While Medicaid is an important determinant of access to care overall, it does not appear that Medicaid alone has detectable effects on the management of several chronic physical health conditions, including diabetes and asthma.
November 01, 2021
Katherine Baicker, dean and Emmett Dedmon Professor at Harris

New research by Katherine Baicker, dean and Emmett Dedmon Professor at the University of Chicago Harris School of Public Policy, and coauthor Heidi L. Allen, associate professor of social work at Columbia University, uses the Oregon Health Insurance Experiment (OHIE) and data the authors collected through in-person interviews, physical exams, and more to estimate the effects of expanding Medicaid availability to a population of low-income adults on a wide range of outcomes, including healthcare utilization and health. The OHIE assesses the effects of Medicaid coverage by drawing on the 2008 lottery that Oregon used to allocate a limited number of spots in its Medicaid program.

The authors’ previous analyses have found that Medicaid increases healthcare use across settings, improves financial security, and reduces depression, but has no detectable effects on several physical health outcomes. For example, they found that while Medicaid did not significantly change blood sugar control, it did increase the likelihood of enrollees receiving a diagnosis of diabetes by a health professional and the likelihood that they had a medication to address their diabetes. However, it did not affect the prevalence, diagnosis, or treatment of hypertension or high cholesterol.

These results, coupled with the high burden of chronic disease in low-income populations, raised questions about how Medicaid does or does not affect the management of chronic physical health conditions. This new research – in a BFI working paper entitled “The Effect of Medicaid on Care and Outcomes for Chronic Conditions: Evidence from the Oregon Health Insurance Experiment” – explores the care and outcomes for such conditions, focusing on the more than 40 percent of the sample with chronic physical health conditions like high blood pressure, diabetes, high cholesterol, or asthma, both assessing new physical health outcomes and exploring in more detail the management of chronic conditions.

The authors examine biomarkers like pulse, markers of inflammation, and Body Mass Index across the entire study population; assess care and outcomes for asthma and diabetes; and gauge the effect of Medicaid on healthcare utilization for individuals with vs. without preexisting diagnoses of chronic condition. The authors find the following:

  • Medicaid does not significantly increase the likelihood of diabetic patients receiving recommended care such as eye exams and regular blood sugar monitoring, nor does it improve the management of patients with asthma.
  • There is no effect on measures of physical health including pulse, obesity, or blood markers of chronic inflammation.
  • Effects of Medicaid on health care utilization appear similar for those with and without pre-lottery diagnoses of chronic physical health conditions.

These findings lead the authors to conclude that while while Medicaid is an important determinant of access to care overall, Medicaid alone does not have significant effects on the management of several chronic physical health conditions, at least over the first two years, though further research is needed to assess the program’s effects in key vulnerable populations.