In a recent study published in Psychiatry Research, researchers examined the associations between cannabis use and sleep disturbances.
Background
Emerging adulthood is characterized by a high frequency of sleep disturbances. Studies have reported that poor sleep quality is common among students. This is even more concerning given the detrimental effects of sleep changes on physical/mental health and cognitive capacities. Moreover, the coronavirus disease 2019 (COVID-19) crisis has further exacerbated sleep concerns.
Although using cannabis is illegal in France, it is common among young people. While decriminalization/legalization of cannabis has been debated for decades, the high level of consumption among youth is alarming and could result in poor health outcomes lingering through adulthood.
About the study
The present study evaluated the associations between sleep disturbances and cannabis use. It was a cross-sectional analysis of an observational cohort (iShare) of French-speaking students from higher educational institutes and universities in France. Information on sociodemographic characteristics, lifestyle habits, and health status was obtained at baseline and through follow-up questionnaires.
The team investigated whether participants had insomnia, excessive daytime sleepiness (EDS), sleep deprivation, or poor sleep quality in the past three months. Participants were asked to indicate cannabis use in the past year. Responses were stratified into daily, weekly (one to six days a week), monthly (up to thrice a month), and rarely/never (less than once a month).
Sociodemographic characteristics, health behaviors, and prior mental health diagnoses were included as covariates. Multivariable logistic regression was applied to evaluate the relationship between cannabis use and sleep complaints. Stratified analyses were also performed to ascertain whether the association was persistent between students with and without prior mental health diagnoses.
Findings
The final analytic sample comprised 14,787 participants with an average age of 20.4 years. Most subjects were females (75.5%); 39% were first-year students, and 23% were attending health studies. Nearly 14% and 12% of participants had a history of anxiety and depression, respectively. Daily, weekly, and monthly use of cannabis were self-reported by 1.5%, 4.4%, and 20.5% of students, respectively.
Weekly/daily cannabis use was more frequent among males and those who smoked more than 10 times/day, drank > thrice a week, used sleeping drugs, or had poor economic status. Additionally, students who had anxiety/depression used more cannabis. Insomnia was self-reported by 22.7% of students. It was more common among females and those reporting poor economic status, using sleeping drugs, and smoking more than 10 times per day.
Age was not associated with the use of cannabis, and sex and age were not associated with insomnia. The prevalence of insomnia increased with the frequency of cannabis use, viz., from 22.3% in those who never/rarely used cannabis to 41% among daily users. Moreover, a higher frequency of using cannabis was associated with elevated odds of having insomnia.
Daily/weekly cannabis use was associated with insomnia after adjusting for sociodemographic characteristics and health behaviors. The findings were similar for EDS, sleep deprivation, and poor sleep quality. Insomnia was more common among cannabis users, irrespective of their history of anxiety or depression.
Daily cannabis use was higher among students with a history of depression/anxiety than those who never/rarely used cannabis. There were no significant differences in the association between insomnia and cannabis use in stratified analyses. Likewise, stratified analyses for other sleep complaints were comparable.
Conclusions
To summarize, the team noted that the odds of having insomnia increased by 45% in cannabis users than in non-users. These estimates increased with the frequency of cannabis use and were two-fold higher in daily users than those never/rarely using cannabis. EDS, sleep deprivation, and poor sleep quality were similarly associated with cannabis use.
The findings revealed that students with a historical diagnosis of depression/anxiety had elevated rates of cannabis use and sleep complaints than those without. Stratified analyses indicated that sleep complaints were more frequent in cannabis users regardless of their history of mental health diagnoses. Nonetheless, the estimates were much higher in those with a history of mental health diagnoses.
Notably, the study partially implemented a snowball recruitment method, and voluntary participation limited the representativeness. Moreover, female students over-represented the sample and exhibited lower cannabis use and more frequent sleep complaints. Therefore, caution must be exercised while interpreting the findings.