Fragmentation of Care and Its Association With Survival and Costs for Patients With Breast Cancer in Colombia.

PURPOSE Breast cancer care requires a multimodal approach and a multidisciplinary team who must work together to obtain good clinical results. The fragmentation of care can affect the breast cancer care; however, it has not been measured in a low-resource setting. The aim of this study was to identify fragmentation of care, the geographic variation of this and its association with 4-year overall survival (OS), and costs of care for patients with breast cancer enrolled in Colombia's contributory health care system. MATERIALS AND METHODS A retrospective cohort study was conducted using administrative databases. Women with breast cancer who were treated from January 1, 2013, to December 31, 2015, were included. Fragmentation of care was the exposure, which was measured by the number of different health care provider institutions (HCPIs) that treated a patient during the first year after diagnosis. Crude mortality rates were estimated, survival functions were calculated using the nonparametric Kaplan-Meier approach, and adjusted hazard ratios (HRs) were estimated using multivariate Cox regression model to identify the association of fragmentation with 4-year OS. The association between fragmentation and costs of care was assessed using a multivariate linear regression model. RESULTS A total of 10,999 patients with breast cancer were identified, and 1,332 deaths were observed. The 4-year crude mortality rate was 31.97 (95% CI, 30.25 to 33.69) per 1,000 person-years for the whole cohort, and the highest rate was in the cohort defined for the fourth quartile of the fragmentation measurement (eight or more HCPIs), 40.94 (95% CI, 36.49 to 45.39). The adjusted HR for 4-year OS was 1.04 (95% CI, 1.01 to 1.07) for each HCPI additional. The cost of care is increased for each additional HCPIs (cost ratio, 1.25; 95% CI, 1.23 to 1.26). CONCLUSION Fragmentation of care decreases overall 4-year OS and increases the costs of care in women with breast cancer for Colombia.