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Politics may have influenced prescribing of ineffective COVID-19 treatments, Harvard study suggests

A tablet of ivermectin arranged in Jakarta, Indonesia, on Thursday, Sept. 2, 2021.Dimas Ardian/Bloomberg via Getty Images

Hydroxychloroquine and ivermectin — two drugs that haven’t been found to work against COVID-19 — were more heavily prescribed in the latter part of 2020 in counties that voted more Republican in that year’s presidential election, according to a study from the Harvard T.H. Chan School of Public Health.

“This is the first evidence, to our knowledge, of such a political divide for a basic clinical decision like infection treatment or prevention,” Michael Barnett, assistant professor of health policy and management and lead author of the study, said in a statement from the school. “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.”


The findings on the prescribing of the two drugs, which are not approved COVID-19 treatments and are potentially dangerous, were published in a research letter Friday in JAMA Internal Medicine.

The researchers looked at data on outpatient visits for 18.6 million adults across the United States from January 2019 through December 2020. They compared prescription rates for hydroxychloroquine, an antimalarial drug, and ivermectin, an antiparasitic drug, with rates for two similar drugs, methotrexate sodium and albendazole, that have not been suggested as COVID-19 treatments.

The researchers found no major changes over the period in the prescribing of methotrexate sodium or albendazole. They also found no differences in prescribing of hydroxychloroquine and ivermectin by political leaning in 2019, before the pandemic hit.

In 2020, they found that prescribing of hydroxychloroquine was higher in less-Republican counties early in the year — before an emergency use authorization for the drug was revoked in June because of a determination it was unlikely to be effective. After June, more-Republican counties saw a higher level of hydroxychloroquine prescriptions.

Researchers also saw an increase in ivermectin prescribing in the second half of 2020, led by more-Republican counties. Ivermectin was never authorized for use against COVID-19. But the researchers noted that the increase, which spiked at the end of the year, aligned with various events, including the mid-November 2020 release of a now-retracted manuscript claiming the drug was effective, and a US Senate hearing in early December that included testimony from a doctor touting ivermectin. (The latest blow to ivermectin came in a separate study Friday in JAMA Internal Medicine that found “no evidence that ivermectin was efficacious in reducing the risk of severe disease.”)


Ivermectin and hydroxychloroquine have been promoted by anti-vaccine groups as treatments for COVID-19 since early in the pandemic. Former Republican president Donald Trump also promoted hydroxychloroquine as a treatment early in the pandemic, even saying he was taking it.

The researchers noted that their observational study could not determine the “causality of the association between county-level political voting patterns and prescribing of 2 ineffective COVID-19 treatments.”

They also said they were unable to determine what the role of the doctor or patient was in the prescribing patterns.

“These limitations notwithstanding, our findings are consistent with the hypothesis that US prescribing of hydroxychloroquine and ivermectin during the COVID-19 pandemic may have been influenced by political affiliation. Because political affiliation should not be a factor in clinical treatment decisions, our findings raise concerns for public trust in a nonpartisan health care system,” the study said.

Dr. Mugur V. Geana, a University of Kansas professor who has studied the role of political ideology in health behaviors during the pandemic, said the study raises “interesting questions that require additional scrutiny.”


He said in an e-mail that ideology affecting people’s health decisions is “a reality of the times we live in. We have a society that is polarized along many dimensions: economic, racial, social, ideological, to name a few. We also have a pandemic and an overload of health information that most people cannot efficiently process. When that happens, we tend to defer decisions or adoption of specific behaviors to the attitude or behaviors of the group that we identify with.”

Martin Finucane can be reached at martin.finucane@globe.com.