Contribution of psychosis and depression to behavioral disturbances in geropsychiatric inpatients with dementia.

BACKGROUND Specific behavioral disturbances in dementia may be associated with underlying disorders such as the presence of psychosis and depression. The objective of this study was to examine the association of depression and psychosis with behavioral disturbances in geropsychiatric inpatients with dementia. METHODS All admissions between October 1993 and May 1995 were reviewed to identify those patients admitted to the Houston Veterans Affairs Geropsychiatry Unit with a diagnosis of dementia; 208 patients were included in the study. Hierarchical regression models were constructed to explore the contribution of depressive and psychotic symptoms, and depression and psychosis diagnoses to Cohen-Mansfield Agitation Inventory (CMAI) scores. RESULTS Both depression and psychotic symptoms were significantly and positively correlated with behavioral disturbances. Psychotic symptoms were associated with aggressive behavioral symptoms, and depressive symptoms were associated with constant requests for help, complaining, and negativism. Dementia severity accounted for significant variance in CMAI scores and was positively associated with behavioral disturbance; though disorder symptoms accounted for more behavioral disturbance variance than did depressive symptoms. CONCLUSIONS Both depressive and psychotic symptoms were associated with overall behavioral disturbances in patients with dementia. Psychotic symptoms and depressive symptoms were associated with different types of behavioral disturbances. Our findings support the contention that underlying depression or psychosis may partially account for different behavioral disturbances and that not all behavioral disturbances should be globally labeled "agitation." Future studies should address symptom-specific treatment of behaviorally disturbed patients.