Insulin Resistance is Associated with Smaller Brain Volumes in a Preliminary Study of Depressed and Obese Children.

Objective: During childhood, the brain can consume up to 65% of total calories, and a steady supply of the brain's main fuel glucose needs to be maintained. Although the brain itself is not dependent on insulin for the uptake of glucose, insulin plays an important role in energy homeostasis. Thus, the risk for insulin resistance during brain development may negatively impact the whole brain volume. Methods: We investigated the link between the insulin resistance and the whole brain volume as measured by structural Magnetic resonance imaging (MRI) in 46 unmedicated depressed and overweight youths between the ages of 9 and 17 years. Results: Smaller whole brain volumes were associated with insulin resistance independent of age, sex, depression severity, body mass index, socioeconomic status, Tanner Stage, and Intelligence quotient (IQ) (r = 0.395, P = .014) Conclusions: There may be a significant cost for developing insulin resistance on the developing brain. Disentangling the precise relationship between the insulin resistance and the developing brain is critical.