Mosholder AD, et al. - The physicians investigated the long-term risk of acute myocardial infarction, stroke, and death with outpatient use of clarithromycin. This retrospective cohort study concluded that outpatient clarithromycin use was correlated with long-term mortality increases, with evidence for a similar, smaller increase with erythromycin.

• The physicians performed this retrospective cohort study of subjects enrolled in the United Kingdom Clinical Practice Research Datalink from 2000-2013 evaluated long-term risks of death, stroke, and acute myocardial infarction (AMI) in adults prescribed clarithromycin.
• For this study, subjects were outpatients aged 40-85 years.
• They prescribed clarithromycin, doxycycline, or erythromycin (287,748, 267,729, and 442,999 patients, respectively), or H. pylori eradication therapy with a proton pump inhibitor, amoxicillin, and either clarithromycin (27,639 patients) or metronidazole (14,863 patients).
• With Cox proportional hazards regression, they analyzed time to death, stroke, or AMI.

• Following one clarithromycin vs. one doxycycline prescription, the long-term hazard ratio (HR) for death was 1.29 (95% confidence interval (CI) 1.21, 1.25), increasing to 1.62 (95% CI 1.43, 1.84) for 5+ prescriptions of clarithromycin vs. 5+ prescriptions for doxycycline.
• Erythromycin demonstrated smaller risks vs. doxycycline.
• After clarithromycin, stroke and AMI were also increased, but with smaller HRs than mortality.
• The HR for mortality following clarithromycin vs. metronidazole regimens was 1.09 (95% CI 1.00, 1.18) for H. pylori eradication, and was higher (1.65, 95% CI 0.88, 3.08) following 2+ prescriptions in subjects not on statins at baseline.