Study Questions Link Between Common Antibiotic and Ventricular Arrhythmia

Azithromycin does not appear to be associated with increased risk of ventricular arrhythmia (VA), according to the results of a recent case-control study.

The relationship between VA and azithromycin is controversial.
_______________________________________________________________________________________________________________________________________________________________________

RELATED CONTENT
Could Caffeine Induce Arrhythmias in Patients with Heart Failure?
Study Uncovers Physiological Process Behind Heart Arrhythmias
_______________________________________________________________________________________________________________________________________________________________________

To further explore this association, researchers conducted a nested case-control study involving a cohort of new antibiotic users from 7 healthcare databases in Denmark, Germany, Italy, the Netherlands, and the United Kingdom, with up to 100 controls per case matched by age, sex, and database.

Overall, 14,040,688 new antibiotic users were identified. VA developed in 12,874 individuals, of which, 30 were current azithromycin users. In pooled data analyses, azithromycin use was associated with an increased risk of VA compared with nonuse of antibiotics. However, this association was not present when comparing current azithromycin users with current amoxicillin users.

“Current azithromycin use was associated with an increased risk of ventricular arrhythmia when compared with nonuse of antibiotics, but not when compared with current amoxicillin use. The decreased risk with an active comparator suggests significant confounding by indication,” the researchers concluded.

—Michael Potts

Reference:

Trifiro G, Ridder M, Sultana J, et al. Use of azithromycin and risk of ventricular arrhythmia [published online April 18, 2017]. CMAJ. doi:10.1503/cmaj.160355