Northwestern University

Effects of Insurance Expansion under the Affordable Care Act on Medium and Long-term Diabetes Diagnosis, Severity, Health Outcomes and Costs


The ACA substantially reduced the number of uninsured persons, especially in Medicaid expansion states, and for poorer persons, who were more likely to be uninsured prior to the ACA. Understanding the health and economic effects of Medicaid expansion has profound policy implications, for diabetes care, for other chronic conditions where outcomes can be affected by improved access to care and medical management, and for potentially reducing disparities in health outcomes. This study will examine the medium- and long-term effects of gaining insurance under the ACA, both through Medicaid expansion and under the individual insurance exchanges, on diabetes diagnosis, treatment, severity, health outcomes, and costs.


Effects of Medicaid Coverage and State-Level Delivery Approaches on Healthcare Quality, Outcomes, and Costs for Adults with Diabetes


Under federal policy, Medicaid programs must offer minimum essential benefits but may request waivers to implement additional eligibility requirements or changes to these benefits.  Most states, including those that expanded Medicaid under the Patient Protection and Affordable Care Act (ACA) administer Medicaid programs in partnership with managed care organizations.  States deploy limited public resources attempting to balance access, quality, outcomes and cost in their Medicaid programs, particularly for patients with chronic conditions such as type 2 diabetes and for new, expensive medications such as sodium-glucose co-transporter-2 (SGLT2) inhibitors.  This study will conduct two complementary analyses: 1) examine the effects of Medicaid expansion on diagnoses of type 2 diabetes, severity of type 2 diabetes, health outcomes and costs for over 8 million patients in Illinois, Indiana and Wisconsin and 2) among a national cohort of UHC beneficiaries, compare the effects of state-level Medicaid policies that lower barriers for the initiation and use of SGLT-2 inhibitors on medication starts, acute diabetes complications, and costs including drug-specific expenditures.

Dr. Ronald Ackermann
Dr. Abel Ko
Dr. Bernard Black

We are ecstatic to collaborate with this national network to implement innovative solutions for how to apply natural experimental study designs in creative new ways with real world administrative and clinical data sources, in order to inform health policies and practices that lead to health and health equity for people with diabetes.

-Dr. Ronald Ackermann, MD, MPH, Dr. Abel Ko, MD, MS, FACMI, Dr. Bernard Black, JD, Co-Principal Investigators of Northwestern Team