Agitation in Dutch institutionalized patients with dementia: factor analysis of the Dutch version of the Cohen-Mansfield Agitation Inventory

BACKGROUND/AIMS: To establish the construct validity of the Dutch version of the Cohen-Mansfield Agitation Inventory (CMAI-D) in institutionalized patients with dementia. METHODS: The CMAI-D was administered to a large sample of 1,437 patients with moderate to severe dementia, receiving nursing home or outreaching nursing home care. Exploratory factor analysis was used to examine the behavioral dimensions underlying CMAI-D observations. RESULTS: A restricted 3-factor solution showed 3 factors, i.e. physical aggression, physically nonaggressive behavior and verbally agitated behavior, with prevalences of 62, 67 and 62%, respectively. An unrestricted factor solution revealed 3 additional behavioral dimensions: hiding/hoarding, vocal agitation and a factor of miscellaneous items (i.e. repetitious mannerisms, spitting), which occurred in 30, 28 and 35% of the patients, respectively. CONCLUSION: The 3-factor solution of physical aggression, physically nonaggressive behavior and verbally agitated behavior corroborates earlier findings in other patient samples and therefore establishes the construct validity in institutionalized patients with severe dementia. The robustness of these findings across different care settings suggests that agitated behaviors have a common basis. In addition, unrestricted factor analysis showed 3 other important independent behavioral symptoms in dementia, but they are in fact too small to be used as a subscale. These findings might add to the taxonomy of agitation and aggression in dementia.