Health-related quality of life among elderly breast cancer patients treated with adjuvant endocrine therapy: a U.S Medicare population-based study

Objectives: The evidence regarding the impact of individual adjuvant endocrine therapies (AET) on health-related quality of life (HRQoL) is limited. We aimed to assess the association between the type of AET and HRQoL and to examine the relationship between HRQoL and one-year mortality among women with breast cancer in the USA. Methods: This retrospective cross-sectional study used the 2006–2017 Surveillance, Epidemiology, and End Results (SEER)-Medicare Health Outcomes Survey database to identify older women with early-stage hormone receptor-positive breast cancer. Multivariate linear regressions were used to assess the association between types of AET (anastrozole, letrozole, exemestane, and tamoxifen) and HRQoL scores (physical component summary (PCS) and mental component summary (MCS)). Multivariate logistic regressions were used to predict the impact of PCS and MCS on one-year mortality. Results: Out of 3537 older women with breast cancer, anastrozole was the most commonly prescribed (n = 1945, 55.0%). Regarding PCS, there was no significant difference between the four AET agents. Higher MCS scores, which indicate better HRQoL, were reported in patients treated with anastrozole (vs. letrozole [β = 1.26, p = 0.007] and exemestane [β = 2.62, p = 0.005) and tamoxifen (vs. letrozole [β = 1.49, p = 0.010] and exemestane [β = 2.85, p = 0.004]). Lower PCS and MCS scores were associated with higher one-year mortality, regardless of type of AET initiated, except for tamoxifen in MCS. Conclusion: Although there was no significant difference in physical HRQoL scores between AET agents, anastrozole and tamoxifen were associated with better mental HRQoL scores.