ED patients who used cocaine with cannabis had higher 3-year mortality than other patients | Research

The takeaway

A study of 1,669 emergency department patients found that use of cocaine and cannabis, both individually and in combination, was associated with significantly higher 36-month mortality risk compared to other ED patients.

Read this if you are interested in the mortality risks associated with combined cannabis and cocaine use.

Cocaine and cannabis use each independently associated with higher 36-month mortality

What the researchers found

Researchers surveyed 1,669 patients from two urban emergency departments and tracked mortality over 36 months using the National Death Index.

The use of cocaine and cannabis, both individually and in combination, was associated with significantly higher mortality risk compared to other ED patients after controlling for demographics.

This mortality risk was present whether cocaine and cannabis were used separately or together, suggesting that both substances independently contribute to elevated risk in this population.

The authors noted that further research was needed to determine whether these results were stable across racial and ethnic groups.

Why it matters

Emergency department patients who use substances represent a high-risk population. Quantifying the mortality risk associated with specific substance use patterns helps prioritize intervention efforts and informs clinical decision-making during ED visits.

The numbers in context

1,669 ED patients surveyed. 36-month follow-up (2009-2012). Cocaine and cannabis use, individually and combined, associated with significantly higher mortality. Used ASSIST screening tool for risk categorization.

How the study worked

Prospective cohort of 1,669 patients from 2 urban EDs surveyed using the ASSIST screening tool. 36-month mortality data obtained from the National Death Index (2009-2012). Cox regression modeled mortality by drug risk groups, controlling for demographics.

What this study cannot tell us

ED patients are not representative of the general population. Mortality associations do not establish causation; substance users may have other risk factors driving mortality. The study could not fully separate the effects of polysubstance use. Specific causes of death were not detailed. Relatively small sample for mortality outcomes.

How to read the evidence

Prospective cohort with mortality tracking provides moderate evidence, limited by inability to establish causation and potential confounding from other risk factors.

When this study was published

Published in 2018 with 2009-2012 mortality data. Substance use patterns in ED populations have continued to evolve.

The bigger picture

This study provides mortality data for a real-world clinical population. The finding that cannabis use is associated with elevated mortality in ED patients, independent of cocaine, adds to the limited literature on cannabis-related mortality risk in high-risk populations.

Questions still open

What are the primary causes of death among substance-using ED patients? Does the mortality risk differ by frequency and amount of cannabis or cocaine use? Would substance use intervention in the ED reduce subsequent mortality?

Common questions

Does using cannabis increase mortality risk?

In this study of ED patients, cannabis use was associated with higher 36-month mortality. However, ED patients who use substances may have many other risk factors contributing to mortality, and this association does not prove cannabis itself caused the increased risk.

Is combining cannabis and cocaine more dangerous?

Both cannabis and cocaine individually were associated with higher mortality in this ED population. The combination was also associated with higher risk, but the study found each substance contributed independently rather than synergistically.

Read the original research

Mortality risk in a sample of emergency department patients who use cocaine with alcohol and/or cannabis.

Substance abuse, 39(3), 266-270

View on PubMed ↗Publisher’s paper ↗

Citation

Gilmore, Devin; Zorland, Jennifer; Akin, Joanna; Johnson, J Aaron; Emshoff, James G; Kuperminc, Gabriel P. (2018). Mortality risk in a sample of emergency department patients who use cocaine with alcohol and/or cannabis.. Substance abuse, 39(3), 266-270. https://doi.org/10.1080/08897077.2017.1389799