Fluoroquinolones Do Not Increase Risk of Aortic Aneurysm or Dissection, claims Study

Due to their broad-spectrum antibacterial activity, FQs are widely prescribed, but studies have raised concern that they might weaken vascular integrity and thus may be involved in AA/AD. However, no large international study had properly assessed this risk. In this regard, a comprehensive retrospective cohort study was performed to analyze data from 14 databases across the United States, South Korea, Japan, Taiwan, and Australia. The main objective was to determine whether FQ use for UTIs in outpatient settings increases the risk of AA/AD compared with other commonly used antibiotics, such as trimethoprim (TMP) with or without sulfamethoxazole and cephalosporins (CPHs).

The study evaluated data from 13,588,837 patients aged 35 years or older who started systemic FQ or similar antibiotics between January 1, 2010, and December 31, 2019. Patients had at least 365 days of prior observation and were not hospitalized within 7 days of starting antibiotic treatment. Investigators estimated the risk of AA/AD within 60 days of exposure to antibiotics by applying Cox proportional hazards models and using 1:1 PS matching. A Bayesian random-effects meta-analysis pooled HRs to draw conclusions between databases with good statistical validity.

Key Findings

• The authors used 1,954,798 propensity-matched pairs of FQ versus TMP and 1,195,962 for FQ vs. CPH.

• There was no significant increase in the risk of AA/AD among patients receiving FQ compared to TMP (absolute rate difference [ARD]: 0.21 per 1000 person-years; calibrated HR: 0.91, 95% CI 0.73–1.10).

• Similarly, no elevated risk was found when comparing FQ to CPH (ARD: 0.11 per 1000 person-years; calibrated HR: 1.01, 95% CI 0.82–1.25).

• The outcomes of the results were calibrated with those of negative controls to ensure that the information is valid, and all reported analyses met the predetermined diagnosis criteria.

The study authors concluded that FQs do not increase the risk of aortic aneurysm or dissection when used for UTI treatment in outpatient settings. The study's findings reinforce the safety profile of FQs and provide clarity for both clinicians and patients concerned about their vascular effects.

Reference:

Janetzki, J. L., Kim, J. H., Minty, E., Lee, J. A., Morales, D. R., Khera, R., Kim, C., Alshammari, T. M., DuVall, S. L., Matheny, M. E., Falconer, T., Kim, S., Phan, T.-P., Nguyen, P.-A., Hsu, M.-H., Hsu, J. C., Park, R. W., Man, K. K. C., Seager, S., … Chan You, S. (2025). Risk of aortic aneurysm or dissection following use of fluoroquinolones: a retrospective multinational network cohort study. EClinicalMedicine, 81(103096), 103096. https://doi.org/10.1016/j.eclinm.2025.103096