The term "mild cognitive impairment" describes a transitional stage between normal ageing and dementia, the researchers explain in a recent report. Previous studies have shown a link between mild cognitive difficulties and diabetes.
Poor control of blood sugar over time may lead to loss of brain cells, and diabetes increases the risk of cardiovascular disease and stroke, which also may increase the risk of cognitive impairment.
Read: What is diabetes?
Dr Rosebud O. Roberts and colleagues studied 1 969 people who were between 70 and 89 years old and free of dementia in 2004. A total of 356 of them were diabetic.According to the team, rates of diabetes were similar among the 329 individuals with mild cognitive impairment (20.1 percent) and the 1 640 individuals without mild cognitive impairment (17.7 percent).
Diabetes at an early age
However, mild cognitive impairment was associated with diagnosing diabetes before age 65, having diabetes for 10 years or longer, being treated with insulin and having diabetes complications.
Read: Symptoms of diabetes
Severe diabetes mellitus is more likely to be associated with chronic high blood sugar, which, in turn, increases the likelihood of disease in the small blood vessels of the brain and may contribute to brain cell damage and cognitive impairment, the investigators suggest.
That individuals with the eye disease known as diabetic retinopathy were twice as likely to have mild cognitive impairment supports the theory that diabetes-related damage to blood vessels in the brain may contribute to the development of cognitive problems, they say.
Diabetes and the brain
Diabetes and the eyes
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