Diabetes and Buildup of Tau May Be Linked

People with type 2 diabetes may have a greater buildup of tangles of protein in their spinal fluid, irrespective of dementia, according to a new study published Sept. 2 in Neurology.

The study, led by researchers at Monash University in Melbourne, Australia, looked at the relationship between type 2 diabetes, the levels of beta amyloid and tau protein in the spinal fluid, and the loss of brain cells and their connection.

Of the 816 participants involved, 124 had diabetes, 397 had mild cognitive impairment, 191 had Alzheimer’s disease and 228 had no memory and thinking problems. The average age of participants was 74.

Participants with diabetes, on average, had 16 picograms per milliliter greater levels of the tau protein in the spinal and brain fluid, regardless of whether or not they had dementia, which may reflect a greater buildup of tangles in the brain.

“Evidence shows that people with type 2 diabetes have double the risk of developing dementia,” said author Velandai Srikanth, M.D., Ph.D. “This interesting development further defines how the diseases may be connected.”

The accumulation of tangles may also contribute to the loss of brain tissue, and according to the study, diabetes was associated with an average of 0.03 millimeter less cortical tissue in brains of participants who had diabetes than those who did not.

“Due to the fact that nerve cells in the brain do not replace themselves, it is extremely important to find ways to reduce the death of current brain cells. Studies such as ours seek to understand how diseases like diabetes may directly or indirectly affect brain cell death,” Srikanth said.

The study did not determine a cause-and-effect relationship between diabetes and brain tangles.