SAN ANTONIO — Although one state has authorized medical cannabis as a treatment for obstructive sleep apnea (OSA), the science supporting it remains shaky and physicians should be very cautious about recommending it, a sleep medicine specialist said here.
“The evidence is starting to come in, but it is still limited,” said Kannan Ramar, MD, of the Mayo Clinic Rochester, speaking Tuesday at SLEEP 2019, the joint meeting of the American Academy of Sleep Medicine (AASM) and the Sleep Research Society.
Ramar was lead author of an official AASM position statement published last year, issued after Minnesota approved OSA as a qualifying condition for medical cannabis.
“Based on the available evidence, it is the position of the AASM that medical cannabis should not be used for the treatment of OSA,” the statement read. “The AASM also advises state legislators, regulators, and health departments that OSA should not be included as an indication for their medical cannabis programs.”
In his talk at SLEEP 2019, Ramar said the safety and efficacy of cannabis for this purpose remains unknown, despite publication of a study supporting use of a cannabis-derived drug in OSA.
Ramar noted that the clinical research considered by Minnesota officials in reaching their decision was limited to proof-of-concept, animal, and pilot studies. Human studies have examined the oral cannabis-extract drug dronabinol (Marinol) which is approved by the FDA for nausea and vomiting associated with cancer treatment.
The Pharmacotherapy of Apnea by Cannabimimetic Enhancement Trial (PACE), published in January 2018, examined dronabinol in two doses for the treatment of moderate to severe OSA in 73 patients. Patients were randomized to receive placebo 2.5 mg or 10 mg of dronabinol daily, 1 hour before bedtime. Its authors concluded that the finding of a dose-dependent reduction in apnea-hypopnea index (AHI) scores, along with greater self-reported sleepiness and treatment satisfaction among the dronabinol-treated patients “support the therapeutic potential of cannabinoids in people with OSA.”
But Ramar cited several caveats, including questionable clinical significance of the change in AHI from baseline to 6 weeks among the study participants.
He also noted that in Minnesota, where he practices, OSA patients don’t receive dronabinol since it is not approved by the FDA for this purpose. They are instead using commercially available THC or cannabidiol (CBD) products or a combination of the two through medical cannabis programs.
These products have not been studied in patients with OSA, and the safety and efficacy of specific delivery methods, including vaping and liquid formulations, is also not known, he said.
In June of last year, following the release of the AASM position statement, the Minnesota Department of Health issued a clarification of its stance on the use of cannabis for the treatment of OSA, urging patients to try other treatments known to be effective, such as CPAP, “before trying medical cannabis for OSA.”
“Very little research has been done on which medical cannabis products — if any — are effective for treating OSA,” the statement read, adding that patients who choose to “experiment” with cannabis as a treatment for OSA should first consult with their health care provider.
Kannan Ramar reported no relationships with industry related to his presentation at SLEEP 2019.