Prevalence of Retinal Signs and Association With Cognitive Status: The ARIC Neurocognitive Study.

OBJECTIVE: To determine the prevalence of retinal microvascular signs and associations between retinal signs and cognitive status.

DESIGN: Cross-sectional analysis of visit 5 (2011-2013) of the Atherosclerosis Risk in Communities (ARIC) cohort. Data analysis took place November 30, 2017, to May 1, 2018.

SETTING: Biracial population-based cohort from four US communities.

PARTICIPANTS: A total of 2624 participants with a mean age of 76 years (SD = 5 years) (19% African American) with data on cognitive status and complete retinal examination.

MEASUREMENTS: Retinal signs measured with fundus photography. Cognitive status: normal cognition, mild cognitive impairment (MCI)/dementia with a primary diagnosis of Alzheimer disease (AD) without cerebrovascular disease (CVD), and MCI/dementia with a primary or secondary diagnosis of CVD (irrespective of AD).

RESULTS: Overall, 6% of the cohort had mild retinopathy and 2% had moderate/severe retinopathy. Of the cohort, 7% had microaneurysms, 6% had retinal hemorrhages, and 8% had arteriovenous (AV) nicking. There was a low prevalence of soft exudates (1%) and focal narrowing (1%). In weighted fully adjusted models, individuals with retinal hemorrhages had a two-fold higher odds of all-cause MCI/dementia (95% confidence interval [CI] = 1.3-3.0; P = .001) and a 2.5-fold higher odds (95% CI = 1.6-3.9; P < .001) of MCI/dementia with CVD compared to individuals with no retinal hemorrhages. Individuals with AV nicking had a 1.6-fold higher odds of MCI/dementia with CVD (95% CI = 1.0-2.4) compared to individuals with no AV nicking (P < .05). There were no associations between retinal signs and MCI/dementia without CVD.

CONCLUSION: Our findings are confirmatory of recent research, and suggest that retinal microvascular signs may reflect microvascular pathology in the brain, potentially contributing to dementia and earlier MCI. The low prevalence of retinal signs and modest associations with cognitive status, however, limit the current clinical utility of these findings. Further work is needed to determine whether more sophisticated imaging may detect more subtle retinal signs with higher sensitivity to identify individuals at risk of dementia.