Eating Behavior Differences Across Dementia Diagnoses: The Roles of Behavioral Symptoms and Anticipatory Physiological Responses

Objective: To determine how behavioral symptoms and impairment of the preparatory physiological response contribute to disordered eating behaviors in dementia, particularly frontotemporal dementia (FTD) and Alzheimer’s disease (AD). Methods: This secondary analysis utilizes data from 242 patients (191 FTD, 51 AD) who took part in a collaborative study between the University of California, Berkeley, and the University of California, San Francisco. Preparatory physiological responses were measured as heart rate increases from a baseline to an instruction period, when participants were informed that they were about to watch an emotional film. Behavioral symptoms, including eating behaviors, were assessed using the Neuropsychiatric Inventory (NPI), a 12-item questionnaire completed by caregivers. Results: Preparatory physiological response impairment was weakly correlated with higher NPI eating abnormality scores but did not significantly mediate the relationship between these scores and dementia diagnosis. Five behavioral symptoms, however, emerged as significant mediators. From greatest to least in strength, these are: disinhibition, aberrant motor symptoms, apathy, euphoria, and sleep disturbances. Discussion: These findings suggest that behavioral symptoms, rather than anticipatory physiological responses, play a dominant role in eating behavior differences between dementia diagnoses. While physiological mechanisms may still contribute to eating behaviors in dementia, this study highlights the need for further research into cephalic response impairments. Future works should explore direct measures of cephalic functioning, probe other physiological mechanisms, and consider behavioral interventions to manage disordered eating in dementia.