The association between caregiver burden and caregiver health-related quality of life in Alzheimer disease

The burden experienced by family caregivers of individuals with Alzheimer disease (AD) affects the caregivers' overall health-related quality of life (HRQOL). Assessing the influence on HRQOL is an integral part of determining the efficacy and economic attractiveness of interventions for AD. Generic preference-weighted instruments such as the Health Utilities Index Mark 2 (HUI2) are recommended for measuring HRQOL for cost-effectiveness studies. However, these instruments focus on physical attributes and have not been tested in an AD caregiver population. We administered the HUI2 to a population of 679 caregivers to people with AD at 13 community and institutional sites in the United States. We also administered the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), a caregiver time questionnaire, and a caregiver burden instrument. The mean global HUI2 utility score for caregivers was 0.87 and varied little by the affected person's setting of care and AD stage (range, 0.86-0.89; p > 0.2). The caregiver burden scales all varied by the affected person's setting of care, and some also varied by disease severity. The mental health component summary score of the SF-36 for caregivers varied across both disease stage and setting. Caregiver time increased for caregivers of AD-affected persons with more severe cognitive impairment. Generic preference-weighted instruments may not adequately capture differences in the burden of caregivers of those with AD. The development of condition-specific preference-weighted instruments may provide the means to better estimate HRQOL in AD caregivers.