Inequities in Breast Cancer Outcomes in Chile: An Analysis of Case Fatality and Survival Rates (2007-2018)

Introduction: The goal of this paper is to study inequities in breast cancer (BC) health care outcomes for Chilean women, including case fatality (FR) and survival rates (SR), stratified by type of health care provider and geographical area. A secondary goal is to estimate BC incidence (IR) and mortality (MR) rates by health care providers and region. Methods: We used two public anonymized databases provided by the Ministry of Health: the national death and hospital discharges datasets. For survival analysis, we used the Kaplan Meier product-limit estimator (KM) with a 95% ci and the Cox proportional hazards model (CM) with null-hypothesis significance testing of p>0.001. Results: We considered a cohort of 58,254 and 16,615 BC hospital discharges and deaths for the period 2007-2018. New cases and deaths due to BC increased by 43.6% and 33.6% respectively. Avg age-adjusted IR and MR were 44.0 and 10.5, respectively. Women affiliated to a private provider (ISAPRE) have an avg age adjusted IR of 60.6 compared to 38.8 for women affiliated with the public provider (FONASA). The national FR has remained constant over time, with a mean of 26.8. Women affiliated with ISAPRE had a considerably lower FR during the period under study, with an avg of 15.7 compared to 27.5 for women in FONASA. The avg 5-year SR were 0.81 and 0.90 for FONASA and ISAPRE. Women from the Metropolitan area have higher SRs than women from other regions. SRs obtained using the CM have a similar behavior to those obtained by the KM. Discussion: Despite the inclusion of BC in the GES plan in 2005 to provide greater, there are still significant differences in FR and SR for patients affiliated to ISAPRE compared to those in FONASA, a choice that is directly associated with socioeconomic level, and for patients in the Metropolitan and other regions. Further studies are required to determine the causes of these disparities.