The Mental Challenge

Diabetes and cognitive ability

Cognition can be defined as the psychological effect of perception, learning and reasoning. Many diabetics are seen to have a lowered ability of cognition. In particular diabetes has been linked to cognitive impairment in the elderly, although there is a dearth of studies that have made the relationship clear enough. As one might expect, those with impaired cognitive function are less likely to manage their own diabetes and need to depend more on the use of health and social services.

Recent studies have indicated that people with uncontrolled diabetes had almost twice the risk of cognitive dysfunction as those who did not have diabetes. However researchers say that well controlled diabetes may not increase the risk of reduced cognitive abilities. Therefore it is important to keep glucose levels under control so that diabetics may be able to keep their mental functioning intact apart from performing activities of daily living.

Possible Causes

Poorly controlled diabetes may hamper cognition by damaging the microvessels of the brain and causing small strokes. Although these strokes could be small they could be large enough to produce damage that affects cognitive function. Some experts in the field also hypothesize that a high level of glucose may directly damage the neurons.

Some studies indicate that brain abnormalities are common in patients with type 1 diabetes of long duration and are suggestive of premature aging of the brain.

Although the mechanism behind cognitive impairment is not clear enough, some studies have shown that years of education and socioeconomic status, as well as age, are strongly associated with cognitive dysfunction.

However, the tricky part is whether diabetes contributes to the initial decline in cognitive function or whether it is just an age-related phenomenon, which occurs in parallel with the development of diabetes.

Certainly, more work is needed to identify the mechanisms linking diabetes with poor cognitive function. However, the clinical application of these findings is clear: cognitive function screening tools would be useful in identifying those patients with impaired cognition so that additional help can be provided to them, or advice to their family, in managing their diabetes.

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