The Medicaid expansion under the Affordable Care Act promised to open doors to healthcare for millions, but could it also be opening the floodgates to antibiotic overuse? In the United States, over 200 million antibiotic prescriptions are filled annually, fueling a dangerous rise in antibiotic-resistant infections that claim more than 35,000 lives each year. My research explores an urgent question – has the well-intended expansion of healthcare access through the Medicaid expansion inadvertently encouraged greater inappropriate antibiotic use? Utilizing data from the U.S. Centers for Disease Control and the Kaiser Family Foundation, I explore the intricacies between increasing healthcare access and maintaining antibiotic stewardship in an era where every prescription truly counts.
Why focus on Medicaid expansion? The ACA’s Medicaid expansion, designed to increase health insurance coverage for low-income Americans, faced significant legal changes in 2012 when the Supreme Court ruled that states couldn’t be compelled to expand, thus transforming the program into a voluntary one. This provided a unique research opportunity to study access-related healthcare issues before and after the Act’s implementation through the use of a natural control – the states that have not expanded Medicaid.
My research hypothesizes that states that expanded Medicaid see higher rates of antibiotic use than those without. At the heart of my hypothesis is the theory of moral hazard, which suggests that more access to healthcare – like that provided by Medicaid expansion –leads to increased use of medical services because individuals are shielded from the full cost of that care. This increased access can be to both necessary and unnecessary care, leading to potential overuse of treatments such as unnecessary antibiotic prescriptions.
For my analysis, I use annual state-specific data on antibiotic prescriptions from the CDC, which tracks outpatient antibiotic use across the U.S. This dataset allows me to assess trends in antibiotic utilization, both before and after Medicaid expansion, to understand changes in antibiotic prescribing patterns. By analyzing this information, I am able to explore the implications of healthcare access on antibiotic use in various states.
I use a Difference-in-Differences (DID) analysis approach to compare changes in antibiotic use between states that expanded Medicaid and those that did not. In exploring the actual impact of Medicaid expansion on antibiotic prescription rates across the United States from 2011 to 2018, my research unveils some unexpected trends that challenge my initial assumptions. The data from 2011 to 2018 indicates that both expansion and non-expansion states saw a general decline in antibiotic prescriptions per 1,000 people, as is illustrated in Figure 1.
Figure 1: Mean Annual Antibiotic Prescriptions Per 1,000 People – Comparison between Non-Expansion and 2014-Expansion States (2011-2018):
Further, my DID analysis shows no statistically significant differences in the rate of decline between expansion and non-expansion states. These findings suggest that the Medicaid expansion did not, in fact, lead to higher antibiotic use in the states that implemented it compared to those that did not, contradicting my initial hypothesis that increased healthcare access would result in more antibiotic misuse.
In closing, through my analysis, it becomes clear that increased access to healthcare through the Medicaid expansion does not necessarily lead to greater antibiotic use as I originally hypothesized. The consistent decline in antibiotic prescriptions observed across all states, regardless of Medicaid expansion status, points to effective public health measures that may be contributing to the fight against antibiotic resistance. This suggests that other factors, potentially including nationwide initiatives on antibiotic stewardship, play a more critical role in guiding antibiotic use practices.
Despite these encouraging trends, the threat of antibiotic resistance remains significant. As we move forward as a society, there is still immense importance in continuing to develop multi-pronged strategies to address further antibiotic misuse and resistance in the nation as well as globally. There must be a concerted effort that encompasses further policy development and reform, education, and the promotion of best practices in antibiotic prescribing. By navigating these complexities, we can pave the way for a healthcare system that not only extends access to care but also upholds the highest standards of medical practice, ensuring the long-term efficacy of antibiotics and safeguarding public health against the looming threat of antibiotic resistance.
Kelly Anderson is a junior studying Healthcare Management and Policy at the O’Neill School of Public and Environmental Affairs. Kelly is passionate about all things health policy, and aims to address healthcare disparities and enhance access to quality care for underserved communities in her future career. At O’Neill, she serves as a Representative on the O’Neill Student Council, an Undergraduate Teaching Assistant for Statistics and Health Finance, and a Research Assistant for Professor John Graham.