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Fluoroquinolone use and serious arrhythmias: A nationwide case-crossover study
Lorenzo Porta1, Meng-Tse Gabriel Lee2, Wan-Ting Hsu3
1School of Medicine and Surgery, Department of Emergency Medicine, Università degli studi di Milano Bicocca, Milan, Italy.
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.
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