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Published on: February 28, 2012
Effect of clarithromycin versus placebo on risk of atrial fibrillation
Gorm Boje Jensen1,2, Markus Harboe Olsen3,4, Magnus Thorsten Jensen4,5
1Copenhagen City Heart Study, Copenhagen University Hospital - Frederiksberg Hospital.
Insights
A brief clarithromycin course did not increase new atrial fibrillation (AF) in patients with stable heart disease. This finding suggests clarithromycin is safe regarding AF incidence in this population.
Area of Science:
- Cardiology
- Pharmacology
Background:
- The CLARICOR trial indicated potential increased mortality with clarithromycin, possibly due to arrhythmias.
- Atrial fibrillation (AF) is a common arrhythmia and significant cardiovascular risk factor.
Purpose of the Study:
- To investigate the incidence of new-onset atrial fibrillation (AF) following a brief clarithromycin regimen in patients with stable ischemic heart disease.
Main Methods:
- A post-hoc analysis of the CLARICOR trial involving 4,372 patients randomized to clarithromycin or placebo.
- AF incidence was tracked for ten years using national registers.
- Cox proportional hazard models were employed to assess the effect of clarithromycin on AF occurrence.
Main Results:
- During ten-year follow-up, 13.5% of the clarithromycin group and 13.3% of the placebo group developed AF.
- Cox analysis revealed no statistically significant difference in AF incidence between the clarithromycin and placebo groups (HR = 1.09; 95% CI: 0.92-1.29; p = 0.32).
Conclusions:
- A short course of clarithromycin did not elevate the risk of developing new atrial fibrillation in patients with chronic stable ischemic heart disease.
Introduction:
The CLARICOR randomised trial of clarithromycin versus placebo in patients with stable ischaemic heart disease found increased all-cause and cardiovascular mortality after a brief clarithromycin regimen, suggesting a possible arrhythmic effect. As atrial fibrillation (AF) is the most common arrhythmia and a major contributor to cardiovascular morbidity and mortality, we compared the AF incidence in the randomisation groups in a post-hoc analysis.
Methods:
In 1999-2000, a total of 4,372 patients with stable ischaemic heart disease were randomised to a two-weeks course of clarithromycin or placebo. Incident AF episodes were followed for ten years through national registers. Using Cox proportional hazard models and some subsidiary analyses, we assessed the effect of clarithromycin on occurrence of AF.
Results:
Among participants, 285 (13.5%) patients in the clarithromycin group and 271 (13.3%) patients in the placebo group were recorded to have (at least) one AF period during follow-up. The Cox analysis showed no significant difference in AF incidence between groups (HR = 1.09; 95% CI: 0.92-1.29; p = 0.32), consistent with findings in the subsidiary analyses.
Conclusions:
In this post-hoc analysis, a brief course of clarithromycin did not increase the incidence of new AF in participants with chronic stable ischaemic heart disease.
Funding:
The present study was financed by the Copenhagen Trial Unit, Centre for Clinical Intervention Research, the Capital Region, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark.
Clinicaltrials:
gov, NCT00121550.
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