Blood glucose spikes impair mental function

People with type 2 diabetes experience a decline in mental function and mood during episodes of hyperglycemia - an excessive rise in blood glucose - according to new study findings.

Dr. Brian M. Frier, of Royal Infirmary of Edinburgh, UK, and colleagues examined the effects of acute hyperglycemia in 20 patients with type 2 diabetes.

As reported in the medical journal Diabetes Care, the participants were 61 years old on average and had diabetes for about 6 years. They were on various types of treatment, including antidiabetic medication and insulin.

The team used a glucose infusion to produce optimal blood glucose levels or high levels on two occasions. During this process, the researchers tested the subjects' information processing ability, memory, and attention level.

In addition, the patients completed a mood questionnaire during each experimental condition.

During acute hyperglycemia, speed of information processing, working memory, and some areas of attention were impaired.

Acute hyperglycemia also adversely affected mood, with reduced feelings of happiness and increased agitation, anxiety, lethargy, and tiredness.

"The deleterious effects of hyperglycemia on cognitive function and mood states may significantly interfere with many activities of daily living," Frier's group concludes. These effects may in turn affect patients' ability to comply with strategies aimed at treating spikes in blood glucose that occur after meals.

SOURCE: Diabetes Care, October 2004.