Behavioral and psychological symptoms (BPS; e.g., hallucinations, apathy) frequently manifest in several forms of dementia and are often critical considerations for accurate diagnosis and effective interventions with this clinical population. BPS are commonly measured in clinical and research contexts by the Neuropsychiatric Inventory Questionnaire (NPI-Q), a 12-item, informant-based questionnaire which assesses typical BPS associated with various dementia syndromes. A recent study determined a robust 4-factor structure characterized by “psychosis,” “mood,” “behavioral activation,” and “behavioral suppression/somatic disturbance” symptoms best fit the NPI-Q, but no research has quantified the extent to which these four NPI-Q factors may differ across etiologies of dementia. Given dementia is a notably heterogenous syndrome, the objective of this study was to examine these four NPI-Q factors among different types/etiologies of dementia to assess consistency of symptom profiles.

The sample consistent of data from 45,033 informants (i.e., family member or other loved one involved in patients’ life) who completed the NPI-Q during their first visit to an Alzheimer’s Disease Research Center (ADRC) extracted from the National Alzheimer’s Coordinating Center (NACC) database. Study groups were established as: 1) Alzheimer’s disease; 2) cognitively normal; 2) motor Frontotemporal dementia; 3) non-motor Frontotemporal dementia; 3) Lewy Body dementia; 4) other medical disorder; 5) other neurological disorder; 6) psychiatric disorder; 7) vascular Cognitive Impairment. Analyses of variance assessed for differences between dementia etiologies using on the 4-factor NPI-Q model (i.e., psychosis, mood, behavioral activation, and behavioral suppression/somatic disturbance) identified by Gonzalez and colleagues (2023) was assessed.

The ANOVA revealed a significant effect of diagnostic group on the following: 1) individuals diagnosed with Lewy Body had higher scores (M = .0879, SD = 1.397) on indices assessing psychosis compared to the other groups (p < .001, η_p² = .077); 2) individuals diagnosed with psychiatric disorders had higher scores (M = 1.759, SD = 1.666) on indices assessing psychiatric problems compared to others (p < .001, η_p² = .122); and individuals diagnosed with non-motor Frontotemporal Dementia had higher scores on indices of 3) behavioral activation (M = 2.424 , SD = 2.369, p < .001, η_p² = .141) and 4) behavioral suppression/disturbance (M = 2.652 , SD = 2.277, p < .001, η_p² = .188).

The four, previous-identified NPI-Q factors vary uniquely by etiology of dementia/cognitive impairment and may assist clinicians and researchers with more refined differential diagnosis and tailored treatment recommendations for different dementia syndromes. Future studies should explore these 4-factor model to understand its disease classification accuracy and associations with other neuropsychological outcomes to further validate the NPI-Q’s utility.