Why is the Endocannabinoid System Key to Understanding Sleep and its Disorders?
The critical role of the Endocannabinoid System (ECS) in regulating sleep cycles places it at the forefront of understanding sleep and its disorders. This complex system is deeply intertwined with various biological processes that significantly influence our sleep patterns.
At the heart of understanding sleep lies the ECS’s influence on the brain areas responsible for the sleep-wake cycle, notably the suprachiasmatic nuclei, pons, and basal forebrain. These regions are rich in cannabinoid receptors, which are directly influenced by the consumption of cannabis and its derivatives. Research exploring these interactions has revealed diverse effects on sleep, emphasizing the importance of the ECS in sleep regulation.
Sleep itself is a state of altered consciousness, characterized by decreased muscle and sensory activity. It’s during this state that the body’s systems, particularly the ECS, undergo crucial changes. The release of neurotransmitters like GABA during sleep fosters relaxation and drowsiness, highlighting the body’s intricate biological rhythm.
The implications of sleep extend far beyond mere rest. Adequate sleep contributes to memory consolidation, immune system strength, hormonal balance, and muscle regeneration, all hallmarks of good health. On the other hand, disturbed sleep patterns can lead to various health issues, including:
- Insomnia
- PTSD-related nightmares
- Respiratory disorders
- Restless leg syndrome (RLS)
- Rapid eye movement (REM) behavior disorders
Understanding the ECS’s role in sleep is not just about unraveling the science behind sleep patterns. It’s about unlocking potential treatments for sleep disorders and improving overall sleep health, particularly in the context of cannabis consumption. As research in this area evolves, the ECS could hold the key to a deeper understanding of sleep and its complexities.
Cannabis as a Treatment For Sleep Disorders
Cannabis shows promise in treating a range of sleep disorders. Researchers and healthcare practitioners are actively exploring its beneficial effects in real-world treatments, particularly in four key areas of sleep-related issues:
- Insomnia
Cannabis shows clear effectiveness in treating insomnia, with results varying based on the dose and specific cannabinoid content. For instance, in patients suffering from insomnia caused by Fibromyalgia, a synthetic THC compound called Nabilone significantly improves sleep quality and reduces insomnia’s severity.
Ongoing studies, like the CANSLEEP trial using ETC120 oil, are crucial in understanding how combinations of THC and CBD can be optimized for sleep disorder treatment. These trials help paint a clearer picture of how these compounds interact with sleep patterns.
- PTSD-related nightmares
Nightmares associated with PTSD present significant treatment challenges due to their complex nature. Standard treatments like prazosin often struggle to deliver consistent results.
Recent studies reveal that formulations including Nabilone, isolated THC, and CBD significantly reduce both the frequency and intensity of PTSD-related nightmares. These substances target the endocannabinoid system within brain areas linked to fear and emotions, such as the limbic and paralimbic systems.
- Respiratory disorders
The effects of cannabis on respiratory sleep disorders like Obstructive Sleep Apnea (OSA) are still being explored. Research suggests that cannabis-based therapies may be helpful for OSA. These include small clinical trials and animal studies, such as one involving Dronabinol, an FDA-approved THC-based medication.
- Restless Leg Syndrome (RLS)
The effectiveness of cannabis in treating RLS remains uncertain. Current evidence doesn’t strongly support its use, making it a less recommended option for RLS treatment.
- OSA
Obstructive sleep apnea (OSA) poses a persistent challenge in clinical practice, characterized by recurrent airway obstructions during sleep. With limited effective pharmacological interventions available, exploring alternative treatments is paramount.
Recent investigations have examined the potential of cannabinoids, particularly in the context of OSA. Studies have underscored the role of endocannabinoids, such as oleoylethanolamide (OEA), in modulating sleep patterns, suggesting a neuroprotective function against OSA-related complications.
