Diabetes, Insulin Resistance Tied to Alzheimer's Pathology

Those with type 2 diabetes, insulin resistance may be more likely to develop neuritic plaques

THURSDAY, Aug. 26 (HealthDay News) -- Individuals with type 2 diabetes and insulin resistance may be at an increased risk of developing brain plaques that are linked to Alzheimer's disease, according to a study published online Aug. 25 in Neurology.

T. Matsuzaki, M.D., of Kyushu University in Fukuoka, Japan, and colleagues evaluated specimens from a series of 135 autopsies (74 men and 61 women) performed between 1998 and 2003. The subjects had undergone a 75-g oral glucose tolerance test in 1988. The researchers measured diabetes-related factors to assess the association between these factors and the pathology of Alzheimer's disease.

After adjustment for age, sex, systolic blood pressure, total cholesterol, body mass index, habitual smoking, regular exercise, and cerebrovascular disease, the investigators found that increased levels of two-hour post-load plasma glucose, fasting insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) were associated with an increased risk for neuritic plaques. However, neurofibrillary tangles were not found to be associated with diabetes-related factors. The combined presence of hyperglycemia and APOE genotype was associated with an increased risk for neuritic plaque formation, with similar enhancement found for hyperinsulinemia and high HOMA-IR.

"The study by Matsuzaki et al supports the hypothesis that insulin resistance and type 2 diabetes is causally related to a higher risk of dementia, including Alzheimer's disease," writes the author of an accompanying editorial.

One author disclosed financial ties to multiple pharmaceutical companies.

Full Text (subscription or payment may be required)
Editorial (subscription or payment may be required)

Physician's Briefing