ACA Medicaid Expansion Linked to Increase in Diabetes Diagnoses

Revised ADA Standards Allow Personalized Approach to Diabetes Treatment
Revised ADA Standards Allow Personalized Approach to Diabetes Treatment
States that expanded Medicaid under the Affordable Care Act have higher rates of newly-diagnosed diabetes.

In states that expanded Medicaid under the Affordable Care Act (ACA), significantly more adults have been newly diagnosed with diabetes than in states that did not expand Medicaid, according to a study published in Diabetes Care.

Effective Jan. 1, 2014, the ACA expanded Medicaid eligibility to include non-elderly adults with incomes at or below 138% of the federal poverty level (approximately $16,105 for individuals). Offering this expanded coverage was optional for states: 26 (plus the District of Columbia) chose to expand coverage and 24 opted out.

This division between states provided a unique opportunity for the researchers to investigate the effects of Medicaid expansion on health metrics. The researchers chose to focus on diabetes due to its widespread occurrence, large at-risk population, and improved outcomes upon early diagnosis.

The study included patients aged 19 to 64 years from the Quest Diagnostics database. The researchers defined newly-diagnosed diabetes as an ICD-9 diagnosis code of 150.x or HbA1c levels greater than 6.4% (46 mmol/mol) within the first 6 months of a calendar year.

First, the researchers looked at a control period (the first half of 2013). In this control period, 26,237 total Medicaid patients were newly diagnosed with diabetes: 14,625 in expansion states and 11,612 in non-expansion states.

In the study period (the first half of 2014), 29,673 people enrolled in Medicaid were newly diagnosed with diabetes. In the states that expanded Medicaid, there was a 23% increase in the number of adults newly diagnosed with type 1 or type 2 diabetes (n=18,020). In states that did not expand coverage, that increase was only 0.4% (n=11,653).

The researchers hypothesize that this increase is due to better access to health care for those enrolled in Medicaid, allowing diabetes to be diagnosed at an earlier stage. Because these patients were diagnosed earlier, the researchers believe they will be able to receive better treatment, reducing the possibility of long-term complications.

“By increasing access to health care, Medicaid expansion allows people to know their status and receive life-preserving treatments to help improve their quality of life and to prevent serious and costly complications,” Robert E. Ratner, MD, FACP, FACE, the Chief Scientific Medical Officer for the American Diabetes Association, said in a press release. 

“We hope that those states that have not yet expanded their Medicaid coverage will see the potential advantages of improved health and productivity for their citizens and initiate their own Medicaid expansion.”

Based on the trends observed in this study, the researchers believe that Medicaid expansion will likely affect the diagnosis of conditions including hypertension, high cholesterol, and chronic kidney disease.

In an accompanying commentary, Diabetes Care Editor-in-Chief William T. Cefalu, MD, and William H. Herman, MD, MPH, professor of internal medicine and epidemiology at the University of Michigan, discussed study’s findings in light of the economy.

“The current trajectory for economic costs for the U.S. is not sustainable … perhaps the time is right to reevaluate our health policies,” they wrote. 

“The data demonstrate the benefits of Medicaid expansion, yet nearly half our states have chosen not to expand this benefit to their citizens. The real-world benefits and costs of Medicaid expansion merit additional research and civil debate. And perhaps most important, their results should be used to guide health policy to address the growing burden of chronic diseases,” Drs. Cefalu and Herman wrote.


  1. Kaufman HW et al. Diabetes Care. 2015;doi:10.2337/dc14-2334.
  2. Herman WH, Cefalu WT. Diabetes Care. 2015;doi:10.2337/dc15-0348.