units at 3 cycles per degree [CPD], p=0.002) compared to those seen in clinic. CASI scores and optical coherence measurements were similar between two groups (Table 2).

Conclusions : Home visit participants had significantly lower visual function measures compared to research clinic participants. Home visits enable data collection from participants who are often underrepresented in dementia research and may have different dementia risk profiles. Functional measurements of retinal health and study settings are important considerations when evaluating potential retinal biomarkers of dementia.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Table 1. Demographic and clinical information of Adult Changes in Thought (ACT) total enrollment cohort, ACT cohort at risk of Alzheimer’s disease, and Eye ACT cohort to date.

 

Table 2. Baseline Eye ACT data from clinic and home visit participants.