Measuring family HRQoL spillover effects using direct health utility assessment

Applications of cost-effectiveness analysis do not typically incorporate effects on caregiver quality of life despite increasing evidence that these effects are measurable.

Using a national sample of US adults, we conducted 2 cross-sectional surveys during December 2011 and January 2012. One version asked respondents to value their own experience as the family member of a person with a chronic illness (experienced sample), and the other version asked respondents to value hypothetical scenarios describing the experience of having a family member with a chronic illness (community sample). Conditions included Alzheimer's disease/dementia, arthritis, cancer, and depression. Using standard gamble questions, respondents were asked to value the spillover effects of a family member's illness. We used regression analysis to evaluate the disutility (loss in health-related quality of life) of having a family member with a chronic illness by condition and relationship type, controlling for the respondent's own conditions and sociodemographic characteristics.

For the experienced sample (n = 1389), regression analyses suggested that greater spillover was associated with certain conditions (arthritis, depression) compared with other conditions (Alzheimer's disease, cancer). For the community sample (n = 1205), regression analyses indicated that lower spillover was associated with condition (cancer) but not the type of relationship with the ill family member (parent, child, spouse).

The effects of illness extend beyond the individual patient to include effects on caregivers of patients, parents of ill children, spouses, and other close family and household members. Cost-effectiveness analyses should consider the inclusion of health-related quality of life spillover effects in addition to caregiving time costs incurred by family members of ill individuals.