Cognitive decline in type 2 diabetesAgainst this background, Richard Tuligenga and colleagues analysis4 from the Whitehall II cohort study in The Lancet Diabetes & Endocrinology addresses the questions of whether type 2 diabetes is associated with cognitive decline before old age, and whether glycaemic control and disease duration are risk factors for faster cognitive decline.

They report that diabetes was associated with accelerated cognitive decline and that both disease duration and glycaemic control (assessed by HbA1c) were important risk factors.

In people with type 2 diabetes, cognitive decrements are most consistently reported for measures of verbal memory and informationprocessing speed, although in older individuals with diabetes decrements in executive functioning (ie, higher-order functions that allow for planning, goal-directed behaviour, and attention) can also be seenCognitive decline in individuals with type 2 diabetes aff ects memory, information processing, and executive functioning. It can start in middle age, is aff ected by diabetes duration and glycaemic control, and can accelerate with age.

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