Changes in Insurance Coverage and Healthcare Use Among Immigrants and US-Born Adults Following the Affordable Care Act.

Objectives: Immigrants to the USA have disparate access to health insurance coverage and healthcare services. We evaluate the effects of gaining insurance following the January 2014 Affordable Care Act's (ACA) key provisions implementation on health services use among foreign- (FB) and US-born (USB) adults.

Methods: Longitudinal data from two panels (2013/2014 and 2014/2015) of the Medical Expenditure Panel Survey on FB and USB adults, ages 26-64 (unweighted n = 15,232), and difference-in-differences analysis using generalized estimating equations were used to estimate the effects of insurance gain. The primary outcomes were five measures of healthcare utilization including yearly routine care appointment, annual number of physician office visits, annual number of prescription medications filled or refilled, use of the emergency department (ED) during the year, and having an inpatient hospital stay during the year.

Results: Immigrants were more likely to gain health insurance between 2013 and 2015 relative to USB adults (6.3% vs. 4.4%) but remained much more likely to be continuously uninsured by 2015 (20.8% vs. 6.4%). Controlling for sociodemographic and health characteristics, FB and USB adults who gained insurance increased their use of health services, including routine care (absolute change Δ = 15.7%; p < 0.001 and Δ = 11.7%; p < 0.001), office-based doctor visits (Δ = 1.3; p < 0.001 and Δ = 0.6; p < 0.001), prescribed medications (Δ = 2.5; p < 0.001 and Δ = 1.6; p = 0.016), and inpatient hospitalizations (Δ = 3.6%; p = 0.017 and Δ = 3%; p < 0.001). ED use increased only among the FB (Δ = 4.8%; p < 0.001). Gaining insurance eliminated the differences in health services use for all considered outcomes among the FB relative to the continuously insured USB.

Conclusions: US immigrants had notable gains in health insurance after the ACA provisions took full effect, but major disparities in coverage persist. If insurance continues to expand among immigrants, then the gains may reduce longstanding disparities in health services use and enhance primary and preventive healthcare.