Both type 1 and type 2 diabetes were linked to poorer memory and lower psychomotor speed in aging patients, according to research published in Diabetes Care.
“Patients with type 1 diabetes now live long enough to experience cognitive decline,” Gail Musen, PhD, from Joslin Diabetes Center and Harvard Medical School, and colleagues wrote. “During middle age, they show mild cognitive deficits, but it is unknown whether severity increases with aging or whether cognitive profiles are similar to those of age-matched peers with and without diabetes.”
Musen and colleagues examined cognition and associated complications among patients with long-term type 1 diabetes. The researchers compared long-term cognitive outcomes of 82 patients with 50 or more years of type 1 diabetes with 31 age-matched patients with type 2 diabetes and 30 age-matched control patients without diabetes.
Participants completed several questionnaires that assessed general intelligence, executive function, working memory, long-term memory and psychomotor speed. Prior to completion, patients were required to have blood glucose levels that exceeded 4.4 mmol/L.
The researchers found that both patients with type 1 and type 2 diabetes had poorer immediate and delayed recall and psychomotor speed than control patients. A trend toward worse executive function was also observed in patients with diabetes.
Hyperglycemia is more likely to be the cause of cognitive decline in type 1 diabetes than insulin, according to the researchers.
CVD was linked to reduced executive function and proliferative diabetic retinopathy was linked to slower psychomotor speed among patients with 50 or more years of type 1 diabetes.
“Addressing the potential of a growing population with neurodegeneration requires both further study and broader clinical awareness for those aging with type 1 diabetes,” Musen and colleagues concluded. “Efforts should be made to further study this population and screen patient populations and to conduct imaging studies, including those using MRI, to better understand these processes. Ultimately, examination of postmortem specimens may also help clarify the relative roles of hyperglycemia, hypoglycemia, and insulin resistance and enable therapeutic intervention.” – by Alaina Tedesco
The authors report no relevant financial disclosures.