Obstructive sleep apnea or OSA has been described as one of the more serious yet least recognized health risks to American adults. This condition causes frequent interruptions in sleep patterns that can result in a wide range of health problems, and there are indications that OSA is becoming increasingly common among adults in the United States and across the world. While not conclusive, there is some evidence to suggest that components of marijuana may ease the severity of this condition when administered in appropriate doses and combinations.
What Is OSA?
Obstructive sleep apnea isn’t the same thing as snoring. Snoring is caused by the movement of air across soft tissues in the throat as a person inhales and exhales during sleep. And while it can be quite annoying to a bedmate, snoring in and of itself is not a significant health risk. By contrast, OSA involves a cessation of breathing known as an apnea event, which is caused by the collapse of the soft tissues in the throat that results in a partial or complete blockage of the airway.
When breathing stops during an apnea event, the body’s oxygen levels plummet. As the sleeper’s central nervous system detects this drop, it subconsciously reacts by activating what is commonly known as the “fight or flight” response, releasing adrenaline and other hormones that jolt the sleeper into a temporary moment of awakening as they gasp for air. Because this reaction takes place in a matter of seconds, the brief period of wakefulness does not register with the sleeper, who remains unaware of the pattern. In more serious cases, OSA can result in hundreds of these momentary interruptions each night.
Obstructive sleep apnea is diagnosed and quantified during a sleep study in which the patient’s breathing patterns, blood oxygen levels, and other variables are monitored and recorded. Results based on the number of times a subject stops breathing each hour are reported numerically according to a system known as the apnea-hypopnea index (AHI).
* Less than five apnea incidents per hour is considered normal sleep.
* Five to 15 apnea incidents per hour is considered mild sleep apnea.
* Fifteen to 30 apnea incidents per hour is considered moderate sleep apnea.
* More than 30 apnea events per hour is considered severe sleep apnea.
The consequences of untreated OSA go beyond simply feeling tired and unable to focus in the daytime. If left untreated, the stresses OSA places on the body can lead to a wide range of health issues from hypertension and heart disease to depression, weight gain, brain damage, metabolic syndrome, and an increased risk of developing type 2 diabetes and certain cancers.
Determining the actual prevalence of OSA among American adults is complicated by the large number of cases that go unrecognized and undiagnosed. The medical community has traditionally reported estimates that anywhere from 5% to more than 10% of adults suffer from this condition. However, more recent studies have shown a rise in cases over the past two decades, and the American Academy of Sleep Medicine now estimates that 26% of adults between the ages of 30 and 70 years suffer from sleep apnea.
Current Treatments For OSA
The problem of interrupted sleep has long been recognized by the bedmates of those who suffer from this condition, but it wasn’t until 1965 that OSA was first mentioned in medical literature, and more than 15 years after that when the first effective treatment option was developed in the form of the Continuous Positive Airway Pressure or CPAP machine. These devices are essentially air pumps that are used in conjunction with a face mask to supply the wearer with a steady flow of air during the night to keep the airway from collapsing. But while CPAP therapy can be effective, a significant number of OSA sufferers cannot tolerate wearing the equipment and soon discontinue use.
More recently, a second form of sleep apnea therapy has emerged from the dental community in the form of oral appliances that force the sleeper’s jaw to remain in a forward position that maintains an open airway. These appliances face similar problems as CPAP therapy, as many users find them uncomfortable, and their use may also create issues such as TMJ and tooth movement.
Marijuana As A Potential Therapy For OSA
Both anecdotal evidence and clinical reporting suggest that a moderate quantity of inhaled marijuana may reduce sensations of depression, anxiety, stress, and insomnia. Additionally, the administration of CBD has been shown to improve sleep scores in clinical settings. Such findings suggest that at the very least marijuana might be considered as a sleep aid for OSA patients who have difficulty falling asleep while using CPAP or other conventional therapies.
There is also limited evidence that certain cannabinoids found within marijuana may reduce the severity and frequency of actual sleep apnea incidents. One of the first such indications comes from a 2002 study in which laboratory rats and bulldogs were administered varying doses of THC and monitored for sleep apnea events. The authors reported that THC decreased the frequency of apnea events by 42% during non-REM sleep, and 58% during REM sleep cycles.
