Abstract 979: Caregiver experiences and prostate cancer survivor quality-of-life in the Detroit Research on Cancer Survivors study

Abstract Introduction: Cancer survivorship is influenced by informal (unpaid) caregiving received by survivors. However, informal caregivers often experience caregiving-related burden, or strain from providing care, which may, in turn, impact health-related quality-of-life (HRQoL) among cancer survivors. We investigated associations of caregiver burden and involvement intensity with HRQoL of prostate cancer survivors receiving care. Methods: We included 323 prostate cancer survivor-caregiver dyads who participated in the Detroit Research on Cancer Survivors study, a population-based cohort of Black cancer survivors. Informal caregivers were invited to report on their experiences, including caregiving burden (via Zarit Burden Interview [ZBI]) and involvement intensity (via Level of Care Index); these were measured at caregiver enrollment. Survivors completed enrollment and follow-up (approximately annually) surveys, including measuring HRQoL using the Functional Assessment of Cancer Therapy tool; we measured HRQoL for up to 6 years. We examined overall QoL (range 0-108), subscales of functional, social, physical (each 0-28), and emotional (0-24) wellbeing, and prostate cancer-specific QoL (0-48); higher scores reflect better HRQoL. We used linear mixed effects models including exposure-time interactions to evaluate differences in survivor HRQoL scores at enrollment and over time by each exposure, adjusting for survivor and caregiver sociodemographics, survivor health, and cancer and dyad relationship characteristics. Results: Survivor median age at diagnosis was 62 years. Most informal caregivers were the survivor’s partner (68%) and were women (94%). Most caregivers reported low burden (ZBI < 21; 82%), and most were highly involved (60%). At enrollment, low vs. moderate or higher caregiver burden was associated with better overall QoL (mean difference 8.7, 95% Confidence Interval [CI] 4.1, 13.2), prostate cancer-specific QoL (3.1, 95% CI 0.8, 5.4), functional wellbeing (3.1, 95% CI 1.4, 4.8), and slightly, emotional and physical wellbeing. Having a low vs. high involved caregiver was associated with better overall QoL (7.3, 95% CI 2.8, 11.7), prostate cancer-specific QoL (4.0, 95% CI 1.7, 6.3), functional wellbeing (3.2, 95% CI 1.5, 4.9) and slightly, physical wellbeing at enrollment. On average, the additional change in physical and prostate cancer-specific QoL scores per year comparing survivors with caregivers who have low vs. moderate or higher burden was -0.5 (95% CI -0.8, -0.1) and -1.3 (95% CI -2.4, -0.3) lower, respectively. Conclusion: While informal caregivers’ experiences immediately influenced survivor HRQoL, we also observed that the relationship of caregiver burden with physical forms of wellbeing differed over time. Supporting informal caregivers can impact the care recipients, potentially having long-term influence for cancer survivors. Citation Format: Colleen B. McGrath, Jamaica R. Robinson, Konrad H. Stopsack, Julie J. Ruterbusch, Michelle O. Sodipo, Kathryn L. Penney, Briana J. Stephenson, Laura D. Kubzansky, Lorelei A. Mucci, Jennifer Beebe-Dimmer. Caregiver experiences and prostate cancer survivor quality-of-life in the Detroit Research on Cancer Survivors study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 979.