A study by researchers in the US has shown that a decline in the memory and thinking ability of people with type 2 diabetes is associated with changes in blood flow in the brain.
Different parts of the brain can be more or less active depending on what a person is doing. It is important for the blood supply to respond to the needs of the brain and provide more active areas with more blood. The regulation of the blood supply can be affected in diabetes and this study aimed to find out if this could be related to the increased rate of decline in memory and thinking associated with the disease.
The researchers worked with 40 people, 19 who had type 2 diabetes and 21 who did not have diabetes. None of the volunteers had dementia. The participants took part in a number of tests including tests of memory and thinking, MRI scans which looked at blood flow in the brain, and blood tests which looked at signs of inflammation. The tests were repeated after an interval of two years.
Only the group with diabetes showed a decline in scores of memory and thinking over the two years of the study. MRI scans revealed that this decline was associated with changes in the way blood flow in the brain is regulated, which is in turn associated with levels of inflammatory proteins in the blood. The results suggest these processes are linked together and could have an effect on the daily lives of people living with diabetes.
Dr Laura Phipps of Alzheimer’s Research UK said:
“Though there is a well-established link between diabetes and an increased risk of dementia, this research did not look at that relationship directly but focused on memory decline in those without dementia. This small study highlights a possible mechanism that could play a role in affecting memory and thinking skills in people with diabetes, but this association is complex and still not fully understood. We know that inflammation is being implicated in diseases like Alzheimer’s, and while it’s interesting to see it may also impact on the brain’s ability to divert blood flow, it’s hard to separate cause and effect in this kind of research. Studies involving more people, tested over longer periods of time, will be needed before a clearer picture can emerge.
“Current evidence suggests that a balanced diet, drinking in moderation, not smoking, keeping blood pressure and cholesterol in check, and staying mentally and physically active could all help to maintain a healthy brain as we get older.”