OBJECTIVES: Breast cancer is the most common cancer in women. The risk of breast cancer has increased slightly over time, while the death rate has declined steadily. This decline may be due to improvements in diagnosis, outpatient, or inpatient treatment. We investigated whether in-hospital death rates among patients admitted with a diagnosis of breast cancer declined in the US over the most recent period of data availability.

METHODS: Using the National Inpatient Sample 2012-2016, admissions with a diagnosis of breast cancer (single-level CCS – category 24) were identified. Descriptive measures including demographics, length of stay (LOS), discharge disposition, and total cost (adjusted for inflation using medical care component), stratified by year. Discharge-level weights were applied to represent national estimates, and domain analysis was used to account for the use of subpopulations.

RESULTS: In 2016, there were 751,185 admissions of patients with a diagnosis of breast cancer to US hospitals. Mean (95% confidence interval) age was 70.3 (70.1-70.5) years, 68.9% (68.3%-69.6%) had Medicare as their primary payer, and 73.3% (72.1%-74.4%) were White. Age slightly increased over the years studied, with the lowest mean of 69.8 (69.6-70.1) years in 2012 and 2013 (p=0.002). Mean LOS was 4.6 (4.6-4.7) days in 2012 and 2013 and 4.7 (4.7-4.8) days in 2016 (p<0.001). In-hospital death occurred in 2.8% (2.7%-2.9%) in 2012 and 2.9% (2.8%-3.0%) of admissions in 2016 (p=0.507). Mean cost of admission was $13,032 ($12,788-$13,276) in 2012 and $13,046 ($12,794-$13,298) in 2016 (p=0.940).

CONCLUSIONS: Among the three-quarters of a million US admissions per year with a diagnosis of breast cancer, the in-hospital death rate was stable from 2012-2016, despite a small increase in the age of admitted patients. Breast cancer mortality dropped 1.3% per year over a similar period, suggesting improved treatment and care in the outpatient setting may be responsible for the decrease.