Research Area
Aging

Grant Type
Start-Up

Year
2007

Abstract

The frequency of type II diabetes (DM, also known as adult-onset diabetes) and insulin resistance (IR), the presumed precursor of DM, have increased sharply in the United States during the past decade. In people with IR, their ability to regulate glucose metabolism is damaged. There is growing evidence that both IR and DM impact brain health as patients age, based on epidemiological studies where patients with Alzheimer’s disease have higher rates of DM. Even DM occurring in mid-life may increase the risk for developing Alzheimer’s disease in late life. IR is also identified as a risk for dementia in HIV patients

In this study, we will determine if the neuropsychological and anatomical characteristics of cognitive problems related to IR are different when IR is superimposed on groups of individuals at risk for different types of dementia. One study group will combine normal controls and people with Mild Cognitive Impairment (MCI). A comparison group will comprise of HIV patients over 60 years old. All individuals will receive comprehensive neuropsychological testing, a complete neurological examination, oral glucose tolerance testing (to quantify IR), and brain MRI. We anticipate that patients with HIV will have more difficulty in tests of psychomotor speed should they also have IR, while our normal/MCI groups will experience more problems in learning/memory with greater degrees of insulin resistance. We also expect IR to relate to smaller total brain volumes among all participants and, particularly, to smaller hippocampal volumes.