Effects of Change in Insulin Resistance and Systemic Inflammation on Brain Structure and Function

A growing body of evidence suggests that obesity is associated with alterations in brain
structure and cognitive impairment. Mid-life obesity is a risk factor for Alzheimer's disease
and vascular dementia. The mechanisms underlying obesity related decline in cognitive
function are not fully understood. The long-term goal of this research is to identify how
obesity, insulin resistance (IR), and their treatment impact brain structure and function.
The investigators propose that IR and obesity related inflammation are two modifiable factors
that affect neuronal integrity and lead to cognitive dysfunction. In this proposal,
investigators will test two hypotheses: 1) among obese patients planning to undergo bariatric
surgery (specifically vertical sleeve gastrectomy), baseline IR and systemic and brain
markers of inflammation will inversely correlate with performance on cognitive testing and
correlate with abnormalities in brain structure and 2) following bariatric surgery subjects
who experience the greatest reduction in IR and obesity related inflammation will have the
greatest improvement in cognitive function and brain structure. To address these hypotheses,
investigators will use a comprehensive battery of tests to evaluate cognition and state of
the art magnetic resonance imaging (MRI) techniques to assess brain structure and
neurochemistry before and six months after bariatric surgery.

Inclusion Criteria:

Obese Group

- Undergoing VSG-type bariatric surgery

- BMI > 30

- Current weight less than 400 lbs

Non-Obese Group

- Age 30-50

- BMI < 25

Exclusion Criteria:

Both Groups

- History of type 1 or type 2 diabetes

- History of stroke

- History of epilepsy

- History of Neurosurgical procedures

- Past or current history of severe psychiatric illness

- Pass or current history of alcohol or substance abuse

- Absence of metallic substances in body or ability to remove before imaging procedure

- History of claustrophobia or known inability to tolerate MRI

- Inability to consent