Written by Clay Smith
Fluoroquinolone use was associated with increased risk of developing newly diagnosed aortic aneurysm or dissection.
Why does this matter?
Fluoroquinolone antibiotics are the most commonly prescribed antibiotics, often given for UTI, sinus infection, community acquired pneumonia, or other indications. We know they are associated with tendinopathy and other musculoskeletal problems due to inhibition of collagen production and stimulation of matrix metalloproteinases. So does this mechanism also increase the risk of aortic aneurysm and subsequent rupture?
Ruptured Achilles...exploding aortas
This was a huge Swedish population database with about 360,000 propensity-matched patients in each group either taking an oral fluoroquinolone or amoxicillin. The hazard ratio of newly diagnosed aortic aneurysm or dissection within 60-days of the antibiotic was 1.66. This was largely driven by newly diagnosed aneurysms, not dissections. This means 82 additional people may have these aortic problems diagnosed per million fluoroquinolone prescriptions. Considering 30 million new fluoroquinolone prescriptions per year in the US alone, that could mean almost 2500 more new aortic problems. Could this all be confounding, and more aneurysms were detected because more imaging was done to rule out infection - so called confounding by indication? This may be the case. However, the study used an active comparator (i.e. amoxicillin) which has similar indications to fluoroquinolones in order to reduce the risk of this bias. While this study doesn't prove causation, the association of fluoroquinolones with connective tissue problems makes it very concerning.
Fluoroquinolone use and risk of aortic aneurysm and dissection: nationwide cohort study. BMJ. 2018 Mar 8;360:k678. doi: 10.1136/bmj.k678.
Peer reviewed by Thomas Davis.