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Sunday, October 8, 2023

In a nationwide cohort of patients with chronic pain, the use of medical cannabis was associated with a 64% risk increase of arrhythmias compared with no use. This poses a potential health concern and is vital knowledge for any physician prescribing medical cannabis. The use of medical cannabis was not associated with an elevated risk of ACS or HF.


Many cannabis users are familiar with trichomes. A tiny little crystal you’ll find on the leaves and buds of cannabis flower. Trichomes are minuscule in size, but they impact marijuana in a huge way. If you want your cannabis to have a lovely flavor and aroma– and a good amount of CBD or THC– you want your cannabis to have some well-tended trichomes.  Trichomes are tiny growths that can be found on certain plants, including algae, lichens, and cannabis plants. The word trichome comes from the Greek word “trichōma,” which means “growth of hair.” This is a fitting name for trichomes. As they look a bit like tiny, frosty, sparkly hairs that cover a plant. While cannabis trichomes are not hairs, they do grow out of the cannabis plant much like a hair would. Springing from the plant’s surface during the flowering phase.  

What do trichomes do?

In a nationwide cohort of patients with chronic pain, the use of medical cannabis was associated with a 64% risk increase of arrhythmias compared with no use. This poses a potential health concern and is vital knowledge for any physician prescribing medical cannabis. The use of medical cannabis was not associated with an elevated risk of ACS or HF.

As the stigma surrounding cannabis wanes and its potential medicinal value becomes more widely accepted, an increasing number of people are turning to the plant for both recreational and therapeutic purposes. However, despite its growing popularity, our understanding of how cannabis affects the human body is still limited. While a body of evidence points to the therapeutic potential of cannabis, it is important also to consider the potential risks associated with its use. A study by Holt et al. presented at the 43rd European Society of Cardiology Congress


Treatment with medical cannabis for chronic pain is in popular demand, and a rising number of countries allow physicians to prescribe medical cannabis for pain management. However, data on drug safety is scarce. Studies have shown a risk of cardiovascular side effects following the use of recreational cannabis warranting further investigations into the safety of prescribing medical cannabis.


last fall, for instance, suggested a possible link between cannabis use and an increased risk of cardiovascular events, bringing into question its safety.

About the Study 


Holt and colleagues conducted an observational study to examine the potential risk of cardiovascular events in 4,562 patients with chronic pain who were prescribed medical cannabis (cannabinoid, cannabidiol, or dronabinol) compared to a control group who weren’t taking the medication. Specifically, they looked at the risk of new-onset arrhythmias (abnormal heart rhythms), acute coronary syndrome (ACS, a condition caused by the sudden, reduced blood flow to the heart), and heart failure. The researchers used the Danish national registers to follow the cohort, who, importantly, did not have a history of arrhythmias, ACS, heart failure, or medical cannabis use prior to the study period (2018 to 2021). Patients from the exposed cohort were matched to controls in age group, sex, and chronic pain diagnosis. 

The study found that the risk of new-onset arrhythmias was higher in the group prescribed medical cannabis compared to the control group, with a risk ratio of 1.64 (95% CI: 1.04-2.23) – a 64% relative risk increase. The 180-day absolute risks were 0.71% (95% CI: 0.47%-0.94%) for exposed subjects vs. 0.43% (95% CI: 0.37%-0.49%) for controls, indicating an absolute risk increase of 0.28% with cannabis use. This 0.28% absolute risk increase translates to one case of arrhythmia for every 360 users. However, the risk of ACS or heart failure was not elevated in the group prescribed medical cannabis compared to the control group. 

A cause for alarm? 

Given the lack of human data on medical cannabis and potential cardiovascular risks, these findings are certainly noteworthy. However, upon closer examination, the limitations of the study suggest that there may not yet be cause for alarm.


One potential source of selection bias in this study is the difference in comorbidities between the exposed and control groups. Comorbidities refer to the presence of health conditions that an individual may be experiencing in addition to their “main” condition or the condition of interest within the study. In this study, the exposed group had more comorbidities, including hypertension, ischemic heart disease, chronic kidney disease, and diabetes mellitus, than the control group, which could potentially affect the results if the exposed group was more vulnerable to certain adverse events due to their overall health status. For example, in patients with hypertension, the heart muscle may enlarge (a condition known as cardiac hypertrophy), which can also involve the growth of fibrous tissue and a decrease in connectivity between cells. These changes can disrupt the normal electrical properties of the heart and increase the likelihood of arrhythmias. 


