Higher Insulin Levels May Contribute to Alzheimer's
Study found elevated levels increased inflammation
MONDAY, Aug. 8, 2005 (HealthDay News) -- Elevated insulin levels may contribute to the development of Alzheimer's disease, and investigators hope this new finding will lead to more effective treatment strategies, according to a report in the Aug. 8 issue of the Archives of Neurology.
Researchers at the University of Washington in Seattle raised blood insulin levels in 16 healthy older adult volunteers and then measured changes in the volunteers' levels of inflammatory markers and beta-amyloid (a protein associated with Alzheimer's disease) in their cerebrospinal fluid and plasma.
"Moderate peripheral hyperinsulinemia (increased levels of insulin) provoked striking increases in CNS (central nervous system) inflammatory markers," the study authors wrote. "Our findings suggest that insulin-resistant conditions such as diabetes mellitus and hypertension may increase the risk for Alzheimer's disease, in part through insulin-induced inflammation."
The research team concluded: "Although this model has obvious relevance for diabetes mellitus, hyperinsulinemia and insulin resistance are widespread conditions that affect many nondiabetic adults with obesity, impaired glucose tolerance, cardiovascular disease and hypertension. Our results provide a cautionary note for the current epidemic of such conditions, which, in the context of an aging population, may provoke a dramatic increase in the prevalence of [Alzheimer's disease]."
The U.S. National Institute on Aging has more about Alzheimer's disease.