The behavioral pathology in Alzheimer's Disease Scale (BEHAVE-AD): factor structure among community-dwelling Alzheimer's disease patients

OBJECTIVE: The aims of this study were to (a) determine the factor structure of the Behavioral Pathology in Alzheimer's Disease Scale (BEHAVE-AD), and (b) examine the associations of the observed factors to the level of cognitive impairment. DESIGN: Cross-sectional study of geriatric patients evaluated at an outpatient memory disorders clinic. SAMPLE: One hundred and fifty-one consecutive patients diagnosed with Alzheimer's disease (AD) according to NINCDS-ADRDA diagnostic criteria. RESULTS: Principal factors analysis with Varimax rotation resulted in a five-factor solution that accounted for 40.0% of the common variance. The factors included agitation/anxiety (agitation, anxiety of upcoming events; other anxiety), psychosis (delusions of theft, suspiciousness/paranoia; visual hallucinations), aggression (verbal aggressiveness; physical threats/violence; fear of being left alone; other delusions), depression (tearfulness; depressed mood) and activity disturbance (wandering; delusion one's house is not one's home). Several factors were associated with level of cognitive impairment as assessed by the Mini-Mental State Examination (MMSE). CONCLUSION: The results of this study suggest that the BEHAVE-AD measures a wide range of behavioral pathology that can be empirically represented by five independent symptom clusters among outpatient AD patients.