This led scientists to report that:
This study demonstrates potent suppression of sleep-related apnea by both exogenous and endogenous cannabinoids. These findings are of relevance to the pathogenesis and pharmacological treatment of sleep-related breathing disorders.
A similar animal-based study published a decade later found that administration of a synthetic form of THC known as dronabinol stabilized respiratory patterns during sleep, and also enhanced muscle tone in the upper airway, which resulted in a lower incidence of airway collapse. Based on this evidence, the authors stated:
These findings underscore a therapeutic potential of dronabinol for the treatment of obstructive sleep apnea.
Synthetic THC has shown similar promise for suppressing apnea events in humans.
In a study performed at the University of Illinois at Chicago, 17 adults diagnosed with moderate to severe sleep apnea (AHI scores greater than 15/more than 15 stoppages of breathing per hour) were provided with synthetic THC before sleep. Over the course of the 21-day study, 15 of the 17 patients showed marked reductions in their AHI scores.
In summary remarks, the researchers stated:
This pilot study supports the safety and tolerability of dronabinol in patients with OSA. Dronabinol resulted in a significant improvement in AHI compared to baseline, with an overall reduction by 32 percent, a response that if replicated, may be significant in mild-moderate OSA.
And suggested that:
Dronabinol treatment may be a viable alternative or adjunctive therapy in selected patients with OSA.
More recently, a 2018 clinical trial of 73 individuals diagnosed with moderate to severe sleep apnea were provided with synthetic THC in dosages of either 2.5 or 10mg. Subjects in both groups recorded significant reductions in AHI scores. At the onset of the study, the group average AHI score was around 25. Administration of synthetic THC prior to sleep dropped this score by an average of 10 to 12 incidents per hour.
THC And Serotonin
The exact mechanisms that potentially link marijuana use to a measured decrease in frequency and severity of sleep apnea events have not been fully identified. One connection that has emerged is the role cannabis can play in the regulation of serotonin levels, which in turn play a role in apnea events. A 2017 review of literature focused on the relationships of cannabis, cannabinoids, and sleep noted:
Novel studies investigating cannabinoids and obstructive sleep apnea suggest that synthetic cannabinoids such as nabilone and dronabinol [two forms of synthetic THC] may have short-term benefit for sleep apnea due to their modulatory effects on serotonin-mediated apneas.
The same review also concluded that:
CBD may hold promise for REM sleep behavior disorder and excessive daytime sleepiness.
This second finding may be of interest to OSA sufferers, even though it does not indicate that CBD plays a role in the reduction of apnea events. Daytime sleepiness is a major concern for OSA sufferers, as it can lead to lost productivity and unsafe practices such as nodding off while driving.
The role of serotonin in sleep apnea events has been documented in a number of studies, and it is understood that reductions in serotonin production during sleep can cause a relaxation of muscles of the upper airway, resulting in a narrowing and possible collapse of the airway. A study published in the journal Sleep in 2017 looked at 98 individuals diagnosed with OSA to determine if the severity and frequency of apnea events were lessened when serotonin uptake during sleep. The study suggested that drugs and other agents that boosted serotonin levels might prove beneficial in treating OSA.
The authors of the 2002 study cited earlier noted that:
Delta-9-THC blocked serotonin-induced exacerbation of sleep apnea, suggesting that inhibitory coupling between cannabinoids and serotonin receptors in the peripheral nervous system may act on apnea expression.
But while such recommendations might seem like a green light for OSA sufferers to engage in pre-sleep cannabis therapies, the relationship between marijuana and restful sleep induced by boosting serotonin levels is more complex, and appears to be dosage-dependent. A 2007 study from McGill University concluded that a synthetic form of THC administered to animal subjects resulted in an increase in serotonin levels, while the administration of high doses of the same compound caused serotonin levels to drop below that of animals that were not administered THC.
This led researchers to report that:
[The results] actually demonstrated a double effect: At low doses [synthetic THC] increases serotonin, but at higher doses the effect is devastating, completely reversed.
As new research on THC’s potential therapeutic benefits for the treatment of OSA emerges, CannaMD will continue to provide updates!