Data from the U.S. Food and Drug Administration’s adverse reporting system plus a private insurance health claims database in the U.S. that captures demographics, drug identification, dose prescribed and treatment duration, identified 12,505 cases of valvular regurgitation with 125,020 case-control subjects in a random sample of more than nine million patients.
It found that current users of fluoroquinolone antibiotics, such as Ciprofloxacin or Cipro, face a 2.4 times greater risk of developing aortic and mitral regurgitation, where the blood backflows into the heart, compared to patients who take amoxicillin, a different type of antibiotic. The greatest risk is within 30 days of use.
They defined current fluoroquinolone exposure as an active prescription or 30 days prior to the adverse event, recent exposure as within days 31 to 60, and past exposure as within 61 to 365 days prior to an incident. Scientists compared fluoroquinolone use with amoxicillin and azithromycin.
The results showed that the risk of aortic and mitral regurgitation, blood backflow into the heart, is highest with current use, followed by recent use. They saw no increased risk aortic and mitral regurgitation with past use.
Physicians prefer fluoroquinolones over other antibiotics for their broad spectrum of antibacterial activity and high oral absorption, which is as effective as intravenous, or IV, treatment, coupled with ease of use, which makes patients more likely to stick to the schedule.
“You can send patients home with a once-a-day pill,” says Mahyar Etminan, lead author and associate professor of ophthalmology and visual sciences in the faculty of medicine atUniversity of British Columbia. “This class of antibiotics is very convenient, but for the majority of cases, especially community-related infections, they’re not really needed. The inappropriate prescribing may cause both antibiotic resistance as well as serious heart problems.”
The researchers hope their study helps inform the public and physicians that if patients present with cardiac issues, where no other cause has been discovered, fluoroquinolone antibiotics could potentially be a cause.