Behavioral problems in dementia: a factor analysis of the neuropsychiatric inventory.

The aim of this study was to detect behavioral subsyndromes of the 12-item Neuropsychiatric Inventory (NPI). Cross-sectional data of 199 patients with dementia living in the community were collected. Principal component analysis (with Varimax rotation) was used for factor analysis. Results showed the presence of three behavioral subsyndromes: mood/apathy, psychosis, and hyperactivity. Anxiety was regarded as a separate symptom. The subsyndrome mood/apathy was the most common, occurring in almost 80% of the patients, versus psychosis and hyperactivity, which occurred in 37 and 60% of the patients, respectively.