Retinopathy and cognitive impairment in adults with CKD.

BACKGROUND

Retinal microvascular abnormalities have been associated with cognitive impairment, possibly serving as a marker of cerebral small-vessel disease. This relationship has not been evaluated in persons with chronic kidney disease (CKD), a condition associated with increased risk of both retinal pathology and cognitive impairment.

STUDY

DESIGN

Cross-sectional study.

SETTING &

PARTICIPANTS

588 participants 52 years or older with CKD in the Chronic Renal Insufficiency Cohort (CRIC) Study.

PREDICTOR: Retinopathy graded using the Early Treatment Diabetic Retinopathy Study severity scale and diameters of retinal vessels.

OUTCOMES: Neuropsychological battery of 6 cognitive tests.

MEASUREMENTS: Logistic regression models were used to evaluate the association of retinopathy, individual retinopathy features, and retinal vessel diameters with cognitive impairment (≤1 SD from the mean), and linear regression models were used to compare cognitive test scores across levels of retinopathy, adjusting for age, race, sex, education, and medical comorbid conditions.

RESULTS

The mean age of the cohort was 65.3±5.6 (SD) years, 51.9% were nonwhite, and 52.6% were men. The prevalence of retinopathy was 30.1%, and the prevalence of cognitive impairment was 14.3%. Compared with those without retinopathy, participants with retinopathy had an increased likelihood of cognitive impairment on executive function (35.1% vs 11.5%; OR, 3.4 [95% CI, 2.0-6.0]), attention (26.7% vs 7.3%; OR, 3.0 [95% CI, 1.8-4.9]), and naming (26.0% vs 10.0%; OR, 2.1 [95% CI, 1.2-3.4]) after multivariable adjustment. Increased level of retinopathy also was associated with lower cognitive performance on executive function and attention. Microaneurysms were associated with cognitive impairment on some domains, but there were no significant associations with other retinal measures after multivariable adjustment.

LIMITATIONS: Unknown temporal relationship between retinopathy and impairment.

CONCLUSIONS

In adults with CKD, retinopathy is associated with poor performance on several cognitive domains, including executive function and attention. Evaluation of retinal microvascular abnormalities may be a promising tool for identifying patients with CKD who are at increased risk of cognitive impairment.