Association between Cognitive and Neuropsychological Features of Pisa Syndrome in Dementia with Lewy Bodies

Zhou Su¹Jun Kuai²Tingting Yi¹Hao Wu³Jinghuan Gan⁴Zhihong Shi³Shuai Liu³Yong Ji^3*

• ¹Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xin xiang, China
• ²Department of Gastroenterology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
• ³Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China
• ⁴Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing, China

Background: Pisa syndrome (PS), characterized by trunk lateral flexion, remains rarely reported in dementia with Lewy bodies (DLB). While its pathogenesis is multifactorial, underlying mechanisms are not fully understood. Given the established link between postural control and cognition in aging populations, cognitive impairment has been implicated in PS development. Notably, no studies have investigated the potential contributions of cognitive dysfunction and neuropsychiatric symptoms to the development of PS in DLB patients or its relationship with caregiver burden. Methods: This study included 35 DLB patients with PS and 183 DLB patients without PS. We compared cognitive function across different domains using the Montreal Cognitive Assessment (MoCA) and its subdomains, and the Clock Drawing Test (CDT), and dementia severity using the Clinical Dementia Rating (CDR). The prevalence and severity of neuropsychiatric symptoms and caregiver distress were measured using the Neuropsychiatric Inventory (NPI) and Zarit Burden Interview (ZBI). Results: The patients in the PS group showed significantly worse performances in attention (p = 0.012), visuospatial/executive abilities (p = 0.013), and lower scores on the CDT (p = 0.007). The PS group demonstrated significantly elevated NPI total scores (p = 0.008), with higher frequency and severity of delusions (p = 0.006 and p = 0.008), hallucinations (p = 0.004 and p < 0.001), and aberrant motor behaviors (p = 0.020 and p = 0.006). The PS group also had significantly higher ZBI scores (p = 0.023). Caregivers in the PS group reported greater distress and burden related to delusion (p = 0.030), hallucination (p < 0.001), anxiety (p = 0.020), aberrant motor behavior (p = 0.001), and sleep disturbance (p = 0.009). Conclusion: Our study reveals that PS in DLB is associated with specific deficits in attention and visuospatial/executive function, alongside more severe neuropsychiatric symptoms. These findings highlight the need for comprehensive management targeting both postural control and neuropsychiatric issues to alleviate caregiver burden. Future longitudinal studies are warranted to clarify the causal nature of these relationships.