Disrupted white matter microstructural integrity of type 2 diabetes mellitus with mild cognitive impairments.

Type 2 diabetes mellitus (T2DM) is frequently complicated by cognitive impairments. We aim to investigate white matter microstructural changes in T2DM with mild cognitive impairments(T2DM-MCI). Sixteen T2DM-MCI patients, thirty-six T2DM with normal cognition (T2DM-NC), and twenty-nine healthy controls (HCs) were enrolled in this study. Neurite Orientation Dispersion and Density Imaging (NODDI) and cognitive assessment were obtained from all participants. White matter microstructural alterations in T2DM-MCI were evaluated with NODDI. Furthermore, correction analysis was performed to assess the relationship between white matter microstructural alterations and cognitive performance. Compared with HC, T2DM-MCI and T2DM-NC showed lower neurite density index (NDI), higher orientation dispersion index (ODI) and free water fraction (FWF) in multiple white matter fibers such as inferior fronto-occipital fasciculus, superior thalamic radiation and corticospinal tract. T2DM-MCI also showed increased ODI and FWF compared with T2DM-NC. In addition, white matter microstructural changes showed significant correlation with cognitive scores and blood glucose level in the T2DM-MCI group. White matter microstructural alterations correlated with cognitive impairments in T2DM-MCI, deepening our understanding of the neural basis of early cognitive impairment in T2DM.