Association between frailty and clinical outcomes in older adults with early breast cancer: Results from the Hurria Older Patients (HOPE) study.

11040 Background: Older adults with early breast cancer are a heterogenous population with varying physiologic and functional age. Pretreatment frailty may help better characterize this heterogenous population compared to chronological age. We investigated the association between pretreatment frailty and clinical outcomes in older adults with early breast cancer treated with chemo. Methods: We leveraged a prospective cohort of 499 adults age ≥65 with stage I-III breast cancer undergoing treatment with neo/adjuvant chemo (R01AG037037). Pretreatment frailty status was determined using a Deficit Accumulation Index, which categorized patients as robust vs. prefrail/frail. Clinical outcomes included grade 3+ toxicity, dose reduction, treatment delay, early chemo discontinuation, hospitalization, and survival (overall, breast cancer related, and non-breast cancer related). We conducted a multivariable analysis evaluating the association between baseline frailty status (robust vs. prefrail/frail) and these outcomes, adjusting for age, race/ethnicity, stage, and regimen. Results: The median (range) age was 70 (65-86) years, 65% had stage II/III disease, and 38% received anthracycline. At baseline, 21% were prefrail/frail and 79% were robust. In total, 46% had a grade 3+ toxicity, 24% had a dose reduction, 26% had a treatment delay, 22% had early chemo discontinuation, and 23% were hospitalized. After multivariable analysis, prefrail/frail participants had greater odds of having grade 3+ toxicity (odds ratio [OR]=2.70, 95% CI, 1.66-4.40), dose reduction (OR=1.87, 95% CI 1.12-3.15), treatment delay (OR=1.85, 95% CI 1.10-3.13), and early chemo discontinuation (OR=1.76, 95% CI 1.05-2.95) compared to robust participants. Prefrail/frail participants had a higher likelihood of non-breast cancer related death (hazard ratio=2.56, 95% CI 1.08-6.05) compared to robust participants. There were no associations between frailty and hospitalizations, overall survival, and breast cancer related mortality. Conclusions: In this cohort of older adults with early breast cancer, participants who were prefrail/frail pretreatment had an increased risk of grade 3+ toxicity, dose reduction, treatment delay, early chemo discontinuation, and non-breast cancer related death. Pretreatment frailty assessments may improve risk stratification of older adults with early breast cancer and guide treatment decision-making. Clinical trial information: NCT01472094 . Clinical outcomes in older adults with early breast cancer, odds ratio (95% CI).* Frailty Status Grade 3+ Tox (n=229) Dose Reduction (n=120) Treatment Delay (n=132) Early Discontinuation (n=111) Hospitalization (n=115) Robust 1.00 1.00 1.00 1.00 1.00 Prefrail/Frail 2.70 (1.66-4.40) 1.87 (1.12-3.15) 1.85 (1.10-3.13) 1.76 (1.05-2.95) 1.61 (0.96-2.69) *Adjusted for age, race/ethnicity, stage, and regimen.