Soon after diabetes sets in, researchers at the University of Alberta say gradual slowing down of mental abilities follows.
Their conclusion is based on a study, in which they found that semantic speed and higher functions such as planning, organising and paying attention to details were noticeably worse in patients with type 2 diabetes than in healthy adults.
The researchers also found that the mental deterioration was no better in younger adults with diabetes than in an older group, suggesting that the damage is done early in the disease and remains stable thereafter.
"Speed and executive functioning are thought to be among the major components of cognitive health," Times Online quoted Roger Dixon, the study's co-author, as saying.
"The good news is that, at this point, the cognitive slowing would not be notable in most older diabetes patients' everyday life activities. It may be noticed, however, if the patient is involved in technical psychomotor tasks (such as video games) requiring quick and accurate responses or monitoring. The bad news is that this slowing may indicate the 'leading edge' of progressive cognitive decline occurring with diabetes, and it will likely get worse without careful disease management," he added.
The study used 41 adults with diabetes and 424 without, aged 53 to 90.
Previous studies have suggested that diabetes may impede cognition, but the new study is the first to identify, which elements of brain function are
affected and to show that the effects appear early in the progress of the disease.
The study is published in the journal Neuropsychology.