In a study by Veitch et al., the impact of cannabis use on OSA severity and sleep quality was rigorously examined. Despite findings indicating no direct association between cannabis intake and reduced OSA severity, intriguing observations surfaced. Cannabis consumption correlated with an increased percentage of N3 stage sleep, implying a potential role in enhancing deep sleep phases.
Notably, in patients with moderate to severe OSA, cannabis utilization was linked to ameliorated OSA severity during REM sleep, indicating a positive influence on respiratory physiology. While further research is warranted to elucidate the mechanisms underlying these effects, these findings underscore the potential of cannabinoids as adjunctive therapies in managing OSA, offering hope for individuals grappling with this debilitating sleep disorder.
THC or CBD To Get a Better Sleep?
The two main cannabis components studied for their role in sleep are THC and CBD. Previous studies have shown that THC and CBD have different effects on sleep. In low doses, THC has been shown to promote better sleep while chronic and high doses usage can hinder sleep quality.
Some effects of short-term consumption of THC on sleep include:
- Increased sleep consolidation
- Increased total sleep time
- Increased slow-wave sleep. This is the deepest phase of NREM (Non-Rapid Eye Movement) sleep, where some dreaming and sleepwalking occur.
- Reduced sleep onset latency, which in other words means the amount of time it takes to fall asleep.
- Decreased wake after sleep onset. This parameter is the amount of time a person stays up after falling asleep.
- Decreased REM sleep, which is the phase of sleep where dreaming commonly occurs.
The effects of chronic/long-term consumption of THC on sleep:
- Reduced total sleep time
- Decreased slow-wave sleep
- Increased sleep onset latency
- Increased wake after sleep onset
- Inconsistent REM behavior
Conversely to the study of the effects of THC on sleep, the effect of CBD and other cannabinoids on sleep remains unexplored. At most, researchers have studied the effect of CBD-dominant cannabis strains; however, the results are mixed.
It does seem that consumption of CBD dominant cannabis strains decreases REM latency (the amount of time it takes to enter REM sleep) and increases TST at lower doses; yet, these outcomes might be the result of small quantities of THC within the strain.
What Happens to My Dreams When Consuming Cannabis?
One of the most prevalent and commonly self-assessed observations after stopping cannabis consumption is the vividness of the dream state. While the explanation of why this occurs remains unknown, scientists theorize that it is correlated with the alteration of REM sleep. Let’s remember that this is the sleep stage where dreaming commonly occurs. Cannabis users have been shown to undergo a reduction in their REM sleep. Yet, once they cease cannabis consumption they stop suppressing REM sleep. As a result, REM sleep starts an overcompensation process as a consequence of being inhibited for several nights. Thus, causing long vivid dreams as a consequence of the withdrawal.
Furthermore, sleep experts agree that REM sleep reduces tiredness and increases executive functioning (e.g., attention, working memory, inhibitory control, and cognitive flexibility). Therefore, chronic cannabis consumption might have a negative outcome on the overall life quality of an individual as it might decrease REM sleep.
Lastly, it is also hypothesized that anxiety and memory are related to dreaming content and recall, and they may mediate interactions between Cannabis use and dreaming. Cannabis consumption has been shown to affect both anxiety and memory, thus, it is possible that it also affects dreaming.
What Do The Latest Findings Tell Us?
An unpublished study led by Dr. Ceri Bradshaw from the University Medical School in Wales is currently undergoing clinical trials where subjects are given a portable sleep acquisition system to study their sleep patterns after smoking cannabis. This system measures their brain activity and other physiological behaviors (e.g. eye movement and heartbeat rate) through EEG (electroencephalogram) and EOG (electrooculography) while participants are asleep at home. Notably, this is the first research project to study sleep at the subject’s home, regulate the cannabis route of administration (joints), and utilize light and unobtrusive devices.
So far, they’ve discovered no significant differences between cannabis users and non-users in:
- TST
- SOL
- WASO
- Sleep quality
- Anxiety levels
- Everyday memory functioning
- Dream recall
- Length of dreams
- Vividness of dreams
On the other hand, they found that cannabis users took longer to enter REM sleep and had less amount of overall REM sleep compared to non-users. Additionally, they found that cannabis users reported significantly more life problems and bizarreness of dreams compared to non-users.
