[Characteristics of cognitive impairment and the resting state functional MRI in patients with leukoaraiosis]

Objective: To investigate the features of cognitive impairment and potential physiopathologic mechanism using neuropsychological assessment and resting state functional magnetic resonance imaging (rs-fMRI) in patients with leukoaraiosis (LA). Methods: A total of 13 patients with LA (LA group) and 13 healthy controls (NC group) from Shanxi Provincial People's Hospital between January and June 2016 were recruited. The two groups were matched for age, sex, education, and vascular risk factors. All the subjects underwent neuropsychological assessment and the scan of rs-fMRI. The neuropsychological scores and the brain areas had significant differences of cerebral spontaneous activity in resting state of the two groups were compared, and the relationship between the scores and the amplitude of low frequency fluctuation (ALFF) were evaluated in these areas. Results: LA group was associated with comprehensive cognitive impairment, including minimum mental state examination (MMSE) (LA group: 23.3±10.7 vs NC group: 29.7±0.6), montreal cognitive assessment (MoCA) (22.7±10.7 vs 29.5±0.7), digit span test (DS) forwards (6.5±3.2 vs 8.7±1.1) and backwards (4.2±2.2 vs 6.2±0.9), trail making test (TMT) part A (168±136 vs 47±10), immediate memory (6.1±3.5 vs 11.0±2.2) and delayed memory (4.7±2.8 vs 11.0±2.4) of auditory verbal learning test (AVLT), Stroop B (60±34 vs 32±7) and C (127±72 vs 48±12), verbal similarity test (16.5±8.1 vs 23.1±2.5) (all P<0.05). Compared with the NC group, patients with LA showed decreased ALFF in areas of the right posterior cingulate cortex (PCC), precuneus_R, cuneus, postcentral_R, precentral_R, calcarine_R (all P<0.05). After adjustment for the influences of age, sex and education, the correlation analysis showed that right PCC, precuneus_R, cuneus, postcentral_R, etc, were closely related with cognitive impairment. Conclusions: Patients with LA exhibits significant cognitive impairment, such as executive function, memory, attention and information processing speed. And cognitive impairment of LA is related to abnormal cerebral spontaneous activity, especially in areas of right PCC, precuneus_R, cuneus, etc.