Pseudobulbar Affect in Dementia: Neuropsychiatric Associations and Subtype Differences

Background: Pseudobulbar affect (PBA) is a disorder characterized by involuntary episodes of crying or laughing that are disproportionate or inappropriate to the social context. It is frequently observed in neurological disorders, including dementia, but often remains underrecognized due to diagnostic challenges. This study aimed to determine the prevalence of PBA in dementia patients, explore its relationship with neuropsychiatric symptoms, and assess differences across dementia subtypes. Methods: This single-center, cross-sectional study included 212 participants (159 dementia patients and 53 healthy controls). Participants were assessed using the Center for Neurologic Study-Lability Scale (CNS-LS), Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), Geriatric Anxiety Scale (GAS), and Apathy Evaluation Scale (AES). Statistical analyses included independent t-tests, one-way ANOVA, and Pearson correlation tests. Results: The prevalence of PBA among dementia patients was 53%, significantly higher than in the healthy control group (p = 0.021). PBA scores were highest in vascular dementia (VD) and frontotemporal dementia (FTD) patients, with significantly lower scores in Alzheimer’s disease (AD) and Lewy body dementia (LBD) (p < 0.001). A significant positive correlation was found between PBA and both depression (GDS) and anxiety (GAS), while a borderline negative correlation was observed with cognitive function (MMSE). No significant relationship was detected between PBA and apathy (AES). Additionally, caregivers reported laughing or crying episodes in 70% of dementia patients, despite the underrecognition of PBA in clinical practice. Conclusion: PBA is a prevalent but underdiagnosed neuropsychiatric symptom in dementia, with its occurrence varying across subtypes. VD and FTD patients exhibit the highest PBA scores, whereas AD and LBD patients show similar scores to healthy controls. The strong association between PBA, depression, and anxiety highlights the need for systematic screening in dementia care. Raising awareness and conducting further research on the pathophysiology of PBA may improve diagnosis and treatment strategies, ultimately enhancing patient outcomes.