Impact of functional alterations on quality of life in patients with Alzheimer's disease.
OBJECTIVES To assess the sensitivity of the 'Alzheimer's Disease Related Quality of Life' instrument (ADRQL) applied to Belgian people with dementia (n = 357), mild cognitive impairment (MCI) (n = 36), and controls (n = 72). We also determined the clinical parameters that influence the quality of life (QOL) of people with dementia. METHOD Each subject was evaluated with the ADRQL, the Mini Mental State Examination (MMSE), the cognitive scale of the Cambridge Examination for Mental Disorders of the Elderly (CAMCOG), the Katz's ADL classification (ADL), the Instrumental Activities of Daily Living (IADL), the Behavior Rating Scale for Dementia (CERAD/BRSD), and the Clinical Dementia Rating/Modified (CDR-M). RESULTS The ADRQL showed that QOL of the dementia group (65.77 +/- 17.04) was significantly inferior to that of the MCI (82.11 +/- 13.31) and control groups (79.75 +/- 15.82). There were no significant differences between the MCI and control groups. Within the dementia group, the five ADRQL subscale results were similar to those reported in other studies. Gender, age and place of residence had no significant influence on ADRQL scores. In contrast, ADRQL scores correlated significantly with MMSE, CAMCOG, IADL, ADL, CERAD/BRSD, and CDR-M. The MMSE and CERAD/BRSD were significant predictors of ADRQL variability. CONCLUSIONS QOL of people with dementia is inferior to that of people with MCI and controls. This demonstrates the ADRQL instrument is sufficiently sensitive for evaluating the QOL of people with dementia. Longitudinal studies are needed to specifically examine the rate of QOL evolution throughout the entire dementia process.