If you’ve ever been sick and needed an antibiotic it’s likely that you’ve been offered a Z-pak, a fast acting antibiotic, which has become increasingly popular since its debut in 1992. But, new research has linked the ever so popular 5 day regimen with an increased risk of cardiovascular death.
The Z-pak, known formally as Azithromycin and by its brand name Zithromax, typically does a great, and fast, job of combating such bacterial illnesses as sinus infections and bronchitis, and has long been believed safe and posed no risk to the heart, but new research found in the New England Journal of Medicine has recently claimed otherwise.
Dr. Gregg C. Fonarow, director of the Ahmanson-UCLA Cardiomyopathy Center and co-director of the UCLA Preventative Cardiology Program, told US News that “certain antibiotics, such as erythromycin, have been demonstrated to increase the risk of cardiac arrhythmias [an irregular heartbeat] and sudden death.”
To examine the potential link researchers at Vanderbilt University and the Nashville Veterans Administration Medical Center analyzed Tennessee Medicaid patient records from1992 – the year it was first prescribed in the United States – to 2006.
The study compared records for nearly 348,000 people who took azithromycin with records for people who took other antibiotics (including amoxicillin, which is used to treat the same infections azithromycin treats but is thought to pose no cardiac risk) and those who took no antibiotics at all. The sample size included more than 1.3 million amoxicillin patients—those taking Amoxil, Moxatag, Trimox, Wymox—more than 264,000 people taking Cipro (ciprofloxacin), and another 194,000 patients who were taking Levaquin (levofloxacin), said US News. Another 1.3 million people who were not taking antibiotics were included in the study, as well.
After controlling for confounding factors that might have contributed to cardiovascular problems, the researchers found a clear increase in risk of cardiovascular death among the Z-pak users compared to those on amoxicillin and those taking no antibiotics.
Patients taking azithromycin were at 2.5 times greater risk of cardiovascular death than those taking amoxicillin or those taking no antibiotic. That risk was elevated only during the five-day treatment period.
“For patients with elevated cardiovascular risk, the cardiovascular effects of azithromycin may be an important clinical consideration,” study author Wayne Ray, a professor of preventive medicine at the Vanderbilt University School of Medicine, told US News. “All antibiotics have risks and benefits, which must be considered in the prescribing decision.”
The overall risk of cardiac death was very small. Still, there were 47 more cardiovascular deaths per million courses of treatment among people taking azithromycin compared to the amoxicillin-taking group. And among people already at high risk for cardiovascular problems, that number rose to 245 added cardiovascular deaths per million. The study did not prove a cause-and-effect relationship.
“People need to recognize that the overall risk is low,” said Dr. Harlan Krumholz, a Yale University health outcomes specialist who was not involved in the study. More research is needed to confirm the findings, but still, he said patients with heart disease “should probably be steered away” from Zithromax for now.
Zithromax is marketed by Pfizer Inc. Pfizer issued a statement saying it would thoroughly review the study. “Patient safety is of the utmost importance to Pfizer and we continuously monitor the safety and efficacy of our products to ensure that the benefits and risks are accurately described,” the company said.
No comments yet.