Factors associated with brain white matter damage in type 2 diabetes mellitus: a tract-based spatial statistics study

The pathogenesis and related factors of central nervous system abnormality in patients with type 2 diabetes mellitus (T2DM) have always been the focus of clinical research.To compare and analyze the area of white matter (WM) damage in patients with T2DM based on their level of hemoglobin A1C (HBA1c) and discuss any related factors.Based on their levels of HBA1c, 87 patients with T2DM were divided into three groups (Group B, C, or D), of which 29 non-diabetic volunteers served as the control group (Group A). DTI data analysis was based on tract-based spatial statistics (TBSS). The obtained parameters were compared among each group and the relevant clinical factors were analyzed.For age, sex, mini-mental state examination (MMSE), and Montreal Cognitive Assessment (MoCA) scores, there were no statistically significant differences among groups. For fractional anisotropy (FA) and radial diffusivity (RD) of WM, there were statistically significant differences (P < 0.05, two-tailed, FWE corrected) in the local area of corpus callosum, corona radiate, superior longitudinal fasciculus, etc. Most of these were significantly correlated with body mass index (BMI), left systolic blood pressure (SBP_L), and β2 microglobulin.Before the cognitive function was obviously impaired, abnormalities of FA and RD had been found in the corpus callosum, corona radiate, and upper fasciculus in patients with T2DM, which suggested that the damage mainly occurred in the myelin sheath of WM and may be related to systemic vascular damage.