Medicaid’s impact: Findings from U-M research

Medicaid covers nearly 80 million people in the United States—one out of five people across the country, all with low incomes. Most are older adults, people with disabilities, children and pregnant women, but many others rely on it too.  

Over the last 60 years, and especially the last decade, Medicaid has grown into a comprehensive program that provides critical health care services to those who need them and helps support the broader health care system. It helps people get care from nursing homes, hospitals, doctor’s offices, clinics, home care services and mental health therapists for little or no cost.  

Medicaid pays for 4 out of every 10 births in the U.S., provides health coverage to half of all children and finances more than half of long-term nursing home stays.

Researchers at the University of Michigan Institute for Healthcare Policy and Innovation (IHPI) have studied Medicaid for years and published findings that can help inform Medicaid policy discussions. 

Here are 10 things that U-M research has shown about Medicaid:

1.   Medicaid expansion linked to lower death rates
A new review of studies by health economists Helen Levy, Ph.D. and Thomas Buchmueller, Ph.D., concluded that mortality declined with insurance coverage for all insurance types, but especially for people enrolled in Medicaid. 

This review includes the work of Sarah Miller, Ph.D., associate professor of business, and colleagues, who studied data from 2014-2017, the first three years after states gained access to more federal funding to expand Medicaid coverage. They found that deaths dropped by more than 9% among low-income people in the expansion states, compared with those in the states that did not expand Medicaid. The researchers estimate that if all states had expanded the program, more than 15,000 deaths would have been prevented in just three years. 

2.  High primary care access and preventive screening rates shown among Medicaid enrollees

An IHPI team led by John Ayanian, M.D., M.P.P., IHPI director and professor of internal medicine, has studied the people who receive Medicaid coverage through Michigan’s Medicaid expansion, called the Healthy Michigan Plan, for over a decade. As of May 2025, the program covered more than 700,000 people across all counties of the state.  

The team’s recent report showed that nearly all surveyed enrollees have a primary care provider (physician, nurse practitioner or physician assistant), 81% of them saw that provider in the last year, and long-term enrollees were very likely to get cancer screenings such as mammograms. Those who had regular preventive care were less likely to need emergency care. According to CDC data, this 81% primary care visit rate of Medicaid enrollees is comparable to privately insured adults (86%) and significantly higher than the 48% rate among uninsured adults

3. Medicaid coverage contributes to the financial stability of hospitals and clinics  
Ayanian and his colleagues have surveyed health care providers and analyzed data on Michigan hospitals to assess the impact of Medicaid expansion. 

They found that Michigan hospitals saw the amount of care for which they did not receive payment (also called uncompensated care) drop by half after Medicaid expansion, and that the percentage of hospitalized patients without insurance dropped by 69%. Primary care providers and safety-net clinics also reported improvements in financial stability and their ability to add services.

4. More use of high-value care seen in states that expanded Medicaid 

A study by Aaron Parzuchowski, M.D., M.P.H., M.Sc., clinical assistant professor of internal medicine, found that states that expanded Medicaid over the past decade saw a sharp increase in clinic visits that included “high-value” preventive care—especially for conditions affecting the heart, brain, and bones.  

High-value care means providing the right care for a person’s specific age, health conditions, and risk factors—care that is proven to work and avoids unnecessary costs or procedures. In expansion states, Medicaid enrollees were 19% more likely to be seen in clinics offering high-value care, while that same likelihood dropped by 24% in states that did not expand Medicaid in the same timeframe.  

5. Medicaid coverage helps low-income people stay in their jobs or seek jobs if they are able

The IHPI team evaluating Michigan’s Medicaid expansion program published a report based on surveys and interviews with Medicaid enrollees, along with analysis of statewide employment data from 2016-2018, to understand the impact of Medicaid on enrollees’ health and employment.  

The researchers found that half of the Medicaid enrollees already worked full or part-time. The rest were unable to work due to health issues or caregiving obligations, were studying or training for a career, or were out of work.

