Estimating informal caregiving time among older U.S. cancer survivors by health-related quality of life using the Health and Retirement Study.

Background: Informal care is a critical component of supportive care for cancer survivors. However, it is often overlooked in oncology economic evaluations because of the lack of systematically collected data on informal caregiving time. We aimed to provide nationally representative evidence on the magnitude of the informal caregiving burden among older cancer survivors in the United States and its variation by patients' health-related quality of life (HrQoL). Methods: Using Health and Retirement Study (HRS) data from 2010?2022, we included respondents aged ≥60 years with and without a history of cancer. The primary outcome was total monthly informal caregiving hours, defined as unpaid assistance with activities of daily living (ADLs) and instrumental activities of daily living (IADLs) received during the previous month and aggregated across caregivers. HrQoL was measured using the Health Utilities Index Mark 3 (HUI-3) and Visual Analog Scale (VAS). A two-part Gamma model examined the association between HrQoL and monthly informal caregiving hours, including a cancer status?HrQoL interaction term and adjusting for ADL/IADL limitations and sociodemographic characteristics. All analyses incorporated complex survey weights. Results: Among 30,372 person-wave observations, 5,386 (17.7%) had a history of cancer. Respondents with cancer received 61.5 hours of informal care per month, significantly more than the 45.5 hours received by those without cancer. Valued at $22/hour for home health aides, this corresponds to ?$1,350/month in informal care costs. Both HrQoL measures were significantly and inversely associated with informal caregiving. A 0.1-point increase in HUI-3 was associated with 6?8 fewer hours of informal care per month (P<0.001), and findings were consistent in models using VAS. The interaction between HrQoL and cancer status was not statistically significant (HUI-3: ?=?0.27, P=0.39; VAS: ?=?0.53, P=0.18), providing no evidence that the association between HrQoL and informal caregiving differed by cancer status. At the 90th percentile of HUI-3 (0.71), the predicted informal caregiving time was 12.9 hours/month for respondents with cancer and 9.2 hours/month for those without cancer. At the 10th percentile (HUI-3=0.38), predicted caregiving time increased to 80.4 and 69.1 hours/month, respectively. Conclusions: Older cancer survivors in the United States experience a substantial informal caregiving burden, which varies with HrQoL in a pattern similar to that observed among individuals without cancer. Higher HrQoL was consistently associated with lower informal caregiving needs, highlighting the potential value of supportive care, symptom management, psychosocial support, and disease-modifying therapies that maintain quality of life. Future oncology economic evaluations should incorporate informal care costs.