AUTHOR=Xue Xiaofan , Huang Anqi , Zeng Jingrong , Song Haixia , Xing Yingqi , Chan Piu , Xu Erhe , Zhou Lichun 

TITLE=The mechanism of impaired delayed recall verbal memory function in Parkinson's disease with orthostatic hypotension: a multiple imaging study

JOURNAL=Frontiers in Neurology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1149577

DOI=10.3389/fneur.2023.1149577

ISSN=1664-2295

ABSTRACT=Orthostatic hypotension (OH) frequently accompanies autonomic dysfunction and is an important risk factor for cognitive impairment in Parkinson’s disease (PD). However, the association between different cognitive functions and OH in PD patients is not yet fully understood. We aimed to evaluate the score of different cognitive domains and multiple parameters by using different imaging techniques on PD patients with or without OH. A total number of 31 PD patients with OH (n=20) and without OH (n=11) were recruited from the department of Neurology, Beijing Xuanwu Hospital for this study. All patients underwent beat-to-beat non-invasive blood pressure recordings and active standing test to evaluate neurogenic OH, and global neuropsychological test to assess cognitive function. All patients underwent dynamic cerebral autoregulation (dCA) Measurement, brain magnetic resonance imaging (MRI) and brain 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). The results showed that OH patients had poor delayed recall verbal memory comparing with the PD patients without OH (1.75±1.59 vs 3.10±1.73, p=0.042). DCA test indicated a significant difference on the right very low-frequency (VLF) gain between two groups (1.27±0.17 vs 1.10±0.26, p=0.045) and brain 18F-FDG PET/CT indicated a significant difference on the SUV (right medial temporal lobe) to SUV (occipital lobe) ratio (0.60±0.08 vs 0.67±0.11, p=0.049). Meanwhile, these two imaging parameters were negatively correlated (p<0.001). Also, the score of delayed recall verbal memory in OH group was positively correlated with the right medial temporal lobe to occipital lobe ratio (p<0.001) and was negatively correlated with the right VLF gain (p=0.023). PD with OH patients had poor delayed recall memory, which might be caused by the decreased metabolic of specific medial temporal lobe due to the impaired dCA ability.