Hyperinsulinemia and type 2 diabetes (T2D) are important potential risk factors for cognitive
decline and Alzheimer's disease (AD). Two thirds of the US adult population are at risk for
hyperinsulinemia and T2D, and half of the population 85 years and older have AD. Peripheral
hyperinsulinemia can impair the clearance of amyloid beta in the brain, the main culprit in
AD. Thus, the investigators hypothesize that lowering peripheral insulin in overweight
persons with amnestic mild cognitive impairment (AMCI), a transition state between normal
cognition and AD, can decrease the risk of cognitive decline and progression to AD. The
investigators propose to conduct a phase II double blinded placebo controlled randomized
clinical trial of metformin, a safe and effective medication that prevents hyperinsulinemia
and diabetes, to test this hypothesis among 80 overweight persons aged 55 to 90 years with
AMCI. The main outcome of the study will be changes in performance in a memory test (total
recall of the Selective Reminding Test) and the Score a test of general cognitive function
used in clinical trials (the Alzheimer's Disease Assessment Scale-cognitive subscale
(ADAS-Cog)). Another aim is to compare brain function in an area affected by Alzheimer's
disease between the metformin and placebo group mean changes from beginning to end among 40
participants using a PET scan.
Phase:
Phase 2
Details
Lead Sponsor:
Columbia University
Collaborators:
Institute for the Study of Aging (ISOA) National Institute on Aging (NIA)