Fluoroquinolone use and serious arrhythmias: A Nationwide Case-Crossover Study

Abstract Aim Fluoroquinolones have been associated with life-threatening ventricular arrhythmias and even sudden cardiac death. We aimed to assess the temporal relationship of fluoroquinolone use and serious arrhythmias via a case-crossover analysis of a large cohort of serious arrhythmias patients. Methods In a national administrative database, we compare the distributions of fluoroquinolone exposure for the same patient across a 30-day period before the serious arrhythmia event and 5 randomly selected 30-day periods before the serious arrhythmia event. Odds ratios (ORs) and 95% Confidence Intervals (CIs) were estimated using conditional logistic regression analysis. Results From a total of 2 million participants, 7657 patients with serious arrhythmias were identified. Use of fluoroquinolones within the 30-day period before the event was significantly associated with increased risk for serious arrhythmia (OR: 3.03, 95% CI: 2.48, 3.71). The risk association was attenuated, but remained significant after adjustment for time-varying confounders (OR: 1.48, 95% CI: 1.18, 1.86). A consistent increase in risk of serious arrhythmia was observed for all time windows investigated (7 days, 14 days, 30 days, 60 days and 90 days). Conclusions Exposure to fluoroquinolones was substantially associated with serious arrhythmic events, independent of the temporal proximity of fluoroquinolone prescription.