Cognitive Fluctuations and Cognitive Test Performance Among Institutionalized Persons With Dementia.

OBJECTIVE: To examine the nature and frequency of cognitive fluctuations (CFs) among institutionalized persons with dementia.

METHOD: A clinical interview and a medical chart review were conducted, and 55 patients were assigned a specific dementia diagnosis. The Severe Impairment Battery (SIB) was administered to assess cognitive function, and the Dementia Cognitive Fluctuation Scale (DCFS) was administered to each patient's primary nurse to determine the presence and severity of CFs.

RESULTS: A simple linear regression model was conducted with DCFS as the predictor variable and SIB total score as the dependent variable. The overall model was significant, suggesting that score on the DCFS significantly predicted SIB total score. Additionally, greater severity of CFs predicted poorer performance in the areas of orientation, language, and praxis.

CONCLUSIONS: Results suggest that CFs exert a clinically significant influence over patients' cognitive abilities and should be considered as a source of excess disability.