Cognition, Cerebral Vasoreactivity Declined in Type 2 Diabetes

(HealthDay News) — In as little as 2 years, patients with type 2 diabetes may exhibit diminished global and regional cerebral vasoreactivity, which could negatively affect cognitive skills, a small study suggests. 

The findings were published in Neurology.

In the study, the researchers evaluated 40 people with an average age of 66 years. Nineteen of the study volunteers had type 2 diabetes, and 21 were healthy control subjects. 

The researchers tested everyone at the start of the study, and again 2 years later. The volunteers completed cognitive and memory tests. They also underwent magnetic resonance imaging (MRI) to measure global and regional cerebral perfusion and vasoreactivity, and had blood tests to measure their average blood glucose levels and inflammatory markers.

At the 2-year mark, those with type 2 diabetes had diminished global and regional cerebral vasoreactivity and a decline in multiple cognitive tasks. 

On one test that looked at learning and memory, the scores of those with diabetes decreased an average of 12%, from 46 to 41 points. Those without type 2 diabetes stayed at an average of 55 points over the 2 years. 

Further, the higher the inflammation levels, the greater the decrease in cerebral vasoreactivity and vasodilation, the research team found. That was true even for people who had good control of their diabetes. 

Cerebral vasoreactivity was decreased 65% in the people with type 2 diabetes, according to the data.

“Our major finding is we have linked the acceleration of the cognitive decline to impaired blood flow regulation in the brain,” senior author Vera Novak, MD, PhD, an associate professor of neurology at Harvard Medical School in Boston, told HealthDay.


  1. Chung C-C et al. Neurology. 2015;doi:10.1212/WNL.0000000000001820.