Fluoroquinolone use and serious arrhythmias: A nationwide case-crossover study.

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.