Misuse of illicit substances such as methamphetamines, cocaine, opiates and cannabis are linked to an increased risk of atrial fibrillation
The misuse of the illicit substances methamphetamine, cocaine, opiates and cannabis has been found to increase the risk of incident atrial fibrillation (AF) according to the findings of a longitudinal analysis by Californian researchers.
Atrial fibrillation is the most frequent cardiac arrhythmia, and it has been estimated that 6 -12 million people worldwide suffer from the condition. Moreover, the presence of the arrhythmia is also independently associated with a higher risk of all-cause mortality. While it has become well established that a higher intake of alcohol as well as smoking, increases the risk of AF, the relationship with the misuse of illicit drugs is less clear. Whereas prior work has suggested that methamphetamine abuse leads to ECG changes that pose a higher risk for ventricular arrhythmias and most notably torsades de pointes, less is known about the effect on AF. However, there is some data linking an increased risk of AF from use of both cannabis and cocaine though these findings are derived from case studies. But in contrast, one study actually identified how cannabis use was associated with a lower odds of AF.
In the present study, the US researchers sought to determine whether misuse of the illicit substances, methamphetamine, cocaine, opiates and cannabis were a predictor of incident AF. The team used several California healthcare databases, e.g., emergency department and inpatient to capture repeat visits for a given patient. They extracted demographic and co-morbidity data and excluded those with known AF and looked at cases where substance use was considered present at the first healthcare encounter. The researchers then compared the baseline and clinical characteristics of patients for each of the different drugs and examined the association with AF, adjusting for covariates known to be associated with AF.
Illicit substance misuse and incident atrial fibrillation
In a total of 23,561,884 individuals, 98,271 used methamphetamine, 48,701 cocaine, 10,032 opiates and 132,834 cannabis. From this total, 4.2% developed incident AF during the period of study from 2005 to 2015. The mean age of participants ranged from 32.3 years (cannabis) to 41.1 (cocaine) and the proportion of females from 28.3% to 55%.
After adjustment for covariates, methamphetamine use was associated with an 86% higher risk of developing incident AF (Hazard ratio, HR = 1.86, 95% CI 1.81 – 1.92). Similar and significantly elevated risks were seen for cocaine (HR = 1.61), opiates (HR = 1.74) and cannabis (HR = 1.35). Interesting, polysubstance use was also associated with a higher risk of AF compared to single drug misuse (HR = 1.63, 95% CI 1.61 – 1.66).
The authors concluded that for each of the misused substances analysed, there was a higher risk of developing incident AF after controlling for conventional AF risk factors.
Lin AL et al. Cannabis, cocaine, methamphetamine, and opiates increase the risk of incident atrial fibrillation. Eur Heart J 2022