Cannabis-Based Drugs Risky for Older Patients with COPD

By Pat Anson, PNN Editor

While many senior citizens are discovering the benefits of medical cannabis in relieving pain and other health problems, a large new study suggests caution is warranted for those with chronic obstructive pulmonary disease (COPD).

Researchers at St. Michael's Hospital in Toronto say older adults with COPD who take prescription drugs made with synthetic cannabinoids were 64% more likely to die. The odds are even worse for elderly patients with COPD who take high-dose cannabinoids for the first time. New users had a 178% higher risk of being hospitalized for COPD or pneumonia and a 231% increased risk of death.

"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," says lead author Nicholas Vozoris, MD, a respiratory specialist at St. Michael's and assistant professor at the University of Toronto.

"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 favouring lower over higher cannabinoid doses, when these drugs actually do need to be used."

The study analyzed the health data of over 4,000 older adults diagnosed with COPD who took either nabilone or dronabinol, two medications made with synthetic cannabinoids that are used to treat nausea, vomiting and loss of appetite.

The findings, published in the journal Thorax, suggest that nabilone and dronabinol may cause sedation and suppress breathing in patients whose health is already compromised by COPD, a progressive lung disease that causes difficulty breathing and chronic coughing.

"Older adults with COPD represent a group that would likely be more susceptible to cannabinoid-related respiratory side-effects, since older adults less efficiently break down drugs and hence, drug effects can linger in the body for longer,” said Vozoris.

“Cannabinoids may not be any safer to use among older adults with COPD than opioids, which are also associated with a heightened risk of respiratory- related morbidity and mortality. 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.”

Cannabis and Menopause

While high doses of cannabinoids may not be appropriate for older patients with COPD, many middle-aged women are using cannabis to treat symptoms of menopause.

According to a small study being presented at the annual meeting of The North American Menopause Society, over one in four women have either used or are currently using cannabis to manage menopause symptoms.

The study involved 232 female military veterans (average age of 56) living in Northern California. Over half reported hot flashes and night sweats regularly. Twenty-seven percent said they had used marijuana to help battle menopause symptoms, while another 10% said they were interested in trying cannabis.

“While the therapeutic use of cannabis by veterans is not altogether uncommon, this study is among the first to highlight veterans’ use of marijuana for this particular condition. Given cannabis’ relatively high rate of use among the women in this cohort, scientists and others would be well-advised to further explore its safety, efficacy, and prevalence among women experiencing menopause,” said Paul Armentano, Deputy Director of NORML, a marijuana advocacy group.

A 2018 survey of over 2,700 elderly patients in Israel found that medical marijuana significantly reduced their chronic pain without adverse effects. Nearly one in five patients stopped using opioid medication or reduced their dose.

Study Finds Cannabis Increases Pain Tolerance

By Steve Weakley

Medical marijuana is often touted as a promising new form of pain relief.  But a new study found that cannabinoids may not reduce pain as much as they increase our tolerance of pain and make it less unpleasant.

Researchers at Syracuse University conducted a systematic review of 18 placebo-controlled studies involving nearly 450 participants who used a wide variety of cannabis products, including plant-based marijuana and two synthetic marijuana-based drugs, dronabinol and nabilone.

Because most previous cannabis studies have only examined patients with chronic pain, which is often associated with depression, anxiety and other symptoms that could bias results, the researchers only selected studies that used healthy individuals and laboratory tests that induced “experimental” pain.  

They reported in the journal JAMA Psychiatry that cannabinoids did not reduce pain intensity, but made the experimental pain “feel less unpleasant and more tolerable.”

"If you think of pain as a noxious sound coming from a radio, the volume is the intensity of that pain," researcher Martin De Vita told MedPage Today. "After using cannabinoid drugs, it may not decrease the volume of the noxious noise, but it may tune it to a station that's a little less unpleasant. It won't be the most beautiful music you've ever heard -- it will still be pain -- but it will be a little less unpleasant.”

Researchers found that relatively high cannabinoid dosages improved pain tolerance, but low doses had little or no effect.  The plant-based marijuana was also more effective at reducing pain than the synthetic pharmaceuticals drugs, which are primarily used to prevent nausea.

De Vita says findings from the 18 placebo-controlled studies are somewhat compromised because patients getting the plant-based cannabis “felt high,” while those getting placebo did not. He said future studies need to test non-psychoactive cannabinoids like cannabidiol, which do not have tetrahydrocannabinol (THC), the substance in marijuana that causes euphoria.

"Everyone is saying we need more research and that we need to catch up," De Vita said. "This is a first step in doing that, starting from the fundamentals of how cannabinoids affect basic pain processes, and now we need to determine some of these follow-up questions." 

This is not the first study to get mixed results on the effectiveness of cannabis in treating pain. A recent Australian study of over 1,500 adults with chronic pain, published in The Lancet Public Health, found "no evidence that cannabis use improved patient outcomes.”

But a 2017 report by the National Academies of Sciences (NAS) found “substantial evidence” that cannabis is an effective treatment for chronic pain. The NAS found that “cannabinoids demonstrate a modest effect on pain.”