Caregivers' assessments of preference-based quality of life in Alzheimer's disease
published online 25 April 2008.
Abstract
Background
This study was designed to evaluate the feasibility, reliability, and validity of use of caregivers' ratings of two health preference measures as outcomes for cost-effectiveness analyses in persons with very mild to moderate Alzheimer's disease (AD).
Methods
Caregivers completed ratings of preference for AD patients' health by use of the EuroQol-5D system (EQ-5D) and the Health Utilities Index Mark 2 (HUI2). They also rated patients' cognition, mood, burden, AD-specific and generic health-related quality of life (QOL), and activities of daily living.
Results
Caregivers' HUI2 scores were reliable. Neither the caregiver ratings of the patients' health by use of the EQ-5D nor the HUI2 had a relationship with severity of cognitive impairment. Both the EQ-5D and the HUI2 had expected relationships with caregivers' assessments of patients' function, AD-specific QOL, and physical and mental health and selected subscales of the measures of AD-specific QOL and overall health. In addition, caregiver scores showed relationships with patient self-rated function, mood, and physical health but not AD-specific QOL. Caregiver burden was associated with caregivers' scores.
Conclusions
Caregiver-completed ratings of preference for patients' health made by use of the EQ-5D and the HUI2 have many of the characteristics of valid preference measures. However, the lack of association with patient Mini-Mental Status Exam scores and patient self-rated AD-specific QOL and the associations with caregiver subjective burden might present limitations to their use as proxy measures for cost-effectiveness analyses.
ABSTRACT