AUTHOR=Chiu Pai-Yi , Wei Cheng-Yu , Hung Guang-Uei , Wu Shey-Lin 

TITLE=Motor Dysfunction Questionnaire and Dopamine Transporter Imaging Composite Scale Improve Differentiating Dementia With Lewy Bodies From Alzheimer's Disease With Motor Dysfunction

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=Volume 13 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2021.709215

DOI=10.3389/fnagi.2021.709215

ISSN=1663-4365

ABSTRACT=Objective: Characteristic parkinsonism is the major comorbidity of dementia with Lewy bodies (DLB). We aimed to differentiate DLB from Alzheimer’s disease (AD) with motor dysfunction using a composite scale with a characteristic motor dysfunction questionnaire and dopamine transporter  (DAT) imaging. It could help detect DLB easily in healthcare settings without movement disorder specialists. Methods: This was a two-phase study. In the design phase, seven questions were selected and composed of a novel motor dysfunction questionnaire (MDQ). In the test phase, all participants with DLB, AD, or non-dementia control (ND) completed the dementia and parkinsonism survey, the novel designed questionnaire, DAT imaging, and composite scales of MDQ and DAT. The cut-off scores of the MDQ, semi-quantitative analysis of the striato-background ratio (SBR) and visual rating of DAT, and the composite scale of MDQ and DAT for discriminating DLB from AD or ND were derived and compared. Results: A total of 277 participants were included in this study (126 with DLB, 86 with AD, and 65 with ND). Compared to the AD or ND groups, the DLB group showed a significantly higher frequency in all seven items in the MDQ as well as a significantly lower SBR. For discrimination of DLB from non-DLB with MDQ, SBR, and composite scale, cut-off scores of 3/2, 1.37/1.38, and 6/5 were suggested for the diagnosis of DLB with sensitivities/specificities of 0.91/0.72, 0.91/0.80, and 0.87/0.93, respectively. The composite scale significantly improved the accuracy of discrimination compared with either the MDQ or SBR. Conclusion: Our study showed that the novel designed simple questionnaire was a practical screening tool and had similar power to DAT scanning to detect DLB. The questionnaire can be applied in clinical practice as well as population studies for screening DLB. In addition, the composite scale of MDQ and DAT imaging further improved the diagnostic accuracy, indicating the superiority of the dual-model diagnostic tool.