New study highlights that type 2 diabetes (T2D) is associated with a decline in brain function over 5 years in older people.

‘Type 2 diabetes (T2D) is associated with a decline in verbal memory and fluency over five years, reveals a new study.’
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However, contrary to previous studies, the decrease in brain volume often found in older people with T2D was not found to be directly associated with cognitive decline during this time period. Yet compared with people without T2D, those with T2D had evidence of greater brain atrophy at the beginning of the study.Read More..





Previous research has shown that T2D can double the risk of dementia in older people. In this new study, Dr. Michele Callisaya (University of Tasmania, Hobart, TAS, and Monash University, Melbourne, VIC, Australia) and colleagues aimed to discover whether type 2 diabetes is associated with greater brain atrophy and cognitive decline, and whether the two are linked. It is the first study to compare decline in both cognition and brain atrophy between people with and without T2D together in the same study.
The trial recruited 705 people aged 55-90 years from the Cognition and Diabetes in Older Tasmanians (CDOT) study. There were 348 people with T2D (mean age 68 years) and 357 without (mean age 72 years) who underwent brain MRI (lateral ventricular and total brain volume - measures of brain atrophy) and neuropsychological measures (global function and seven cognitive domains) at three time points over a mean follow-up period of 4.6 years.
The results were adjusted for age, sex, education and vascular risk factors including past or current smoking, heart attack, stroke, high blood pressure, high cholesterol, and body mass index. The authors reported there were significant associations found between T2D and greater decline in both verbal memory and verbal fluency.
Although people with diabetes had evidence of greater brain atrophy at the start of the study, there was no difference in the rate of brain atrophy between those with and without diabetes over the time course in this study. There was also no evidence in the study that the rate of brain atrophy directly impacted on the diabetes-cognition relationship.
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They add: "Contrary to our hypotheses and results from previous cross-sectional studies, the rate of brain atrophy over these 5 years of study did not directly mediate associations between type 2 diabetes and cognitive decline. It is possible that greater accrual of cerebrovascular disease than occurred in our study may be more likely to reveal whether there is such a relationship."
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Source-Eurekalert