New study reveals risks of fluoroquinolone use in all adults

Fluoroquinolones should be used with caution in all adults, not just in high-risk individuals, suggests a new study published in the January 2020 issue of JAMA Surgery. The study, conducted by Newton and colleagues, found an increased incidence of aortic aneurysm in U.S. adults with no known previous aortic aneurysm or dissection who were taking fluoroquinolones—a powerful class of antibiotics commonly prescribed in the United States.

The researchers sought to determine whether recent international data showing an increased risk of aortic aneurysm and dissection with fluoroquinolone use would hold true for the U.S. population—and specifically, to learn “who was truly at risk.” Their research was a response to recent international data showing an increased risk of aortic aneurysm and dissection with fluoroquinolone use, which prompted FDA to issue warnings limiting their use for high-risk patients.

From March 2019 to May 2020, Newton and colleagues conducted a retrospective analysis of U.S. health insurance claims data from 2005 to 2017 among individuals aged 18 to 64 years with no known previous aortic aneurysm or dissection, no recent antibiotic exposure, and no recent hospitalization. They estimated the association between fluoroquinolone fill and 90-day aneurysm incidence across known risk factors—sex, age, and comorbidities.

The researchers found an increased rate of aortic aneurysms within 90 days in 9 million patients prescribed an oral fluoroquinolone versus 35 million prescribed a comparator antibiotic. The median age of adults with fluoroquinolone fills was 47 years versus 43 years with comparator antibiotic fills. Women comprised 61.3% of fluoroquinolone fills and 59.5% of comparator antibiotic fills. Before weighting, the 90-day incidence of newly diagnosed aneurysm was 7.5 cases per 10,000 fills after fluoroquinolones, compared with 4.6 cases per 10,000 fills after comparator antibiotics.

After weighting for demographic characteristics and comorbidities, the researchers found that the risk was significantly higher—31%—for patients receiving fluoroquinolones, with an increased 90-day incidence of abdominal aortic aneurysm, iliac artery aneurysm, and other abdominal aneurysm. In addition, 81% of adults were more likely to undergo aneurysm repair. This association was consistent across adults ages 35 years or older, sex, and comorbidities.