Wakey, Wakey, Sleepy Head
Data from the National Health and Nutrition Examination Survey sheds light on the role of cannabis in sleep–wake regulation
Despite being prescribed for many sleep disorders – and used by countless others without a prescription – the clinical evidence for the benefits of cannabis on sleep–wake regulation has (thus far) been mixed at best and inconclusive at worst. And so a group of researchers from the University of Toronto, Canada, looked at data from the National Health and Nutrition Examination Survey from 2005–2018 to determine the relationship between cannabis use and sleep duration (1). They discovered that recent users were 34 percent more likely to report short sleep (less than 6 hours) and 56 percent more likely to report long sleep (more than 9 hours) than those who hadn’t used cannabis in the preceding 30 days. They were also 31 percent more likely to report difficulty falling asleep, staying asleep, or sleeping too much. The results showed this pattern was even stronger for “heavy” users (those using cannabis on 20 out of the 30 previous days).
As an observational study, the reasons behind the findings are hard to pinpoint – and the researchers themselves point to several limitations. To find out more, we spoke to lead author of the paper, Calvin Diep.
What are the biggest misconceptions about cannabis and sleep?
Cannabis use is on the rise across North America and Europe. The effects of cannabis and cannabinoids as potential therapeutic agents are not yet fully understood, despite popular use as adjuncts to other pain therapies or sleep aids, for example. The findings from clinical studies investigating the relationship between cannabis and sleep health are mixed or inconclusive, when considered as a whole. Why? Cannabis is not a single entity but rather a broad category of various plants/agents with varying proportions of medically active components – consider CBD to THC ratio just one such important variable. It’s difficult to compare different strains or formulations used across different studies, and the patient populations and medical indications in which clinical studies are conducted can vary greatly. Most misconceptions therefore arise from generalizations about study results without considering the specific cannabinoids used (if specified) and populations studied.
What is the key takeaway of your research – despite the limitations you’ve acknowledged?
The cross-sectional nature of the dataset used certainly needs to be considered when interpreting our findings. With this in mind, the key takeaway is that cannabis use may be associated with the extremes of sleep duration (too little or too much). Also, higher frequency of cannabis use (20 or more days per month) may put users at even greater risk of experiencing these extremes. Adequately powered randomized controlled trials are needed to say anything further about the effects of cannabis on sleep duration or architecture.
Did the results surprise you at all?
From our own clinical interactions with patients, we knew there was a lot of anecdotal evidence to suggest cannabinoids might impact sleep health. However, this has only been observed in some patients. This present study adds to a (much-needed) evidence base in support of the relationship between cannabis and derangements in sleep duration at the population level. However, to our knowledge, this is the first study to report a dose–response relationship between frequency of cannabis use and sleep duration outcomes, providing some evidence of a biologic gradient.
Are you planning further research in this area?
Cannabis research is an exciting field that continues to grow, with many potentially important applications. With cannabis and cannabinoids increasingly being used recreationally or prescribed as therapies, an evolving evidence base will be needed to inform guidelines for the clinical use of these agents in specific patient populations. Our research group continues to investigate cannabis/cannabinoid use patterns at both the patient and population level to better understand the relationships to various clinical or behavioral outcomes, such as pain, sleep outcomes, and mental health metrics.
- Diep C, et al. Reg Anesth Pain Med, 0, 1-5 (2021). DOI: 10.1136/rapm-2021-103161
By the time I finished my degree in Microbiology I had come to one conclusion – I did not want to work in a lab. Instead, I decided to move to the south of Spain to teach English. After two brilliant years, I realized that I missed science, and what I really enjoyed was communicating scientific ideas – whether that be to four-year-olds or mature professionals. On returning to England I landed a role in science writing and found it combined my passions perfectly. Now at Texere, I get to hone these skills every day by writing about the latest research in an exciting, creative way.
