Abstract
Background
Accumulating evidence indicates that microvascular alterations in the brain, especially at the capillary level, are one of the major contributors to cognitive impairment and dementia in older adults. The brain and retinal microvasculature share similar anatomic and physiologic features. Alterations of retinal microvasculature reflect similar changes in brain. We examined the associations between retinal microvascular density, cognition and physical fitness in healthy older adults with no reported cognitive decline.
Method
Twenty cognitively normal older adults (age: 70.3 ± 4.6 years) were recruited. Both eyes of each subject were imaged using optical coherence tomography angiography. The vessel density of the retinal vascular network (RVN), superficial vascular plexus (SVP), and deep vascular plexus (DVP) was measured. Cognitive function was tested using the Mini‐mental state examination (MMSE) and Montreal Cognitive Assessment (MoCA), while physical performance was evaluated using the YMCA cycle ergometer test. Partial correlations (rpartial ) were computed between measures of retinal microvascular density, cognitive function, and physical performance.
Result
The MoCA was significantly correlated to vessel density of RVN (rpartial = 0.54, P = 0.002) and SVP (rpartial = 0.59, P < 0.001), but not DVP (rpartial = ‐0.01, P = 0.99). MoCA also showed a trend toward correlation with YMCA total work (TW‐YMCA, rpartial = 0.28, P = 0.14). Retinal microvascular density was not related to TW‐YMCA (rpartial= ‐ 0.23 ∼ 0.12, P > 0.05).
Conclusion
The MoCA was significantly correlated to vessel density of RVN (rpartial = 0.54, P = 0.002) and SVP (rpartial = 0.59, P < 0.001), but not DVP (rpartial = ‐0.01, P = 0.99). MoCA also showed a trend toward correlation with YMCA total work (TW‐YMCA, rpartial = 0.28, P = 0.14). Retinal microvascular density was not related to TW‐YMCA (rpartial= ‐ 0.23 ∼ 0.12, P > 0.05).