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Methamphetamine and cocaine use each confer heightened risk for incident ventricular arrhythmias and all-cause mortality, according to a recent study.

Methamphetamine and cocaine use each heighten risk for incident ventricular arrhythmias (VA) and all-cause mortality, with younger patients and females exhibiting disproportionately greater risk for VA with both stimulants, according to a study published online in European Heart Journal.

“The magnitude of the risk associated with these substances was similar to most well-established cardiovascular risk factors,” noted study author Gregory M. Marcus, MD, MS, University of California-San Francisco, and coauthors. “Unlike many of those risk factors, and with the caveat that physical addiction may limit ready cessation of these drugs, these drugs represent a modifiable risk factor under the immediate control of the user.”

Background & Aims

According to the authors, ventricular tachycardia (VT) and ventricular fibrillation (VF) account for a substantial proportion of sudden cardiac deaths, yet the contribution of modifiable lifestyle factors—particularly illicit stimulant exposure—to their incidence remains inadequately characterized. Methamphetamine and cocaine—the most prevalent nonprescription stimulants in the United States, according to the study—exert sympathomimetic effects that may precipitate VA. The researchers sought to quantify the relationship between methamphetamine and cocaine use and the subsequent risk for incident VA and all‐cause mortality in a large, hospital‐based adult cohort.

Retrospective Cohort Study

The authors conducted a retrospective cohort analysis of all adults (≥18 years) receiving inpatient or emergency care in California from January 2005 to December 2019, using linked administrative databases. Methamphetamine and cocaine exposure were identified via ICD codes. Time‐updated covariates included demographic factors (age, sex, race/ethnicity) and cardiovascular risk profiles (hypertension, diabetes mellitus, hyperlipidemia, chronic kidney disease), as well as comorbid cannabis and opioid use. The co‐primary end points were (1) incident VA (composite of VT, VF, or cardiac arrest) and (2) all‐cause mortality. Multivariable Cox proportional hazards models hazard ratios (HRs) and 95% CIs, incorporating interactions to assess effect modification by age, sex, and race/ethnicity.

Elevated Risks & Disparities Discovered

According to the results, of 29,593,819 individuals (mean age, 44.9 years; 53.8% female), 690,737 (2.3%) had documented methamphetamine use and 290,652 (1.0%) had documented cocaine use. Over a median follow-up of 7.4 years:

• Methamphetamine use was linked to a near doubling of risk for VA (HR, 1.90; 95% CI, 1.85-1.95) and a 51% higher risk for death (HR, 1.51; 95%, CI 1.47-1.54).
• Cocaine use conferred more modest yet statistically significant risk for VA (HR, 1.15; 95% CI, 1.10-1.19) and substantially elevated risk for mortality (HR, 1.68; 95%, CI 1.64-1.72).

Interaction analyses revealed that younger patients (<65 years) and females faced disproportionately greater risk for VA from both stimulants (P for interaction<0.001). Racial and ethnic disparities emerged: cocaine-related risk for VA was highest among Black individuals but lower among White and Hispanic individuals; methamphetamine-related risk for VA peaked in Asian populations and was attenuated in Black populations (all P for interaction<0.05).

Implications for Prevention

The researchers concluded that both methamphetamine and cocaine use independently predict increased incidence of VA and mortality, with distinct demographic patterns.

“These findings stress the importance of avoiding methamphetamine and cocaine to prevent VA and premature death,” the authors stated. “Recognizing and, in the future, better understanding the differences in the impact of these substances across demographic groups may enhance prevention strategies.”