Nationwide trends in hospitalization, medical costs, and mortality for asthma after introduction of biologics: A cross-sectional study in the United States

BACKGROUND: Asthma is the most common inflammatory lung disease in the United States. Since 2015, biologic therapies have provided targeted treatment for patients with severe asthma. OBJECTIVE: To evaluate the trends for in-hospital outcomes of asthma before (2012-2014) and after (2016-2018) the introduction of biologic therapies for asthma. METHODS: We conducted a nationwide cross-sectional analysis of patients aged 2 years or older who were hospitalized for asthma between 2012 and 2018 using data from the Nationwide Readmissions Database. Outcomes included rates of asthma hospital admission and asthma-related 30-day readmission, hospital length of stay, hospital costs, and inpatient mortality. Generalized linear models assessed trends in rates of asthma admission and readmission, length of stay, costs, and mortality quarterly during 2012-2014 and 2016-2018. RESULTS: Among 691,537 asthma-related admissions, quarterly asthma admission rates significantly decreased (−0.90%, 95% CI = −1.46% to − 0.34%; P = 0.002) during 2016-2018, mainly among adults, but not during 2012-2014. Quarterly assessed readmission rates decreased by 2.40% (−2.85% to −1.96%; P < 0.0001) during 2012-2014 and by 2.12% (−2.74% to − 1.50%; P < 0.0001) during 2016-2018. Mean length of stay for asthma admissions decreased quarterly by 0.44% (−0.49% to − 0.38%; P < 0.0001) during 2012-2014 and by 0.27% (−0.34% to − 0.20%; P < 0.0001) during 2016-2018. Quarterly hospital costs for admissions were unchanged during 2012-2014 but increased by 0.28% (0.21% to 0.35%; P < 0.0001) during 2016-2018. There were no significant trends in inpatient mortality during 2012-2014 and 2016-2018. CONCLUSIONS: After the introduction of new biologics for severe asthma in 2015, asthma-related hospital admissions decreased significantly, whereas hospital costs increased. Asthma-related 30-day readmission rates and length of stay for asthma admissions continuously decreased, whereas inpatient mortality rates remained stable.