Executive dysfunction and apathy predict functional impairment in Alzheimer disease.

OBJECTIVE

The purpose of this study was to examine the extent to which executive cognitive dysfunction and frontally-mediated behavioral disturbances are associated with functional impairment in patients with mild-to-moderate Alzheimer disease (AD).

METHODS

Patients with AD (N=45) completed the Mattis Dementia Rating Scale, and patients' caregivers completed the Frontal Systems Behavioral Inventory and a modified form of the Lawton and Brody Activities of Daily Living (ADLs) Questionnaire.

RESULTS

Multiple-regression analyses revealed that executive cognitive dysfunction and apathy scores accounted for 44% of the variance in instrumental activities of daily living; executive cognitive dysfunction alone explained 17% of the variance in instrumental ADLs, and apathy scores explained an additional 27%. Executive dysfunction and frontal-behavioral impairment explained 28% of the variance in basic ADLs (BADLs), and, after accounting for executive dysfunction, apathy was the only symptom found to explain additional unique variance in BADLs.

CONCLUSION

These findings suggest that specific cognitive and behavioral symptoms are associated with functional impairment in patients with AD.