Analysis led by Renuka Tipirneni, M.D., M.Sc., associate professor of internal medicine, showed that the percentage of people enrolled in Michigan's Medicaid expansion program who had jobs or were enrolled in school jumped six percentage points in one year, a bigger jump than the state’s overall employment increase.

The team also found that 69% of enrollees who had jobs said they did better at work since enrolling in Medicaid, while 55% of those who were out of work said the coverage made them better able to look for a job. In interviews, enrollees shared that access to health care through Medicaid helped them manage physical and mental health conditions, allowing them to function better at work and pursue job opportunities.   

6. Medicaid plays a role in reducing enrollees' medical debt and financial challenges 

A study by Sarah Miller, Ph.D., showed that in the first year after enrolling in Michigan’s Medicaid expansion program, participants not only received coverage for their health needs, but many also experienced a boost in their finances.  

Michigan Medicaid expansion participants experienced sizable drops in their unpaid debts — medical debts and overdrawn credit cards in particular — and fewer bankruptcies and evictions, while their credit scores and approvals for car loans rose. They also experienced fewer debt problems and other financial issues than they had before enrolling. Those with chronic illnesses or who had a hospital stay or an emergency department visit after they enrolled saw the largest financial benefits. 

7.  Medicaid supports access to care among enrollees with behavioral health conditions, including addiction

U-M research finds that about half of the people covered by Michigan’s Medicaid expansion program have behavioral health conditions, including mental health disorders such as depression, or addiction to alcohol or drugs.

Tipirneni and colleagues found that people with these conditions got an especially big boost in many health and work-related measures after enrolling in Medicaid – bigger than the improvements seen in people who enrolled in the program but didn’t have a behavioral health condition.

A separate study by Kao-Ping Chua, M.D., Ph.D., associate professor of pediatrics, showed that when states “unwound” the special Medicaid enrollment that started during the COVID-19 pandemic, people who were taking medication that treats opioid addiction were more likely to have disruptions in their access to that medicine if they lived in one of the states that had the biggest drops in Medicaid enrollment. 

8. Medicaid helps low-income older adults afford health services
When someone is over age 65 and has an especially low income, they can qualify for both Medicare and Medicaid coverage. These “dually eligible” individuals often have a lot of medical needs, and research has found that Medicaid coverage has a positive impact on them.

For instance, a recent study by Tipirneni found that dually eligible individuals who lost their Medicaid coverage during the COVID-19 pandemic Medicaid “unwinding” process and later re-enrolled in Medicaid were much more likely to say they missed care due to cost, especially dental care and home health care.

Another U-M study showed that when the income of a dual-eligible person rose to just above Medicaid-eligible levels (and they no longer qualified for Medicaid coverage), they were then much less likely to see the doctor and less likely to be able to afford prescription medications -- especially if they were Black or Hispanic. 

9. Telehealth visits covered by Medicaid help people overcome barriers to care  
People with low incomes often face barriers to getting medical care in person, including transportation challenges and caregiving duties.

A recent study by Susan Dorr Goold, M.D., MHSA, M.A., professor of internal medicine, and IHPI scholar Terrence Liu, M.D., asked people with Medicaid coverage about their use of video and phone telehealth to get medical care. Nearly two-thirds of those who had a telehealth appointment in the past year said they received care that they could not or would not have received otherwise. 

10. Dental coverage through Medicaid linked to improved health and job prospects
While dental coverage under Medicaid varies from state to state, studies suggest it can have a major impact when it is included.

Edie Kieffer, Ph.D., M.P.H., professor emerita of social work, and colleagues at IHPI led a study of people who saw a dentist within two years of getting coverage through Michigan’s Medicaid expansion program. Almost 60% said their dental health had improved in that timeframe, and the majority of them said their improved oral health helped them do a better job at work or made them better able to look for a job. 

These are 10 examples, but there are many other U-M studies that have explored Medicaid's impact on people and their health, including topics ranging from pregnancy to mental health. 

See a list of stories about research on Medicaid by U-M faculty who are IHPI members: https://michmed.org/AQnM7

Learn more about IHPI’s evaluation of Michigan’s Medicaid expansion: https://ihpi.umich.edu/featured-work/healthy-michigan-plan-evaluation