High-quality human clinical trials needed to determine the benefits of CBD for heart disease patients

As cannabidiol (CBD) use rises, high-quality randomized clinical trials are needed to determine if anti-inflammatory benefits of CBD for heart disease seen in preclinical data will work in a real-world setting, according to research presented at ACC Latin America 2022 Together with CardioAcademic. A review of existing studies found no clinical recommendations can be made given current evidence. ACC Latin America 2022 Together with CardioAcademic will be held in Mexico City on September 9-10, 2022.

"Cannabidiol and medical cannabis use, alongside its many products, has increased considerably in the last decade. Nonetheless, there are few indications for its use based on good clinical trials. Here we seek to provide preclinical evidence, which ultimately serves as the cornerstone to establishing well-designed clinical trials in humans to prove the effect of CBD on coronary syndromes with strong scientific evidence," said Mario Esteban Zúñiga Ayala, MD, a cardiology fellow at Hospital Regional 1 ^o de Octubre ISSSTE in Mexico City and the study's primary author. "CBD has substantial evidence for the following conditions: pain, cachexia, nausea and vomiting, multiple sclerosis spasticity and, most recently, epilepsy. Its pharmacological profile shows it is safe and well-tolerated in humans, although it has well-described side effects. But the interaction with other medications often used by cardiologists, such as anticoagulation and anti-platelet drugs, is not well-known."

CBD is derived from Cannabis species, commonly called marijuana, with non-psychoactive activity. It also has analgesic, anti-inflammatory, antineoplastic and chemopreventive activities. According to the researchers, trends indicate that marijuana is the most used substance compared to other drugs like cocaine, heroin, etc. As usage grows, many heart disease patients may consider using these products.

"Medical marijuana and CBD may be of interest as it is advertised and anecdotally distributed as a treatment for many conditions with possible and inconclusive evidence like glaucoma, Alzheimer's disease, Parkinson's disease, anxiety and depression, inflammatory bowel disease and many other conditions that lack clinical data," Zúñiga Ayala said.

Due to the anti-inflammatory properties of CBD, the study sought to examine its potential role in reducing myocardial ischemia, a condition in which reduced blood flow to the heart may result in chest pain, heart failure and heart attack as the heart works harder to pump blood and oxygen. The researchers used the "Preferred Reporting Items for Systematic Reviews and Meta-Analysis" guidelines to perform a systematic search of the PubMed database up to April 2022 using predefined search terms. Nine preclinical studies were included in the review, but no quality randomized control trials (RCTs) for the use of CBD in acute or chronic coronary syndromes were found.

A review of the nine preclinical studies found reproducible cardiovascular outcomes in in-vivo studies with CBD. Some of the mechanisms for the findings included reduction in oxidative stress and inflammation.

"CBD also showed promising results in experimental models of ischemia and reperfusion lesion, myocardial infarction, arrhythmias and metabolic syndrome-like conditions," Zúñiga Ayala said.

According to the researchers, preclincal evidence on CBD and its use in ischemic heart disease is robust enough to propose well-designed clinical trials in humans in the setting of coronary syndromes.

"CBD is not a miraculous drug. If taking any other medications, try to seek a specialist on medical cannabis to advise you if you are a candidate to take CBD. Always ask for interactions with your previously prescribed medications and do not suspend any drug prescribed by your physician," Zúñiga Ayala said. "If buying CBD always look for well-established dispensaries. Clinicians should be aware of the unreliability, purity and dosage of CBD in products. A recent study of 84 CBD products bought online showed that more than a quarter of the products contained less CBD than labeled. In addition, THC was found in 18 products. THC containing products could potentially cause harm to heart disease patients."