|Recent studies provide stronger evidence on OCT’s diagnostic utility in detecting cognitive decline. Click image to enlarge.|
Upon evaluating the existing literature reporting an association between retinal markers and cognitive impairment in adults older than 65, researchers recently found that retinal nerve fiber layer thickness is linked with cognitive performance and, therefore, may have the potential to detect cognitive impairment in older adults.
This systematic review of peer-reviewed empirical articles investigating the association between retinal markers and cognitive impairment in the elderly evaluated three electronic databases, Medline, PsycINFO and EMBASE. Sixty-seven eligible studies examining 6,815 older adults were included, the majority of which were cross-sectional (90%).
OCT was the most commonly used retinal scanning method to measure the thickness of the retinal nerve fiber layer, ganglion cell complex, choroid and macula. Just over half of the cross-sectional studies using OCT reported an association between thinning of at least one retinal parameter and poor cognition. The longitudinal studies (9%) using OCT also identified a connection between reduced retinal nerve fiber layer thickness and cognitive decline.
“While cross-sectional studies show moderate support between retinal scanning methods and cognitive impairment, recent longitudinal studies provide stronger evidence on the diagnostic utility of OCT in detecting a declining cognitive status,” the study authors concluded in their paper. “Further longitudinal studies should be conducted to corroborate these findings before retinal scanning can be introduced into clinical practice as a viable tool for detecting cognitive impairment. Studies using more sensitive cognitive screening tools are required to assess the viability of retinal measures as a biomarker in cognitive decline.”
Jeevakumar V, Sefton R, Chan J, et al. Association between retinal markers and cognition in older adults: a systematic review. BMJ Open Ophthalmol. June 21, 2022. [Epub ahead of print].