Patients can protect against stress by controlling their blood sugar levels
Stress increases the risk of memory loss and cognitive decline in older people with diabetes, according to a new study.
Researchers from Edinburgh University looked at 900 men and women aged between 60 and 75 with type 2 diabetes.
They found brain function slowed in those who had higher levels of the stress hormone cortisol in their blood.
Memory loss is a recognised symptom among older diabetics but until now there was little evidence as to why.
Dr Rebecca Reynolds, of the university's Centre for Cardiovascular Science, said: "We know that type 2 diabetes is linked to problems with memory, but the reason behind this is unclear.
"This study shows that older people with diabetes who have higher levels of stress hormones in their blood are more likely to have experienced cognitive decline.
"It may be that by regulating cortisol levels, we could help improve cognitive decline in patients with type 2 diabetes."
The research published by Diabetes Care is part of the Edinburgh Type 2 Diabetes Study.
Scientists evaluated mental abilities with a range of tests, which included looking at memory and assessing how quickly participants processed information.
They compared this with general intelligence levels, using vocabulary tests, to work out whether brain function in participants had diminished over time.
Factors such as education, cardiovascular disease, smoking and mood were also taken into account.
Blood samples were taken from participants in the morning to assess levels of cortisol.
The best way for diabetics to protect themselves against increased stress levels is to keep control of their blood sugar.
Researchers now want to repeat the study to see if there is any further evidence of memory loss in those who took part in the original tests.