Regional Cerebral Gray Matter Atrophy Is Associated With Cognitive Impairment in Hemodialysis Patients: a Cross-sectional and Longitudinal Voxel-based Morphological Mri Study

Abstract To explore changes of cerebral gray matter volumes (GMV) in hemodialysis patients, the clinical risk factors for GMV changes, and the relationship between GMV changes and neuropsychological tests results. Eighty-eight hemodialysis patients and seventy-six healthy controls (HCs) were recruited in this study. Fifty patients underwent follow-up magnetic resonance, blood biochemical examinations, and neuropsychological test (1.75±0.55 years). Changes in GMV between patients and HCs, longitudinal GMV changes in patients were explored. The clinical risk factors for the longitudinal GMV changes, the correlations between longitudinal GMV changes and neuropsychological tests changes in hemodialysis patients were analyzed. Compared to HCs, the hemodialysis patients had diffusely decreased in GMV (with age, sex, and total intracranial volume [TIV] as covariates, P<0.001, voxel-wise threshold false discovery rate [FDR] corrected). Compared with patients at baseline, regional decreased GMV were found in patients at follow-up (with age, and TIV as covariates, P<0.05, voxel-wise threshold FDR corrected). Increased serum urea, parathyroid hormone levels, and hemodialysis duration were independent risk factors for decreased GMV in hemodialysis patients (all P<0.05, FDR corrected). Hemodialysis patients had lower MMSE (27[26, 29]) and MoCA (22[19.48, 24.04]) scores than HCs (30[29, 30] and 28[26.89, 29]) (all P<0.05). The MMSE scores of hemodialysis patients at follow-up (26[25, 28.5]) were lower than those of patients at baseline (28[25, 29.5]) (P=0.02). The decreased left caudate volumes were positively correlated with reduced MMSE scores in hemodialysis patients (rs=0.437, P=0.033). Hemodialysis patients had diffused GM atrophy over time, which was related to cognitive impairment.