Marijuana, Cocaine, Opiate, and Amphetamine Use Associated With Increased Risk of Atrial Fibrillation

Jennifer Middleton, MD, MPH
Posted on February 27, 2023

A large retrospective cohort study published at the end of 2022 examined the risk of developing atrial fibrillation (AF) in people with a history of marijuana, cocaine, opiates, and amphetamines. The study authors found an increased risk of AF with use of each of those substances; while we await more definitive prospective data, family physicians may still wish to counsel patients about this potential risk.

The study authors examined a database of more than 23 million people in the U.S. state of California who had sought care at an emergency department, ambulatory surgery center, and/or hospital between 2005-2015. They looked at “International Classification of Disease, Ninth Revision (ICD-9) and 21 Current Procedural Terminology (CPT) codes” to divide the database population into those with a diagnosis code for AF and those without. They compared the rates of marijuana, cocaine, opiates, and amphetamines between these two groups and found that people with an ICD-9 code for marijuana, cocaine, opiate, and/or amphetamine use had a higher risk of an AF diagnosis than those without an ICD-9 code for one of those substances. They controlled for more than 20 potential confounding variables including socioeconomic status, age, race/ethnicity, and several comorbid conditions (including cardiovascular disease, diabetes, and obstructive sleep apnea). "After adjusting for...covariates, methamphetamine use was associated with increased incidence of AF with hazard ratios (HRs) of 1.86 (95% CI 1.81–1.92), the highest association among the four substances investigated.” Cocaine use had the next highest HR (95% CI), 1.61 (1.55–1.68), followed by opiate use (HR 1.74 [1.62–1.87]) and marijuana use (HR 1.35 [1.30–1.40]). The HR for marijuana use is similar to what has previously been found for tobacco use; the postulated pathophysiology is similar for both, as “[p]articulate matter inhalation increases inflammation, and inflammation is a known trigger for AF.”

As a retrospective cohort, this study can only demonstrate correlation, not causation. It’s possible that not all people using one or more of these substances had an ICD-9 code attached to their billing encounter; it’s likely that not all patients disclosed their substance use to their physician, and, even if they did, perhaps not all physicians added the relevant ICD-9 diagnosis code. This study also provides no information about the potential utility of screening for AF in persons who use these substances. In the meantime, however, it still may be prudent to counsel our patients about this potential risk, especially as marijuana is increasingly legalized across the United States and the opiate epidemic rages on.

There are AFP By Topics on Atrial Fibrillation, Substance Use Disorders, and the Opioid Epidemic – Key Resources if you’d like to read more.