OBJECTIVES: In health economic evaluations, all health effects should be considered, regardless of whether these effects occur in patients or others. The impacts of living with a non-healthy family member can be substantial. However, non-patient utilities are not commonly included in cost-utility analyses (CUA). This study aimed exploring impacts of living with a non-healthy family member for inclusion of non-patient utilities in CUA.

METHODS: An online survey was conducted in the UK among persons living with a non-healthy family member. The survey included background characteristics, impacts of living with the family member on respondent’s wellbeing, and health state valuations using time trade-off (TTO) and standard gamble (SG) exercises, by imagining hypothetical situations where respondents would undergo an organ, or bone marrow transplant, to restore their family members’ health. The transplant included risk of dying or a decreased life expectancy for the respondent. TTO and SG results were converted into utility scores for analysis.

RESULTS: The survey was completed by 500 respondents living with a non-healthy family member, of which most were reported to be in fair (41%) or poor (31%) health. Respondents (26-54%) perceived the impacts of their family member’s health as (somewhat) negative, particularly leisure time, overall happiness, social activities, and control over daily life. Respondents were willing to accept a risk of dying to restore their family member’s health between 61-66%. Besides, respondents were willing to trade-off between 45-49% of their remaining life expectancy to restore their family member’s health. For children, the largest risk was accepted (72%), and biggest trade-offs (67%) were made.

CONCLUSIONS: If the SG and TTO outcomes can be interpreted as utilities, excluding non-patient utilities in CUA results in substantially underestimating societal effects of ill-health and treatments. Discussion is needed about the influence and interpretation of altruistic preferences in the SG and TTO exercises.