Relationship between cognitive status and behavioral symptoms in Alzheimer's disease and mixed dementia.

OBJECTIVE

To investigate the relationship between cognitive and behavioral impairments in Alzheimer's disease (AD) and to examine whether the addition of cerebrovascular disease modifies that relationship.

DESIGN

Correlational analysis.

SETTING

An outpatient dementia clinic.

PATIENTS

An autopsy-confirmed series of 28 patients with AD and 16 patients with mixed Alzheimer and vascular dementia (MIX).

MEASUREMENTS

Neuropsychological and behavioral tests during life: Mini-Mental State (MMS), Blessed Dementia Scale (BDS), Haycox Dementia Behavior Scale (HDBS), and two non-cognitive functional scales derived from the BDS and HDBS.

RESULTS

In the AD group, MMS scores correlated significantly with scores on the BDS, HDBS, and two non-cognitive functional scales. In the MIX group, however, no significant relationship was observed between MMS scores and scores on any of the behavioral measures.

CONCLUSIONS

These observations suggest that in AD, cognitive and behavioral impairments progress simultaneously. However, with the addition of a vascular component to the dementing process, cognitive and behavioral impairments may progress more independently.