Glucose intolerance, diabetes or insulin resistance were not associated with the pathological characteristics of Alzheimer's or cerebral amyloid load in Baltimore's longitudinal study on aging (BLSA).
Glucose intolerance and diabetes could be Alzheimer's risk factors, but scientific evidence is contradictory, the authors explain in Jama Neurology.
The team of the neurologist Richard O'Brien, of the Bayview Medical Center of Johns Hopkins, Baltimore, Maryland, said that the intensity of the evaluations during the BLSA, including the oral test of glucose tolerance (POTG) in series, converts it intoAn ideal study to analyze the effects of glucose intolerance and insulin resistance in amyloid accumulation and the formation of neurofibrillar olls in the brain.
The authors studied two groups of patients: A 197 with two or more POTG and postmortem brain studies and 53 living patients with two or more POTG and PET with amyloid detection agent (compound B of Pittsburgh).
The team could not detect significant correlations between the determinations of the cerebral pathology of the AlzheimerPOTG during the 22 years of monitoring.
Nor did he find a relationship between the clinical diagnosis of dementia and hyperglycemia or hyperinsulinemia.
"Our results coincide with other studies that had not identified an association between diabetes and Alzheimer's, and we prolong these observations to hyperglycemia and insulin resistance," says the team.
O'Brien said: "Our findings are fully compatible with medical literature, it is literature that was left aside in the last stir around diabetes and Alzheimer's."
And he cited a September 2012 entrance in a blog in the New York Times that favored that stir: "Is Alzheimer's diabetes type 3?"
Instead, he pointed out that vascular disease, instead of amyloid pathology, could explain the association between diabetes and cognitive deterioration detected in some studies.
"Many evidence suggests that cardiovascular disease favors the appearance of dementia in older adults," he explained.
"Diabetics need to treat their vascular risk factors aggressively, but it is unlikely that diabetes will increase the portion associated with the Alzheimer's from the risk factors of dementia," he added.
Dr. David M. Holtzman, head of the Washington University Neurology Department, St. Louis, Missouri, and who did not participate in the study, considered it "well done" and clarified that he cannot say if diabetes predisposes to develop Alzheimer's.
"But the conclusions we can get are few because most of the people studied did not have diabetes. In fact, most did not even have prediabetes," he added.
The National Health Institutes and the Burroughs Wellcome Fund for Translation Research financed the study.The authors declared not having conflicts of interest.