Diabetes Linked to Worse Cognition in Aging Seniors

A study published in Diabetes Care associated type 1 and type 2 diabetes with poorer memory and reduced psychomotor speed in aging seniors, reports Healio . "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," says Harvard Medical School's Gail Musen. Her team examined cognition and associated complications among people with long-term type 1 diabetes, comparing long-term cognitive outcomes of 82 subjects with 50 or more years of type 1 diabetes with 31 age-matched individuals with type 2 diabetes and 30 age-matched non-diabetic controls. Before the study was completed, participants had to have blood glucose levels that exceeded 4.4 mmol/L. Both participants with type 1 and type 2 diabetes demonstrated poorer immediate and delayed recall and psychomotor speed than controls, while worsening executive function also was seen in diabetic subjects. The researchers determined hyperglycemia to be a more likely cause of cognitive decline in type 1 diabetes than insulin, and cardiovascular disease was tied to reduced executive function while proliferative diabetic retinopathy was linked to slower psychomotor speed among participants with 50 or more years of type 1 diabetes. "Efforts should be made to further study this population and screen ... populations and to conduct imaging studies, including those using MRI, to better understand these processes," the team recommends. "Ultimately, examination of postmortem specimens may also help clarify the relative roles of hyperglycemia, hypoglycemia, and insulin resistance and enable therapeutic intervention."