Race moderates age-related cognitive decline in type 2 diabetes.

The age-related rate of cognitive decline in patients with diabetes mellitus has received relatively little attention. In this cross-sectional study, Caucasian (N = 145) and African American (N = 25) males with diabetes mellitus were recruited to examine age-related changes in cognitive performance. It is known that African Americans with diabetes mellitus are at increased risk for more frequent and more severe diabetes-related complications. It was hypothesized that such complications may accelerate age-related cognitive decline in African Americans. Three timed tests varying in complexity assessed attention, mental flexibility, and learning. Advancing age was uniformly associated with decreasing cognitive performance but only on more complex tasks did race moderate this relationship. A steeper age-related decline was observed in African Americans on more complex cognitive tests. Diabetes may be an accelerated form of aging that impacts cognition and race appears to differentially moderate this relationship.