Preventable Hospitalization Trends Before and After the Affordable Care Act.

Introduction: The Patient Protection and Affordable Care Act aimed to increase the number of individuals with health insurance, which may lead to adequate primary care management and reduced rates of preventable hospitalizations. To investigate the rates of preventable hospitalization after the passing of the Affordable Care Act in 2010 and Medicaid expansion in 2014 across 26 states, a population-based study was conducted using the Healthcare Cost and Utilization Project National Inpatient Sample database from 2005-2017.

Methods: A logistic regression and trend analysis was performed to assess the changes in preventable hospitalization rates over time and the impact of policy changes on the rate of preventable hospitalization. Individuals were included if they were aged between 18 and 64 years and had a preventable quality indicator International Classification of Diseases, Ninth or Tenth Revision code as determined by the Agency for Healthcare Research and Quality.

Results: More than 45 million preventable-hospitalization admissions were reported between 2005 and 2017. There was a significant decrease in preventable hospitalization rates after the passing of the Affordable Care Act from 12.0% to 10.8% (<0.01) and from 11.5% to 10.6% (<0.01) after Medicaid expansion. Bacterial pneumonia declined from 1.5% to 0.6% (<0.01), along with chronic obstructive pulmonary disease and asthma in older adults from 1.9% to 1.7% (=0.01) after the expansion.

Conclusions: States that have not implemented Medicaid expansion should make it a priority because it may lead to a reduction in preventable hospitalization rates. Furthermore, preventable hospitalization rates may be considered a quality measure to examine the accessibility and effectiveness of primary care intervention.