Use Of Drug To Help Stop Smoking May Increase Risk For Cardiovascular Events

One of the most widely prescribed drugs to assist people quit smoking called varenicline may be putting people at an increased risk of cardiovascular events according to research published in American Journal of Respiratory and Critical Care Medicine.

Canadian researchers have reported that in an observational self controlled trial where patients were prescribed varenicline, also known as champix and chantix, 34% of the patients were more likely to require an E.R department visitation or hospitalization for a cardiovascular event while taking the prescribed varenicline, among these patients those who had not previously experienced an event the increase of incidence was only 12%. It is estimated that among all patients there were 3.95 adverse cardiovascular events per 1000 prescribed users.

Medical records of 56,851 new users of varenicline were analyzed by researchers over a period of 4 years, studying a year prior to and a year after the date when the drug was prescribed and finished. During that time frame 4,185 patients had experienced one or more cardiovascular events and 4,720  patients had experienced one or more neuropsychiatric events that required an emergency room department visit or hospitalization.

Varenicline is generally used for 12 weeks, with the patients serving as their own control, with those weeks being considered as the risk interval being compared to the previous weeks prior to initiation of treatment and after should the treatment have been ended. 6 weeks previous to beginning varenicline treatment were excluded from the control period to avoid biasing results by including patients who had just suffered an event and started varenicline to reduce their risk of another.

Cardiovascular events included events such as stroke, unstable angina, arrhythmias, peripheral vascular disease, heart attacks, and others. Among the neuropsychiatric events anxiety, psychosis, self harm, insomnia, depression, and hallucinations were included.

Cause and effect is not able to be determined because this was an observational study. There were some factors limiting this study including things such as not having all the information about if the patients had taken any other medications to help quit smoking, when the patients had quit smoking, or whether the withdrawal of nicotine had accounted for some of the neuropsychiatric events that were reported.

Studies by other researchers have found that varenicline can triple the odds of an individual being able to quit smoking effectively. Long term benefits of that need to be taken into consideration when weighing the potential risks of taking varenicline for 12 weeks. However, the study shows that physicians should monitor patients who are taking varenicline closely to for signs of adverse effects to catch potential events early before they happen if they do occur.