Among 1.3 million VA patients on opioids for pain, more opioid prescriptions were associated with higher rates of cannabis use disorder

In a national sample of over 1.3 million veterans receiving opioids for non-cancer pain, more opioid prescriptions were associated with greater likelihood of having a cannabis use disorder.

Hefner, Kathryn et al.·The American journal on addictions·2015·Moderate EvidenceCross-Sectional
RTHC-00976Cross SectionalModerate Evidence2015RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Researchers examined cannabis use disorder (CUD) rates among 1,316,464 VHA patients with non-cancer pain who received opioid medications. Using logistic regression controlling for confounders, they found that greater numbers of opioid prescription fills were associated with greater likelihood of having a CUD diagnosis.

The relationship held across prescription fill categories (0, 1-2, 3-10, 11-19, 20+), though it was somewhat reduced for those receiving the most prescriptions (20+) after controlling for confounders like other substance use disorders and psychotropic medications.

The authors concluded that cannabis and opioids appear to function as complements (associated with increased use of both) rather than substitutes (where more of one means less of the other), warranting increased clinical attention to cannabis use in patients receiving opioid prescriptions.

Key Numbers

1,316,464 VHA patients analyzed. More opioid fills associated with more CUD. Relationship held across fill categories: 0, 1-2, 3-10, 11-19, 20+. Slightly attenuated at 20+ fills after adjustment.

How They Did This

Cross-sectional analysis of 1,316,464 VHA patients with non-cancer pain diagnoses receiving opioid medications in fiscal year 2012. Bivariate and logistic regression analyses examined the relationship between number of opioid prescription fills and CUD diagnosis.

Why This Research Matters

The substitution hypothesis (that cannabis could replace opioids and reduce the overdose epidemic) is a major policy argument. This study provides contrary evidence: in practice, cannabis and opioid use appear to go together rather than substitute for each other.

The Bigger Picture

The cannabis-opioid substitution debate has major policy implications. This large-scale observational study suggests that in a real-world clinical population, the relationship is complementary rather than substitutive, though the study design cannot determine causation.

What This Study Doesn't Tell Us

Cross-sectional design cannot determine temporal direction. VHA patient population (predominantly male, older, with high comorbidity) may not generalize. CUD diagnosis may be underreported. Cannot determine whether patients used cannabis to manage pain or for other reasons.

Questions This Raises

  • ?Do patients use cannabis to manage pain that opioids inadequately control?
  • ?Would controlled cannabis access reduce opioid prescriptions, or would it add another substance to the mix?
  • ?Does the complementary pattern hold in non-veteran populations?

Trust & Context

Key Stat:
1.3 million patients: more opioid fills = more cannabis use disorder
Evidence Grade:
Large national cross-sectional analysis with statistical controls, but cannot establish causal direction.
Study Age:
Published in 2015 using fiscal year 2012 VHA data.
Original Title:
Concomitant cannabis abuse/dependence in patients treated with opioids for non-cancer pain.
Published In:
The American journal on addictions, 24(6), 538-45 (2015)
Database ID:
RTHC-00976

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Does cannabis replace opioids for pain?

This large VA study found the opposite pattern: patients with more opioid prescriptions were more likely to also have cannabis use disorder, suggesting the two substances complement rather than substitute for each other.

Should doctors screen for cannabis use in opioid patients?

The authors recommended increased attention to cannabis use disorders among patients receiving numerous opioid prescriptions, as the two substances appeared to be used together rather than one replacing the other.

Read More on RethinkTHC

Cite This Study

RTHC-00976·https://rethinkthc.com/research/RTHC-00976

APA

Hefner, Kathryn; Sofuoglu, Mehmet; Rosenheck, Robert. (2015). Concomitant cannabis abuse/dependence in patients treated with opioids for non-cancer pain.. The American journal on addictions, 24(6), 538-45. https://doi.org/10.1111/ajad.12260

MLA

Hefner, Kathryn, et al. "Concomitant cannabis abuse/dependence in patients treated with opioids for non-cancer pain.." The American journal on addictions, 2015. https://doi.org/10.1111/ajad.12260

RethinkTHC

RethinkTHC Research Database. "Concomitant cannabis abuse/dependence in patients treated wi..." RTHC-00976. Retrieved from https://rethinkthc.com/research/hefner-2015-concomitant-cannabis-abusedependence-in

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.