Characteristics of cognitive⁃neuropsychiatric behavioural features and 18F⁃FDG PET images in progressive supranuclear palsy and behavioral variant frontotemporal dementia

Abstract

Objective To compare the characteristic of cognitive function, behavioral and psychological symptoms and different cerebral glucose metabolism between patients with progressive supranuclear palsy(PSP) and behavioral variant frontotemporal dementia (bvFTD). Methods Twenty PSP patientsand 65 bvFTD patients wererecruited afterfollow⁃upfor morethan 36 months. The Mini⁃Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), Activities of Daily Living Scale (ADL) and Neuropsychiatric Inventory (NPI) were used to evaluate the degree of cognitive impairments, the abilities of daily living, and behavioral and psychological symptoms, respectively. Part of the atypical patients, including 18 bvFTD and 17 PSP, were examined by 18F⁃FDG PET to analyze the difference of cerebralglucose metabolism between 2 groups. Results The MMSE scores(P=0.046)and MoCA scores (P=0.009) were higherin PSP groupthan bvFTD group. A detailanalysisof MoCA sub⁃item showedthe scores of naming (P=0.038), language (P=0.006), abstraction (P=0.011), delayed recall (P=0.001) and orientation (P=0.004) were higher in PSP group than those in bvFTD group, while the score of executive function/visuospatial ability and attention had no difference between both 2 groups. And there was no significant difference in ADL score and NPI score between 2 groups. In respect of the 12 items of NPI, the 16 PSP patients (88.89%) and 63 bvFTD patients (96.92%) had one or more neuropsychiatric behavior symptoms, respectively. The incidence of agitation (P=0.015) and irritability (P=0.036) was significantly lower in PSP group than in bvFTD group, while the incidence of apathy (P=0.047) and depression (P= 0.024) was higher than in bvFTD group. The 18F⁃FDG PET imaging of all the patients in 2 groups presented decreased metabolism in frontal lobe, insular lobe and caudate nucleus, and PSP group also showed hypometabolism in thalamus and midbrain. Conclusions The PSP patients showed obvious cognitive impairment and psychological symptoms, combined with 18F⁃FDGPET imaging, which were helpful for distinguishing PSP from bvFTD.

DOI：10.3969/j.issn.1672⁃6731.2020.09.010