Medical cannabis authorization was linked to higher risk of emergency visits for depression | Research

The takeaway

In a propensity-matched cohort study, patients authorized for medical cannabis had a higher risk of emergency department visits and hospitalization for depressive disorders compared to matched controls.

Medical cannabis prescribers, psychiatrists, patients considering medical cannabis, and regulators overseeing medical cannabis programs.

Medical cannabis authorization linked to higher depression-related emergency care

What the researchers found

Medical cannabis users had significantly higher rates of ED visits and hospitalization for depressive disorders than propensity-matched controls who did not receive medical cannabis authorization.

Why it matters

Medical cannabis is increasingly used for conditions that overlap with depression. If cannabis authorization is associated with increased depression-related emergencies, it has important implications for patient monitoring and informed consent.

The numbers in context

Propensity score-matched cohort. Medical cannabis authorization associated with increased risk of ED visits and hospitalization for depressive disorders.

How the study worked

Retrospective longitudinal cohort study using propensity score matching. Compared patients who received medical cannabis authorization with matched controls on rates of ED visits and hospitalization for depressive disorders.

What this study cannot tell us

Observational design even with propensity matching cannot establish causation. People who seek medical cannabis may have more severe or treatment-resistant conditions. Cannot determine whether cannabis caused, worsened, or simply coincided with depression. Propensity matching may not capture all relevant differences.

How to read the evidence

Propensity-matched retrospective cohort is stronger than unmatched observational data, but residual confounding likely remains.

When this study was published

Published 2023.

The bigger picture

The relationship between cannabis and depression is complex: some people use cannabis to manage depression, but cannabis may also worsen or unmask depressive symptoms. This study suggests the net effect at the population level may not be beneficial.

Questions still open

Does the depression risk differ by cannabis formulation or indication? Would prospective monitoring of mental health in medical cannabis patients prevent emergency presentations?

Common questions

Can medical cannabis make depression worse?

This study found that people authorized for medical cannabis had more emergency visits and hospitalizations for depression than matched controls. However, it cannot prove cannabis caused the depression. People who seek medical cannabis may have more complex health situations that independently increase depression risk.

Should people with depression avoid medical cannabis?

This study adds a cautionary note but does not definitively answer the question. The relationship between cannabis and depression likely depends on many factors including the specific cannabis product, dose, reason for use, and individual biology. Mental health monitoring during medical cannabis use seems prudent.

Read the original research

Risk of depressive disorders associated with medical cannabis authorization: A propensity score matched cohort study.

Psychiatry research, 320, 115047

View on PubMed ↗Publisher’s paper ↗

Citation

Yana, Jerry Liwono; Lee, Cerina; Eurich, Dean T; Dyck, Jason R B; Hanlon, John G; Zongo, Arsène. (2023). Risk of depressive disorders associated with medical cannabis authorization: A propensity score matched cohort study.. Psychiatry research, 320, 115047. https://doi.org/10.1016/j.psychres.2022.115047