Ankle-brachial index and inter-artery blood pressure differences as predictors of cognitive function in overweight and obese older adults with diabetes: results from the Action for Health in Diabetes movement and memory study.

Objective: Ankle-brachial index (ABI) and interartery systolic blood pressure differences, as markers of vascular disease, are plausible risk factors for deficits in cognitive function among overweight and obese adults with type 2 diabetes.

Methods: The ABI and maximum interartery differences (MIAD) in systolic blood pressures were assessed annually for five years among 479 participants assigned to the control condition in a randomized clinical trial of a behavioral weight loss intervention. A battery of standardized cognitive function tests was administered 4 to 5 years later. Analyses of covariance were used to assess relationships that ABI, MIAD, and progression of ABI and MIAD had with cognitive function.

Results: There was a curvilinear relationship between ABI and a composite index of cognitive function (p = 0.03), with lower ABI being associated with poorer function. In graded fashions, both greater MIAD and increases in MIAD over time also had modest relationships with poorer verbal memory (both p ≤ 0.05), processing speed (both p ≤ 0.05), and composite cognitive function (both p < 0.04). These relationships were independent of each other and remained evident after extensive covariate adjustment.

Conclusions: In overweight and obese adults with type 2 diabetes, lower ABI and larger interartery systolic blood pressure differences have modest, independent, graded relationships with poorer cognitive function 4-5 years later.