Differences Between Self- and Proxy-Assessment of Health-Related Quality of Life in Patients with Mild Cognitive Impairment and Alzheimer's Disease

Abstract

The self-assessment of health-related quality of life (HrQoL) in patients with Alzheimer's disease (AD) and mild cognitive impairment is commonly higher than the proxy-assessment by caregivers. This study aims at evaluating sociodemographic and clinical factors to explain this difference. HrQoL of 241 community-dwelling patients was analysed using the dementia-specific Quality of Life-Alzheimer's Disease questionnaire (QoL-AD). Behavioural and psychological symptoms and functional capacity were evaluated using the Geriatric Depression Scale (GDS), the Neuropsychiatric Inventory (NPI) and the Alzheimer's Disease Cooperative Study-Activities of Daily Living scale (ADCS-ADL). The self-assessment of patients' HrQoL was significantly higher than the caregiver-ratings (mean difference: 7.4 ± 5.6, p < 0.001). Considerable influencing factors were the extent of depressive symptoms (GDS), the degree of impairment in functional performance (ADCS-ADL) and the relationship between patients and caregivers. Independent variables explained 23 % of the variance in the difference between self- and proxy-assessment of HrQoL. Future studies should include further influencing factors such as caregivers' mental health.