Relationship between behavioral problems and cognitive status in Alzheimer type and mixed Alzheimer and vascular dementia

Abstract

To investigate the relationship between troublesome behavior and cognitive status in Alzheimer type dementia (DAT), and to know whether the addition of cerebrovascular ischemia modifies that relationship, we studied behavioral and cognitive data from a clinical series of 57 DAT patients (mean age: 83.4 yrs) and 31 patients with mixed Alzheimer and vascular dementia (MIX) (mean age: 83.4 yrs). All subjects were ambulatory and were recruited from among patients having been admitted to our affiliated nursing home. None of them had any serious systemic diseases. The Dementia Behavior Disturbance scale (DBD), originally developed by Baumgarten et al, and the Mini-Mental State (MMS) were used for the evaluation of behavioral problems and cognitive status, respectively. In the DAT group, a significant correlation was recognized between DBD and MMS scores. In the MIX group, however, DBD scores did not correlate with MMS scores. Among patients having MMS scores greater or equal to 20, those with MIX had higher DBD scores (mean 19.3) than those with DAT (mean 13.7), although MMS scores in these two subgroups were comparable. These findings suggest that in DAT, behavioral problems increase in conjunction with cognitive impairments. However, with the addition of cerebrovascular ischemia to Alzheimer pathology, behavioral impairments may progress independently of cognitive decline, with more frequent presentation of troublesome behaviors in the early stage of dementia.