Correlation of white matter microstructural changes with executive function impairment in patients with white matter lesions / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To explore abnormal microstructural changes of white matter in patients with white matter lesions(WML) using diffusion tensor imaging(DTI), and to determine the association of such abnormalities of DTI parameters with executive function.Methods:Totally 34 patients with WML were recruited from the department of Neurology, Beijing Tiantan Hospital, Capital Medical University from March 2012 to May 2019.All patients with WML were scored with Hamilton depression scale (HAMD) and Hamilton anxiety scale (HAMA), and assessed with Montreal cognitive assessment (MoCA) and clinical dementia rating(CDR). They were divided into WML-cognitive normal group, WML-vascular cognitive impairment-non dementia group and WML-Dementia group.The Stroop color and word test (SCWT), trail making test-A (TMTA), digit symbol test and verbal fluency test were carried out to evaluate executive function.In addition, the healthy elderly without WML lesions were selected as the control group after they were examined by MRI, and all brains of the subjects went through DTI with Siemens 3.0 T MR.The data were collected and analyzed by voxel based analysis (VBA). The anisotropy and mean diffusion coefficient of DTI in the region of interest (ROI) and other regions in the brain were studied in the four groups, and their correlation with scores of executive function in WML patients was analyzed.Results:(1)In these executive function test, there were significant differences between the patients with cognitive impairment (WML-VAD group, WML-VCIND group) and normal cognition group(WML-CN group, NC group), such as SCWT(B)(65.54±6.24 vs 43.67±0.95, 76.75±2.13 vs 43.67±0. 95, 65.54±6.24 vs 43.66±1.81, 76.75±2.13 vs 43.66±1.81), SCWT(C)(88.58±6.76 vs 61.63±1.31, 96.37±1.47 vs 61 63±1.31, 88.58±6.76 vs 66.31±8.19, 96.37±1.47 vs 66.31±8.19), TMTA(40.47±2.76 vs 30.92±0.47, 44.24±1.43 vs 30.92±0.47, 44.24±1.43 vs 31.99±2.07, 40.47±2.76 vs 31.99±2.07), TMTB(88.66±6.55 vs 80.34±0.61, 96.70±1.72 vs 80.34±0.61, 88.66±6.55 vs 83.10±5.91, 96.70±1.72 vs 83. 10±5.91), Digit Symbol Test(39.25±5.63 vs 47.00±2.55, 31.27±3.93 vs 47.00±2.5, 39.25±5.63 vs 48.86±4.34, 31.27±3.93 vs 48.86±4.34) and Verbal Fluency Test(8.94±1.00 vs 11.71±0.47, 6.64±0.81 vs 11.71±0.47, 8.94±1.00 vs 10.86±0.69, 6.64±0.81 vs 10.86±0.69) scores ( P<0.05); In the patients with cognitive impairment, there were significant differences between WML-VAD group and WML-VCIND group, such as SCWT(B), SCWT(C), TMTA, TMTB, digit symbol test and verbal fluency test scores ( P<0.05); There were significant differences between WML-CN patients and NC group in the scores of SCWT (C), verbal fluency test( P<0.05). (2)FA values in the genu of corpus callosum and the inferior longitudinal fasciculus were negatively correlated with the time of SCWT (B), SCWT (C) and the TMTA( r=-0.436--0.471), but positively correlated with the scores of digit symbol test and verbal fluency test( r=0.428-0.573). MD values in the genu of corpus callosum, the superior/inferior longitudinal fasciculus and the inferior fronto-occipital fasciculus were positively correlated with the time of SCWT (B), SCWT (C) and TMTA( r=0.432~0.609), but negatively correlated with the scores of digit symbol test and verbal fluency test( r=-0.424--0.630, all P<0.003125 after emendation). Conclusion:The executive function of patients with WML-Dementia decreases significantly.The more serious the damage of white matter microstructure, the more serious the damage of executive of function.