Presentation and stability of noncognitive symptom patterns in patients with Alzheimer disease

The purpose of this study was to investigate noncognitive symptoms in Alzheimer disease to identify symptom patterns and to study stability of such patterns prospectively. Furthermore, variables were examined that could be associated with certain types of symptom patterns or could be predictors of change of these patterns. Forty-eight patients with the clinical diagnosis of probable Alzheimer disease were included in this study and were assessed weekly over a 3-week period. Noncognitive symptoms were rated according to the Behavioral Abnormalities in Alzheimer's Disease Rating Scale and the Dementia Mood Assessment Scale and to a set of items that specifically assess misidentifications. By means of principal component factor analysis different noncognitive symptom patterns were obtained, yielding a four-factor solution. They mapped onto rational domains with respect to clinical experience: depression, apathy, psychotic symptoms/aggression, and misidentifications/agitation. Demographic and clinical variables were not associated with the factor solutions and did not predict change of the factor values. The results demonstrate that in Alzheimer disease there are distinct noncognitive symptom patterns that hold at least short-term prospective stability. None of the examined clinical variables, such as age at entry, the status of the patients (outpatient or inpatient), or dementia severity, exerted substantial influence on the noncognitive symptom patterns. Further investigations should concentrate on the pathological and prognostic correlates of noncognitive symptom patterns in Alzheimer disease.