PURPOSE Frailty is assessed when making treatment decisions among older women with breast cancer (BC), which in turn impacts survival. We evaluated associations between frailty and risks of BC-specific and all-cause mortality in older women.
METHODS We conducted a retrospective cohort study of Medicare beneficiaries ages ≥65 years with stage I-III BC using the Surveillance, Epidemiology and End Results Medicare Health Outcome Survey Data Resource. Frailty was measured using the deficit-accumulation frailty index, categorized as robust, pre-frail or frail, at baseline and during follow-up. Fine and Gray competing risk and Cox proportional hazards models were used to estimate sub-distribution hazard ratios (SHR) and hazard ratios (HR) with 95% confidence intervals (CI) for BC-specific and all-cause mortality, respectively.
RESULTS Among 2,411 women with a median age of 75 years at BC diagnosis, 50% were categorized as robust, 29% were pre-frail and 21% were frail. Compared to robust women, fewer frail women received breast-conserving surgery (52% vs. 63%) and radiation (44% vs. 52%). In multivariable analyses, frail women had higher risks of all-cause mortality compared to robust women (HR 2.16, 95% CI 1.80-2.60).
CONCLUSION Frail women in our study had a higher cumulative hazard of BC-specific death, but this observed higher risk was not significant after accounting for differences in treatment and competing risks of other-cause death. Measuring frailty may help determine overall life expectancy but not BC-specific death.
Table. Risk of Breast Cancer-Specific and All-cause Mortality, using time-varying DAFI measureEventsCrude SHRRobust 95%CIP-valueMinimally Adjusted SHRaRobust 95%CIP-valueFully Adjusted SHRbRobust 95%CIP-valueBreast Cancer-Specific MortalityDAFI CategoriesRobust891.001.001.00Pre-frail691.250.91 – 1.700.161.150.84 – 1.590.381.060.77 – 1.480.72Frail621.531.11 – 2.110.011.371.00 – 1.900.051.190.85 – 1.660.31All-Cause MortalityDAFI CategoriesRobust2721.001.001.00Pre-frail2241.551.30 – 1.84<0.00011.411.19 – 1.68<0.00011.371.15 – 1.63<0.0001Frail2362.32.12 – 3.02<0.00012.331.96 – 2.78<0.00012.161.80 – 2.60<0.0001DAFI = deficit-accumulation frailty index; HR = hazard ratio; SHR = subdistribution hazard ratios; CI = confidence intervalsa adjusted for age categories and breast cancer staging b adjusted for age categories, breast cancer staging, surgery type, radiation, Estrogen/Progestin Receptor, race/ethnicity, marital status, and education
Citation Format: Connie H Yan, Chandler Coleman, Nadia A Nabulsi, Brian Chiu, Naomi Y Ko, Kent Hoskins, Gregory S Calip. Associations between frailty and cancer-specific mortality among older women with breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-13.
