Type 2 diabetes may affect brain function earlier than researchers first thought, evidence has suggested.
An Australian study set out to look at how dementia affects brain health. Whilst diabetes has been associated with greater risks of dementia, there is evidence to suggest that the risk could be reduced through following a healthy lifestyle and achieving healthy blood glucose levels.
The trial involved 705 people for four-and-a-half years who did not have dementia. Of that number, 348 had type 2 diabetes.
Those who had diabetes and participated were a bit younger, aged roughly about 68, compared with the average of 72 of the volunteers who did not have the condition.
Throughout the trial all participants underwent brain scans to look for tissue shrinkage – known as brain atrophy. They also took part in cognitive tests assessing verbal skills.
Those with diabetes already displayed evidence of smaller brain volume at the beginning, suggesting that changes to the brain start much earlier than first thought in those with diabetes, perhaps even in middle age. However, no additional brain shrinkage was seen over the course of the study.
Lead author Michele Callisaya, from the University of Tasmania in Hobart, Australia, said: “Recommendations for good brain health include physical activity, following a healthy diet, maintaining a healthy weight, checking blood pressure and cholesterol, mentally challenging the brain and enjoying social activities.”
The team also found evidence to suggest that diabetes impacts older people’s speech skills, known as verbal fluency. Those without the condition did not experience a decline at all.
The researchers did note that all the participants with type 2 diabetes had well-controlled blood sugar levels. This could mean that those who have greater difficulty controlling their diabetes, might experience greater brain changes over time.
The findings have been published in the Diabetologia journal.
The researchers concluded: “In older community-dwelling people, type 2 diabetes is associated with decline in verbal memory and fluency over 5 years. The effect of diabetes on brain atrophy may begin earlier (midlife).”
