Political affiliation may have swayed prescribing of ineffective COVID drugs

For immediate release: February 18, 2022

Boston, MA – Two treatments that have been shown to be ineffective against COVID-19—hydroxychloroquine and ivermectin—were more heavily prescribed in the latter part of 2020 in U.S. counties with a higher Republican vote share in the 2020 presidential election, according to a new research letter co-authored by researchers from Harvard T.H. Chan School of Public Health.

The study was published online February 18, 2022 in JAMA Internal Medicine.

“We’d all like to think of the health care system as basically non-partisan, but the COVID-19 pandemic may have started to chip away at this assumption,” said Michael Barnett, assistant professor of health policy and management and lead author of the study.

The study compared prescription rates for hydroxychloroquine and ivermectin with rates for two control medications, methotrexate sodium and albendazole, which are similar drugs but have not been proposed as COVID-19 treatments. Researchers looked at deidentified medical claims data from January 2019 through December 2020 from roughly 18.5 million adults across the U.S., as well as U.S. Census data and 2020 U.S. presidential election results.

Overall, hydroxychloroquine prescribing volume from June through December 2020 was roughly double what it had been the previous year, while ivermectin prescribing volume was seven-fold higher in December 2020 than it had been the previous year. In 2019, prescribing of hydroxychloroquine and ivermectin did not differ according to county Republican vote share. But that changed in 2020.

After June 2020—coinciding with when the U.S. Food and Drug Administration revoked emergency use authorization for hydroxychloroquine—prescribing volume for the drug was significantly higher in counties with the highest Republican vote share as compared to counties with the lowest vote share.

As for ivermectin, prescribing volume was significantly higher in the highest versus lowest Republican vote share counties in December 2020—964% higher than 2019 overall prescribing volume. The spike aligned with several key events, such as the mid-November 2020 release of a now-retracted manuscript claiming that the drug was highly effective against COVID-19, and a widely publicized U.S. Senate hearing in early December that included testimony from a doctor promoting ivermectin as a COVID-19 treatment.

Neither of the control drugs had differences in overall prescribing volume or in prescribing by county Republican vote share.

The findings suggest that the prescribing of hydroxychloroquine and ivermectin could have been influenced by physician or patient political affiliation, the authors concluded. “This is the first evidence, to our knowledge, of such a political divide for a basic clinical decision like infection treatment or prevention,” said Barnett.

“Association of County-Level Prescriptions for Hydroxychloroquine and Ivermectin With County-Level Political Voting Patterns in the 2020 US Presidential Election,” Michael L. Barnett, Marema Gaye, Anupam B. Jena, Ateev Mehrotra, JAMA Internal Medicine, February 19, 2022, doi: 10.1001/jamainternmed.2002.0200

photo: iStock

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Nicole Rura

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Harvard T.H. Chan School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere. As a community of leading scientists, educators, and students, we work together to take innovative ideas from the laboratory to people’s lives—not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices. Each year, more than 400 faculty members at Harvard Chan School teach 1,000-plus full-time students from around the world and train thousands more through online and executive education courses. Founded in 1913 as the Harvard-MIT School of Health Officers, the School is recognized as America’s oldest professional training program in public health.