Another source of selection bias in this study is the fact that the exposed group had higher exposure to other medications compared to the control group. Other medications taken by the exposed group may interact with medical cannabis, altering the effects of both on the body and impacting susceptibility to CV concerns. It is also possible that other medications, if metabolized by the same enzymes in the body as CBD, could potentially interfere with the absorption, distribution, metabolism, and elimination of both substances. Notably, a significantly higher percentage of the exposed group (42.2%) were also taking opioid medications compared to the control group (12.3%). CBD has been shown to inhibit CYP2D6, an enzyme involved in the metabolism of opioids such as oxycodone, which may lead to an increase in the serum concentrations of these medications. In 2019, research by Dashi et al. revealed a link between opioid overdose and the occurrence of ischemic events, heart failure, and arrhythmias in patients hospitalized due to opioid overdose. Additionally, a review by Behzadi, Joukar, and Beik suggests that opioids can themselves trigger arrhythmias, and higher doses of these medications may exacerbate this effect.

The Bottom Line

Holt et al. showed that medical cannabis use was associated with a small increase in the risk of arrhythmias, but the presence of major confounds in this study stymies any meaningful interpretation of these findings with respect to the effects of cannabis per se. Those with pre-existing cardiovascular conditions may want to proceed with caution in light of the possibility that medical cannabis negatively impacts CV health, but ultimately, more research is needed.


Friday, October 6, 2023

FDA ‘remains unsatisfied’ with Philips’ handling of CPAP recall




We do not believe that the testing and analysis Philips has shared to date are adequate to fully evaluate the risks posed to users from the recalled devices,” the FDA's device center director, Jeff Shuren, said in an update this week. (Photo by Sarah Silbiger/Getty Images)


Since Philips began its recall of millions of respiratory devices in June 2021, the FDA hasn’t been shy about criticizing how the company has handled the recall.

Certain Philips Respironics ventilators, bilevel positive airway pressure (BiPAP) machines, and continuous positive airway pressure (CPAP) machines

And over two years in, despite Philips’ efforts, the agency “remains unsatisfied with the status of this recall,” according to an update it released Thursday and attributed to Jeff Shuren, M.D., director of the FDA’s Center for Devices and Radiological Health.

This time around, the FDA is taking issue with the independent testing Philips commissioned—on a post-recall request from the regulator—to assess the safety of the polyester-based polyurethane (PE-PUR) foam at the heart of the recall. The foam, which was added to many of Philips’ CPAP and BiPAP machines and ventilators to muffle sound and vibrations, was found to break down over time and possibly release debris and chemicals into a user’s airflow.

Philips reaches first settlement in class-action CPAP lawsuit

Since the start of the recall, the FDA has warned that inhaling particles released by the disintegrating foam could potentially lead to internal and external irritation, headaches, asthma, nausea or “toxic or carcinogenic effects to organs, such as kidneys and liver.”

Meanwhile, though Philips initially issued similar warnings, it has since changed its tune, touting instead the results of the independent testing, which concluded that exposure to materials released by the foam “is unlikely to result in an appreciable harm to health in patients.”

Is the FDA overreacting??  Many people no longer trust the FDAs judgment, since the COVID-19 mRNA EUA.  

Those findings clash with the FDA’s tally of more than 105,000 medical device reports (MDRs) related to the recalled devices that it received between April 2021 and the end of March of this year, including 385 reports of death—though both the FDA and Philips have been quick to note that MDRs are unvetted submissions and therefore their contents may not be directly linked to Philips’ devices.

Additionally, some experts have singled out the genotoxicity findings in the Philips-commissioned testing: The foam repeatedly tested positive for genotoxicity, and though the device maker said the results still fell within acceptable safety standards, experts interviewed in a recent ProPublica report argued that genotoxicity in any capacity is cause for “alarm,” since it denotes an ability to damage the genetic information within a cell, potentially leading to cancer-causing mutations.

It should be noted that genotoxicity was found in in vitro animal testing, not in a human Clinical Trial.

The FDA recall shows the inconsistency of the FDA's methodology as it approved an mRNA COVID-19 vaccine without a full approval process, yet recalled a previously approved device




FDA ‘remains unsatisfied’ with Philips’ handling of CPAP recall