Healthy adults did significantly better than diabetics on two tests of mental functioning - executive functioning and speed of response, the team at the University of Alberta found.
"Speed and executive functioning are thought to be among the major components of cognitive health," Roger Dixon, who worked on the study, said in a statement.Executive functioning includes the ability to focus, work with new information to solve problems and to give thoughtful answers to questions.
Writing in the journal Neuropsychology, the researchers said they studied 41 adults aged 53 to 90 with type 2 diabetes and 424 adults in good health.
Changes occur early
There were few differences between adults under and over the age of 70, which suggests the changes occur early, Dixon said.
"There could be some ways to compensate for these declines, at least early and with proper management," he said.
Diabetes is known to raise the risk of diseases such as Alzheimer's. The high blood sugar levels caused by the condition can damage both blood vessels and nerves and lead to damage in many organs.
A study published in July showed that diabetics who take insulin plus a diabetes pill have a lower risk of developing Alzheimer's disease than diabetics who take insulin alone.
(Reuters Health, January 2009)
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