Abstract
Purpose :
Cognitive impairment caused by Alzheimer’s and other dementias quality of life and social engagement. Vascular disease may contribute substantially to the total burden of dementia and its precursor, MCI. Cerebral micro vascular changes - important contributors to cognitive impairments - are difficult to detect with brain imaging. Here we examined the correlation of retinal vessel density (VD) with concurrent cognitive function in an aging population-based bi-racial sample.
Methods :
The EyeDOC study used optical coherence tomographic angiography (OCTA) to capture macular retinal vascular changes in a 6 X 6 mm area. In a cross-sectional analysis of the clinical study data, the associations between VD and cognitive performance were assessed by multivariate regression analysis of cognitive function z-scores (for global function as well as language, memory and executive function domains) or mild cognitive impairment (MCI) status on VD, controlling for age, race and education. VD in the superficial vascular complex [SVC], intermediate capillary plexus [ICP] and deep capillary plexus [DCP] were examined. Included participants were those with OCTA and cognition measurements without evidence of eye disease.
Results :
Among 206 eyes from 177 participants (50% black; 67% female; mean age 78 years [range: 71-93 years]), the mean (SD) SVC, ICP and DCP VD was 48.0% (7.2), 35.2% (5.9) and 20.0% (6.8), respectively (Figure). Among the 191 eyes without eye disease, there were no significant associations of VD in the SVC, ICP or DCP with global or domain specific cognitive function (Table). Lowess fits to data did not indicate meaningful nonlinear trends. Among the covariates, college level education was the strongest predictor of cognitive function, with 0.8 SDs higher global cognitive performance among college educated compared to high school or less education (p<0.001). Associations of VD with MCI were similarly small and non-significant.
Conclusions :
The EyeDOC study seeks to use the eye as a window into cognitive impairments. These preliminary results suggest that VD in the vascular layers of the retina is not correlated with cognitive function or risk of MCI.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.