Correlates of financial toxicity in adult cancer patients and their informal caregivers

Background Financial toxicity is commonly reported by cancer patients, but few studies have assessed caregiver perceptions. We aimed to validate the modified Comprehensive Score for Financial Toxicity (COST) in cancer caregivers, identify factors associated with financial toxicity in both patients and caregivers, and assess the association of caregiver financial toxicity with patient and caregiver outcomes. Methods Using a convenience sampling method, 100 dyads of adult cancer patients and a primary caregiver visiting outpatient oncology clinics (Jan-Sep 2019) were recruited. We assessed the internal consistency and convergent and divergent validity of the modified COST. Multivariable analyses identified correlates of financial toxicity. Association of financial toxicity with care non-adherence, lifestyle-altering behaviors (e.g., home refinance/sale, retirement/saving account withdrawal), and quality of life (QOL) was investigated. Results Recruited patient vs. caregiver characteristics were as follows: mean age: 60.6 vs. 56.5; 34% vs. 46.4% female; 79% vs. 81.4% white. The caregiver COST measure demonstrated high internal consistency (Cronbach alpha = 0.91). In patients, older age (B, 0.3 [95% CI, 0.1-0.4]) and higher annual household income (B, 14.3 [95% CI, 9.3-19.4]) correlated with lower financial toxicity (P < 0.05). In caregivers, lower patient financial toxicity (B, 0.4 [95% CI, 0.2-0.6]) and cancer stages 1-3 (compared to stage 4) (B, 4.6 [95% CI, 0.4-8.8]) correlated with lower financial toxicity (P < 0.05). Increased caregiver financial toxicity correlated with higher care non-adherence in patients, increased lifestyle-altering behaviors, and lower QOL in patients and caregivers (P < 0.05). Conclusion The COST measure can also be used to assess caregiver financial toxicity. Caregivers' financial toxicity was associated with negative outcomes for both dyad members.