Diabetic retinopathy could be associated with poorer memory and diminished brain power in people with Type 2 diabetes, according to new research announced this week at Diabetes UK's Annual Professional Conference.
The study looked at 1,066 people with Type 2 diabetes aged between 60 and 75 years. Participants completed seven tests looking at memory, logic and concentration to establish their level of brain function. Those with retinopathy had worse average scores on most of the individual tests as well as on general cognitive ability compared to those without the condition. The results were independent of age and gender.
What this means
Mrs Jie Ding from the University of Edinburgh, who helped lead the research (as part of the Edinburgh Type 2 Diabetes Study), said: "These findings suggest that the severity of diabetic retinopathy is independently associated with cognitive dysfunction in people with Type 2 diabetes aged between 60 and 75 years old.
"This can mean either that cerebral microvascular disease, as indexed by retinopathy, may lead to cognitive decrements in old age or that poorer cognitive ability makes diabetes management more difficult, and in turn promotes the development of cerebral microvascular disease.
“It is also possible that a third unidentified factor is causing both diabetic retinopathy and the cognitive changes. The four-year follow-up data of the ET2DS study may clarify the temporal relationship of these associations. The seven neuropsychological tests assessed people's memory for faces, recollection of linear stories, vocabulary, the ability to re-organise a sequence of letters as well as some other cognitive functions.
"The results provide insights into the specific underlying mechanism of cognitive dysfunction in Type 2 diabetes, which is possibly due to a break-down of blood brain barrier (similar to changes in blood-retinal barrier as seen in diabetic retinopathy). From a clinical perspective, cognitive impairment in Type 2 diabetes may therefore be amenable to treatment and preventive strategies targeted at this small vessel disease."
Adding to body of research
Dr Iain Frame, Director of Research at Diabetes UK, said: "Retinopathy is an indicator of cerebral microvascular disease, which is when the small blood vessels in the brain are narrowed or blocked off and lead to a reduction in blood supply to the brain tissues. There is already evidence to suggest that cerebral microvascular disease and Type 2 diabetes may exacerbate the effects of aging on cognitive function.
"This study adds to this body of research as it suggests that diabetic retinopathy is linked to estimated life time cognitive decline in older people with Type 2 diabetes.
"Cognitive decline is the decline of brain functions such as memory, attention, and planning.
"If anyone with diabetes is concerned about their health they should consult their GP or diabetes healthcare professional."
Retinopathy and Type 2 diabetes in the UK
There are 2.35 million people diagnosed with Type 2 diabetes in the UK and up to 500,000 who have the condition but do not know it. Almost two thirds of the 2.35 million people with Type 2 diabetes develop some degree of retinopathy within 20 years of being diagnosed.