The Affordable Care Act and emergency department use by low acuity patients in a US hospital

Background: The Affordable Care Act (ACA) is one of the biggest healthcare reforms in US history. A key issue is the ACAs effect on low acuity, potentially primary care patients. This study evaluates the effect of the ACA on low acuity patients seen in the emergency department (ED). Methods: This is an age-period-cohort analysis for a community hospital ED in Michigan, from 2009 to 2015. Patients were stratified by age, year seen, emergency severity index (ESI) and insurance status. Data were compared between before and after ACA along with descriptive statistics, Chi-square and Student t-tests. The primary outcome was the change in ED usage by low acuity. Patients > 65 were used as a temporal control. Results: 305,350 ED visits were analyzed. ED visits with ESI 4/5 increased from 11.9% to 14.8%. Patients < 19 years increased from 25.5% to 34.3% (p = .0026). Ages 19-25 increased from 16.3% to 19.7% (p = 0.0515). Ages 26-64 increased from 11% to 14.9% (p = 0.0129). Ages > 65 increased from 5.1% to 6.5%. Patients < 65 showed a decreased uninsured rate from 12.30% to 6.28% (p < 0.0001). Comparatively, for age > 65: uninsured rate remained the same 0.46% to 0.49%. Conclusion: Low acuity ED visits increased with the ACA reform in conjunction with a more insured population.