Out-of-pocket spending fell an average of 28% for people enrolled in Medicaid, the state and federal health insurance program for low-income people, during the first four years of the Affordable Care Act, popularly known as Obamacare. The likelihood that Medicaid recipients would experience a catastrophic medical expense fell by 4.7% during the four-year study period, the researchers found.


Medicaid is a state and federal health insurance program for low-income people. Under the Affordable Care Act, state Medicaid programs were expanded in 36 states and the District of Columbia to make health insurance available to a larger group of low-income people.


The study used data from the 2010-2017 Medical Expenditure Panel Survey of a nationally representative sample of nearly 38,000 adults under age 65 with family incomes below 138% of the federal poverty level. The researchers compared 26 states that had implemented their Medicaid expansion or similar programs on Jan. 1, 2014, and 18 states that did not. The researchers note some limitations to their findings, including that some differences between expansion and non-expansion states may not have been captured through their approach.


The Medicaid expansions have improved health-related financial risk protection for low-income adults, which was one of the primary goals of the Affordable Care Act.


Authors are Dr. Yusuke Tsugawa and Gerald Kominski of UCLA, Dr. Hiroshi Gotanda of Cedars-Sinai Medical Center in Los Angeles, and Dr. Ashish Jha of Harvard University and Brigham and Women’s Hospital in Boston.


The study is published in the peer-reviewed journal The BMJ.