Pilot study examining the relationship between retinal vasculature and cognition in older adults recently discharged from a 12-week cardiac rehabilitation program

Abstract

Background: Cardiovascular disease increases the risk for cerebrovascular disease (CBVD) and cognitive decline. The retina has become an ideal target for imaging cerebrovascular changes via optical coherence tomography angiography (OCTA). Whether OCTA metrics map onto clinical outcomes in adults at high risk for CBVD and cognitive decline remains unknown.

Objectives: This study examined the relationship between OCTA metrics and domain-specific cognition in older adults recently discharged from a 12-week cardiac rehabilitation program, who are at high risk of both CBVD and cognitive decline.

Design: This was a prospective, feasibility/pilot study to determine whether OCTA metrics are related to cognition in this unique population of high-risk adults.

Methods: Twenty-two older adults recruited within 3 months of completing a 12-week cardiac rehabilitation program participated in a single visit consisting of cognitive assessment and OCTA imaging. Cardiac/exercise metrics were compared pre- and post-rehabilitation. Primary outcomes were analyzed using partial correlation, and multiple regression assessed whether exercise moderates the relationship between retinal vasculature and cognition.

Results: Higher performance in episodic memory predicted retinal vascular perfusion. Change in time spent performing exercise and change in systolic blood pressure from pre- to post-cardiac rehabilitation were associated with higher logical memory performance post-rehab. Exercise did not moderate the relationship between retinal vascular perfusion and cognition.

Conclusion: The results of this study support a direct relationship between retinal vascular integrity and cognition in those at high risk for cognitive impairment and cardiovascular disease (CVD). Future research in larger samples with data collection both pre- and post-cardiac rehabilitation will inform whether this relationship is mediated by exercise.

Keywords: OCTA; biomarkers; cardiac rehabilitation; cerebrovascular disease; cognition; retina.

Figure 1.

Scatterplots showing significant associations between ISL Item Recall and FAZ Area (a), weight change and FAZ area (b), exercise difference and logical memory percent retention (c), and weight change and FAS verbal fluency sum (d). Dark lines represent lines of best fit. FAS, F-A-S Verbal Fluency Test; FAZ, foveal avascular zone; mm sq, millimeters squared.