Multimodal MRI of choroid plexus volume, DTI-ALPS, and white matter microstructure in type 2 diabetes mellitus

Abstract

Objective To investigate differences in choroid plexus volume (CPV), diffusion tensor image analysis along the perivascular space (DTI-ALPS) indices, peak width of skeletonized mean diffusivity (PSMD), and Mini-Mental State Examination (MMSE) scores between patients with type 2 diabetes mellitus (T2DM) and healthy controls, and to explore pairwise associations among diabetes duration, PSMD, normalized total CPV, total DTI-ALPS, and MMSE within the T2DM group. Methods This retrospective cross-sectional study included 31 patients with T2DM and 31 healthy controls (HCs). All participants underwent 3.0-T MRI and MMSE assessment. General linear models were used to compare normalized CPV, DTI-ALPS indices, PSMD, and MMSE scores between groups, adjusting for age, sex, body mass index, and years of education. Within the T2DM group, exploratory partial correlations were performed among diabetes duration, PSMD, normalized total CPV, total DTI-ALPS, and MMSE, controlling for the same covariates. The resulting 10 pairwise associations were corrected together using the Benjamini-Hochberg false discovery rate (FDR) procedure. Results Compared with HCs, patients with T2DM showed greater normalized total and bilateral CPV, lower total DTI-ALPS, higher PSMD, and lower MMSE scores (all P FDR < 0.05). Among the 10 exploratory associations, only the positive association between diabetes duration and PSMD remained significant after FDR correction ( partial r = 0.566, P = 0.002, P FDR = 0.021). The inverse association between normalized total CPV and total DTI-ALPS was nominally significant ( partial r = −0.412, P = 0.033) but did not survive FDR correction ( P FDR = 0.163). Conclusion Patients with T2DM showed differences in CPV, DTI-ALPS, PSMD, and MMSE scores. Longer diabetes duration was associated with higher PSMD after FDR correction, whereas the CPV–DTI-ALPS association did not survive multiple-comparison correction. These findings highlight the value of multimodal MRI for characterizing brain involvement in T2DM.