Oral Cannabinoids Linked to Higher Mortality Risk in Older COPD Patients, Study Finds

Older patients with chronic obstructive pulmonary disease (COPD) taking oral, synthetically-made cannabinoids — medications based on compounds found naturally in marijuana (the plant Cannabis sativa) — to manage some of their symptoms have a 64% higher risk of death compared to those not taking the medications, according to a recent study.

The study also found that patients taking higher doses of cannabinoids have an increased risk of being hospitalized for COPD or pneumonia, and of dying from any cause, compared to those not using the medications.

These findings have important implications, according to investigators, because prescriptions of oral cannabinoids have been increasing steadily among COPD patients in recent years.

The study reporting the findings, “Morbidity and mortality associated with prescription cannabinoid drug use in COPD,” was published in the journal Thorax.

“Cannabinoid drugs are being increasingly used by older adults with COPD, so it is important for patients and physicians to have a clear understanding of the side-effect profile of these drugs,” Nicholas Vozoris, MD, said in a press release. Vozoris is a respirologist at St. Michael’s Hospital of Unity Health Toronto, Canada, and lead author of the study.

“Our study results do not mean that cannabinoid drugs should be never used among older adults with COPD. Rather, our findings should be incorporated by patients and physicians into prescribing decision-making. Our results also highlight the importance of favoring lower over higher cannabinoid doses, when these drugs actually do need to be used,” said Vozoris, who also is an associate scientist at the hospital’s Li Ka Shing Knowledge Institute.

The use of oral cannabinoids, such as nabilone and dronabinol, has been increasing among older COPD patients as a way to treat some chronic conditions that these patients usually develop, including muscle pain, insomnia, and shortness of breath.

“However, there is little evidence to support using cannabinoids for these purposes among individuals with COPD,” investigators wrote.

Moreover, their sedative and muscle relaxant properties may have several negative effects in COPD patients, including increasing the risk of pulmonary aspiration (inhalation of foreign substances) and making breathing even more difficult.

Despite these facts, “there are no published studies on prescription cannabinoid drug use and clinically meaningful health outcomes among individuals with COPD,” the researchers wrote.

Now, researchers in Canada have reported the findings of a population-based study exploring the possible relationship between cannabinoid use and negative clinical outcomes in COPD patients age 66 and older.

To that end, the team reviewed and compared clinical data from a group of 2,106 COPD patients who had been recently prescribed nabilone or dronabinol, to another group of 2,106 patients who received a prescription for a non-cannabinoid medication (control group).

All information was collected from health administrative data pertaining to people living in Ontario from April 2006 to October 2016, which was provided by ICES.

Although patients who started taking cannabinoids did not have a higher risk of being hospitalized or visiting the emergency department for COPD or pneumonia, they were found to have a 64% increased relative risk of death compared to those who were not taking these medications.

Analyses also found that those taking higher doses of either nabilone or dronabinol — more than 1.5 mg per day — had a 178% higher relative risk of being hospitalized for COPD or pneumonia, compared to those taking non-cannabinoid medications.

In addition, patients taking higher doses of cannabinoids also were found to have a 231% increased relative risk of all-cause mortality, compared to controls.

An additional analysis focused on comparing the effects of cannabinoids to opioids, as cannabinoids often are prescribed as an alternative to them. Opioids are another class of medications prescribed to manage chronic pain, but they have been linked to an increased risk of respiratory-related morbidity and mortality.

No evidence was found supporting the claim that cannabinoids may be a safer option than opioids to help older COPD patients manage their symptoms.

“In conclusion, among older adults with COPD, new cannabinoid drug use was associated with significantly increased rates of hospitalisation for COPD or pneumonia among those receiving higher doses, and increased rates of all-cause mortality, regardless of cannabinoid dose,” investigators wrote.

“While further research is needed to confirm the safety profile of cannabinoid drugs among older adults with COPD, our findings should be taken into consideration in prescribing decision making in this population,” the team concluded.