Retinal microvascular signs and functional loss in older persons: the cardiovascular health study.

BACKGROUND AND
PURPOSE: We hypothesized that retinal microvascular signs are associated with executive dysfunction, slow gait, and depressive mood, which are characteristic features of microvascular disease affecting frontal subcortical regions of the brain.
METHODS: In the Cardiovascular Health Study, 1744 participants (mean age, 78) free of stroke had retinal photographs and carotid ultrasound during the 1997 to 1998 visit. We examined the cross-sectional association of retinal signs with the digit-symbol substitution test (DSST) score, gait speed, the Center for Epidemiologic Studies-Depression score, and depressive mood, defined as Center for Epidemiologic Studies-Depression score >9 or antidepressant use.
RESULTS: After adjusting for potential confounders, retinal signs were associated with lower DSST score (generalized arteriolar narrowing and arteriovenous nicking), slower gait (retinopathy), and depressive mood (generalized arteriolar narrowing). A higher number of retinal signs was associated with lower DSST score (-0.76 and -2.79 points for 1 sign and ≥2 signs versus none; P<0.001) and slower gait (-0.009 and -0.083 m/s; P=0.047), but not with the square root of Center for Epidemiologic Studies-Depression score (0.079 and -0.208; P=0.072). In addition, coexistence of retinal signs (generalized arteriolar narrowing and arteriovenous nicking) and carotid atherosclerosis was associated with lower DSST score compared with either process alone (P for interaction <0.01). Notably, further adjustment for ventricular size, white matter disease, and infarcts on MRI did not attenuate the association.
CONCLUSIONS: Retinal signs are associated with executive dysfunction and slow gait, and possibly with depressive mood, suggesting a common process involving small vessels.