Higher Insulin Resistance is Associated with Lower Myelin Content in Women

Motivation: Emerging evidence implicates insulin and its signaling pathways in Alzheimer's disease (AD) pathogenesis, with neuroimaging studies revealing associations between insulin resistance (IR) and alterations in brain regions vulnerable to early AD. However, the effects of IR on white matter (WM) microstructure, specifically myelination, remain unclear. Goal(s): To investigate the relationship between IR and myelin content. Approach: We perform multiple linear regression between IR and myelin, probed using myelin water fraction (MWF) or fractional anisotropy (FA) imaging. Results: Women showed significant negative correlations between IR and MWF in three major brain regions, while men showed no significant correlations. Impact: This research highlights the connection between metabolic conditions and white matter integrity in women. It also underscores that MWF offers a more sensitive measure of microstructural differences as compared to FA.