More research needed on cannabis use and transplant survival, say experts

Researchers from Indiana University School of Medicine have suggested that the medical and scientific establishment should expand and re-contextualise its understanding of cannabis use and heart transplantation.

Posing the potential for a completely new approach to determining transplant candidacy, the team’s findings have been published in the journal Circulation: Heart Failure.

The paper drew from an analysis of more than 200 publications, reviews pre- and post-heart transplant considerations related to cannabis use and compares relative clinician attitudes toward cannabis and opiates.

Read more: Cannabis and heart health – potential risk or protective agent?

Lead author Onyedika Ilonze, MD, assistant professor of medicine at IU School of Medicine and member of the Cardiovascular Institute, has emphasised that transplantation is a life-saving option for patients with end-stage heart failure. 

However, unanswered questions surrounding the legality and acceptability of cannabis use has prevented many patients from receiving transplants. Whether people who use cannabis should be considered candidates for transplant is controversial, Ilonze said.

“This is a dilemma in a time of increasingly favorable legislation regarding medical and recreational cannabis use,” said Ilonze. “The dilemma is compounded by a rising need for heart transplants.”

Read more: Prescribed cannabis linked with ‘small risk’ of heart problems

The findings demonstrated that the reasons clinicians choose not to pursue transplantation in patients who use cannabis are based on old data, or have no scientific basis.

Ilonze continued: “Clinician bias, lack of consensus, and a dearth of research limit standard decision-making and worsen disparities in heart transplantation.

“We need to learn more about the interactions between cannabis and immunosuppressants, and to study the association between cannabis use and transplant survival.

“Clarifying this will move us forward and help us establish a standardised evaluation process.”

Khadijah Breathett, MD, is an associate professor of medicine and the director of health equity research at the Cardiovascular Institute, who was also involved in this work. 

Breathett said that the paper is the starting point for Ilonze to develop a research programme that scientifically and ethically addresses the rising use of cannabis in heart transplant candidates and recipients.

“Dr Ilonze is performing culture-shifting work as an early career investigator,” Breathett said.

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