Why Aren’t Sleep Studies Faultless?
Given the complex nature of sleep, it’s been difficult to obtain consistent results among studies. One of the reasons for inconsistent results has to do with the inability to create and replicate experimental settings. Subjects of these studies have to undergo sleep studies while wearing uncomfortable instruments full of electrodes and wires (e.g. EEG and polysomnography).
In some cases, the subjects have to withstand loud noises and either bright or dim lights to complete these sleeping studies. Either way, these devices impede the replication of a natural setting for the subjects to obtain a sufficient sleep quality, thus, impeding accurate results from the experiments. Lastly, most of the experiments consist of a small sample size which limits the generalization of the results seen in the studies.
How To Construct Better Sleep Studies
To build better studies, researchers need to:
- Implement Consistent Methodologies
- Specific route of administration (inhaled, oral, ingested, and topical)
- A specific type of cannabis-based product (joint, vaporizer, blunt, bong, pipes, etc.)
- Specific potency and dosage consumed by the user
- Consistent method of data acquisition (EEG, PSG, fMRI, etc.)
- Include Larger Sample Sizes
- Increase the number of people in the study
- Increase the diversity of people in the study (gender, age, pathology type, etc.)
- Design Experimental Setups That Mimic a Natural Sleeping Environment
- Locate the experiments at the subject’s home
- Use unobtrusive devices to acquire data
Furthermore, other cannabinoids should also be studied for the potential therapeutic effect they might have on sleep.
Remarks and Recommendations
Acute and chronic consumption of cannabis appears to affect people’s sleep architecture. One of the most notable effects cannabis has on sleep is the disturbance of REM sleep. Since REM sleep is crucial for feeling refreshed after sleep and reaching optimal levels of executive functions it is imperative to fully understand how Cannabis affects it.
People interested in using cannabis as a treatment for sleep disorders should seek advice from a sleep expert physician and a cannabis expert physician. If unable to find suitable experts, people should record their individual findings and try different cannabis strains, cannabis-based products, routes of administration, and concentrations and doses of the products until they find the best fitting outcome for a good night’s sleep.
Lastly, people interested in contributing to research on the effect of cannabis consumption on sleep can join ongoing clinical trials such as PeopleScience (peoplescience. health).
References
- Bradshaw, Ceri. “Exploring the Relationship between Cannabis … – Youtube.com.” Youtube, Swansea University Medical School, 23 Apr. 2021, https://www.youtube.com/watch?v=P-aYLEaNiIA.
- Bradshaw C, Borcsok R, Taylor M, Segust S, Ford D, Carr M. P039 REM sleep and dream reports in frequent cannabis versus non-cannabis users.
- Carr M, Borcsok R, Taylor M, Segust S, Pigeon W, Bradshaw C. 0159 Reduced REM Sleep Percent in Frequent Cannabis Versus Non-Cannabis Users. Sleep. 2020 Apr 1;43:A62-3.
- Kaul, M., Zee, P.C. & Sahni, A.S. Effects of Cannabinoids on Sleep and their Therapeutic Potential for Sleep Disorders. Neurotherapeutics 18, 217–227 (2021). https://doi.org/10.1007/s13311-021-01013-w.
- Veitch MR, Jairam S, Gurges P, Cohen E, Kendzerska T, Murray BJ, Boulos MI. Cannabinoid Use and Obstructive Sleep Apnea: A Retrospective Cohort Study. Canadian Journal of Neurological Sciences. 2024 Feb 22:1-21.
- Ried K, Tamanna T, Matthews S, Sali A. Medicinal cannabis improves sleep in adults with insomnia: a randomised double‐blind placebo‐controlled crossover study. Journal of sleep research. 2023 Jun;32(3):e13793.
