A recent Australian study finds that older patients with diabetes may struggle more with verbal memory and fluency than those without diabetes.
The aim of the study was to examine whether type 2 diabetes is associated with greater brain atrophy and cognitive decline and whether brain atrophy intervenes between type 2 diabetes and cognitive decline in any way.
How Was The Study Conducted?
Participants who did not have dementia ranging from 55–90 years old were recruited from the Cognition and Diabetes in Older Tasmanians study.
They underwent brain MRI and neuropsychological measures, which tested for global function and seven cognitive domains.
The assessments were done during three different time intervals over five years.
The researchers used mixed models to examine associations of type 2 diabetes with cognitive and MRI measures. A test of mediation was used to determine whether brain atrophy explained associations between type 2 diabetes and cognitive decline.
What Did Researchers Find?
Out of a total of 705 participants, 348 had diabetes, with a mean age of 68, and 357 participants did not diabetes, with a mean age of 72.5 years.
Adjusting for age, sex, education and vascular risk factors, the researchers found that in people with diabetes, verbal fluency declined slightly over the course of the study, while it improved slightly in participants without diabetes
The researchers indicate people with diabetes already had more brain atrophy at the start of the study, however, there was no difference between those with and without diabetes in the rate of brain atrophy during the study.
They also state that atrophy doesn’t clearly explain the link between diabetes and cognitive decline.
The researchers conclude that in the older community, type 2 diabetes is associated with a decline in verbal memory and fluency over approximately 5 years.
This, they say, suggests the effect of diabetes on brain atrophy may begin earlier in life.