Misuse of illicit substances linked to higher risk of atrial fibrillation

2nd November 2022

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.

Citation
Lin AL et al. Cannabis, cocaine, methamphetamine, and opiates increase the risk of incident atrial fibrillation. Eur Heart J 2022

US study reveals different clinical concerns among substance misuse ED visits

31st March 2022

An analysis of ED visits for people with substance misuse problems has found marked differences in the main presenting clinical concerns

There appear to be clear differences in the most frequently encountered clinical concerns among patients with substance misuse problems presenting at an emergency department (ED). This was the key finding of a study by researchers from the National Clinician Scholars Program, Philip R. Lee Institute for Health Policy Studies, University of California, USA.

Although opioid overdose deaths during the COVID-19 pandemic increased, research suggests that there has been little change to the number of opioid-related ED visits during the early pandemic.

Moreover, there have also been increases observed for other substance misuse drugs, for instance, methamphetamine-related admissions found to have increased from 15.1% in 2008 to 23.6% in 2017.

While the proportion of visits for psycho-stimulants has increased, a further concern has been how the mortality rate involving all stimulants has also risen from 2.91 deaths per 100 000 population in 2010 to 9.69 in 2017.

Despite this increased mortality rate, not all visits are fatal and it is more important to recognise the acute toxicity associated with stimulant use. For instance, one study of 137 cocaine users found that patients had a wide range of clinical symptoms including altered mental status (40%), chest pain (21%), syncope (19%), suicide attempt (13%), palpitations (12%) and seizures (12%).

To date, few studies have examined the prevalence of the clinical symptoms exhibited by psycho-stimulant and cocaine users who present at an ED and how this compares with opiate or opioid users.

For the current study, the US team examined not only the annual trends in substance misuse presentations at ED, but also whether there were differing clinical concerns, particularly for psycho-stimulant and cocaine visits in comparison to those with opiate-related problems.

The team examined only adult ED visits for cocaine, psycho-stimulants and opiate use and excluded those cases for which the hospital records documented two or more drugs. The primary exposure of interest was the type of drug associated with the ED visit and the primary outcome of interest was the chief presenting concerns based on four categories: psychiatric; neurologic; cardiopulmonary or drug toxicity/withdrawal concerns.

Substance misuse and clinical concerns

The study included 7,121,000 weighted ED visits between 2008 and 2018. The rate of cocaine-related visits changed very little over time and increased from 6.6 visits/10,000 population in 2008 to 8.9 visits/10,000 in 2018 (p = 0.23). In contrast, psycho-stimulant visits increased from 2.2 to 12.9 visits/10,000 over the same period of time (p < 0.001) and opiate-related visits increased the most, from 6 to 24.8 visits/10,000 (p < 0.001).

The chief presenting concern varied between the three drugs. Among opiate-related visits, an ‘adverse effect of drug abuse‘ occurred with 27.9% of all visits, whereas with cocaine, ‘chest pain‘ occurred in 27.2% of visits, although chest pain was the most common concern (10.4%) among psycho-stimulant users.

Among the three classes of drugs, compared to opiate-related visits, psycho-stimulant use was significantly associated with a higher odds of psychiatric concerns (odds ratio, OR = 2.69, 95% CI 1.83 – 3.95) and cardiopulmonary concerns (OR = 2.46, 95% CI 1.42 – 4.26).

This elevated risk was also significant for cardiopulmonary concerns in cocaine-related visits (OR = 2.95, 95% CI 1.70 – 5.13) but not for psychiatric concerns. In contrast, psycho-stimulant-related visits for drug toxicity/withdrawal were significantly less than for opiate-related visits (OR = 0.47, 95% CI 0.30 – 0.73).

The authors concluded that psycho-stimulant and cocaine-related ED visits required more attention for cardiopulmonary and psychiatric complications as opposed to opiate-related visits which were largely because of drug toxicity or withdrawal problems.

Citation
Suen LW et al. Emergency department visits and trends related to cocaine, psychostimulants, and opioids in the United States, 2008–2018 BMC Emerg Med 2022