Cognitive Function in Type 2 Diabetes: A Study Using Younger Adults

Background: The rising rates of Type 2 diabetes (T2DM) around the world have serious economic and health implications, often related to the complications of the condition. One such problem is the impact of diabetes on cognitive function. In older adults with T2DM, there is an established relationship between diabetes and cognitive impairment in people with and without dementia. Emerging evidence suggests this may also be the case for younger adults, as the occurrence of cognitive deficits in people with T2DM is related to the severity and duration of the condition. In some parts of the world, T2DM has become the most common diabetes phenotype in children. Therefore, exploring the cognitive function of younger adults with T2DM is important, to understand the pathogenesis and sequelae of the condition across the lifespan.

Aims: To investigate if younger adults with T2DM show signs of cognitive impairment, and how this relates to diabetes-related health indicators.

Method: Ten people with T2DM were recruited from a diabetes clinic in London, and completed a battery of cognitive tests assessing processing speed, attention, executive function, learning and memory. Estimates of optimal (premorbid) ability were also derived. Clinically relevant markers for diabetes were recorded, including Hba1c and lipid profiles.

Results: Scores on cognitive tests suggested deficits in attention and processing speed, but executive function was a relative strength. Scores were not declined relative to one measure of optimal ability across the group. Health markers related to diabetes were correlated with several cognitive domains, although not consistently: total cholesterol levels showed the strongest associations, and not always in the direction anticipated.

Conclusions: Due to the small sample size, any profiles and associations should be treated cautiously. Further research in this area is needed, and cognitive impairment in people with T2DM should be attended to routinely in clinical services.