Abstract
Purpose :
To describe the cross-sectional relationships of the microvasculature as measured by retinal arteriolar and venular diameters (CRAE and CRVE, respectively) to cognitive function in persons with type 1 diabetes in the WESDR.
Methods :
There were 244 persons with type 1 diabetes who participated and underwent cognitive assessment at a 32-year follow-up examination of the WESDR in 2012-2014. Computer-assisted software (IVAN) was used to measure the CRAE and CRVE from digitally scanned fundus photographs. Twelve validated psychometric tasks were administered and z-scores were calculated for the population. Factor analysis identified three broad cognitive domains: psychomotor efficiency and executive function, nonverbal memory, and verbal memory. Analyses were performed separately for each domain. Stepwise regression identified the most parsimonious models.
Results :
The mean age and duration of type 1 diabetes in the cohort were 55 years (range 37-82 years) and 41 years (range 33-55 years), respectively. The mean and standard deviation of CRAE and CRVE were 146 ± 19.9 μm and 217 ± 29.3 μm, respectively. Both CRAE (beta estimate 0.147 per 10 μm, P<0.001) and CRVE (beta estimate -0.119 per 15 μm, P<0.01) were associated with mental efficiency in the most parsimonious model, which included age, diabetes duration, education, history of cardiovascular disease, presence of carotid artery plaques, and severe hypoglycemia. Additional adjustment for A1c level, a history of diabetic neuropathy, presence of proliferative diabetic retinopathy, and retinal photocoagulation status did not attenuate these relationships. Retinal vessel diameters were not related to other domains.
Conclusions :
These data show that independent of other diabetes-related factors, retinal venular and retinal arteriolar diameters are cross-sectionally associated with cognitive function as measured by mental efficiency in persons with type 1 diabetes of long duration. Given the well-established relationship between the retinal and the cerebral microvasculatures, our findings provide additional support for the hypothesis that alterations in cerebral microvasculature may contribute to the development of cognitive slowing typically seen in patients with type 1 diabetes.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.