Acute alcohol consumption elevates risk of AF event

Presented as a Late Breaking Clinical Trial at the American College of Cardiology 2021 Scientific Sessions by Gregory M. Marcus MD, Professor of Medicine, UCSF, demonstrated that acute alcohol consumption was associated with an elevated risk of discrete atrial fibrillation (AF) event. This event may appear within several hours of the drink and even one drink may increase the risk of such events.

Alcohol is among the most frequently used medications. In 1983, JAMA published a study that reported alcohol as the most common cause of new AF. Later, data from a trial revealed that there are no statistically significant differences in AF inducibility of alcohol infusion compared with placebo when investigating the near-immediate effects of alcohol. The current data on the association of alcohol and AF development mainly include chronic alcohol use, and there is no evidence on the self-reporting of AF development by acute alcohol consumption. Dr. Marcus and colleagues conducted a trial to assess the real-time relationships between alcohol and the development of AF arrhythmia.

A total of 100 consenting patients with paroxysmal AF, age older than 21 years, with minimum consumption of 1 alcoholic drink per month were included in the trial. Substance and alcohol use disorders were the major exclusion criteria of the study. Eligible patients were monitored by a LifeWatch (https://www.myheartmonitor.com/brand/lifewatch/), which recorded ECG by pressing an activator button, and an ankle-worn transdermal ethanol sensor to monitor alcohol levels for a duration of 4 weeks. Drinking events were patient self-recorded and were validated by finger stick blood tests of phosphatidyl ethanol (PEth) conducted at in-person visits at two and four weeks. Statistical analysis was performed by application of cross-over analysis among those with observed AF.

Among the 100 participants included in the trial, 90% wore the LifeWatch for a minimum of 21 days. Data from the transdermal ethanol sensor illustrated a median of 19 drinks with an interquartile range (IQR) of 10 to 38. AF was recorded at least once in 56 participants. The PEth results were in line with real-time alcohol use (P<0.001) and transdermal ethanol sensor detected events (P=0.032). Alcohol consumption was associated with an elevated risk of AF development with one drink associated with 6-fold greater odds (Odds ratio (OR):6.5; 95CI: [1.9-14.8]) within 4 hours and ≥2 drinks associated with approximately 20-fold greater odds (OR: 19.6, 95%CI: [1.9-206.6]) of AF event, respectively. In addition, alcohol consumption within the past 12 hours, detected by transdermal ethanol sensor, was associated with 85% greater odds of an AF episode.

It is important to consider the limitations of the trial, while interpreting these findings. It is possible that the development of AF occurred as the result of concurrent behavior such as drinking caffeine and smoking. Poor sleep as the result of consuming alcohol was also reported as a mediator for AF induction. Further research is required to understand the interaction between AF and other potential trigger behaviors.