Data derived from medical cannabis patients being treated for insomnia show that cannabis could be an effective treatment for the disorder that affects the sleep of approximately 10% of people living in the UK.
The study, published in the journal Brain and Behavior, assessed clinical outcomes that were self-reported by patients who were being prescribed cannabis-based medicinal products (CBMPs) via a UK-based clinic. Researchers used the data to determine how CBMPs affect insomnia, anxiety, and general health-related quality of life. The data used was drawn from the UK Medical Cannabis Registry, a ‘comprehensive, prospective registry designed to collate outcomes on medical cannabis prescribing’.
61 participants completed standardised assessments to measure their sleep quality (SQS), anxiety levels (GAD-7), and how health affects their general quality of life (EQ-5D-5L). Answers were used to establish a baseline for researchers to measure against results that were recorded at 1 month, 3 months and 6 months after the initial assessment. 24 patients in this study were prescribed cannabis flower for use with a dry herb vaporiser, 16 patients were prescribed oils, and 17 patients were prescribed both flower and oil.
The results show improvements in patients’ sleep at all three follow-up assessments, as well as improvements at all follow-up assessments in anxiety levels, and health-based quality of life. A small number of respondents reported adverse effects from using CBMPs; 13% reported symptoms including dry mouth, dizziness, and insomnia. No life-threatening events were reported.
“This case series investigated an insomnia patient cohort treated with CBMPs. There was an improvement in subjective sleep quality as evidenced by the large effect size seen in change in SQS score,” study authors reported. “More than 40% of participants who completed each PROM [patient-reported outcome measures] round reported clinically significant improvement in their sleep quality at each time period. These results show that initiation of CBMP therapy was associated with improvements in those patients who had previously failed to respond to currently licensed treatments for insomnia. Improvements in GAD-7, SQS, and EQ-5D-5L Index values at 1, 3, and 6 months (p < .050) were witnessed after CBMP commencement. EQ-5D-5L subscores for usual activity, pain and discomfort, and anxiety and depression also improved at 1 and 3 months (p < .050).”
The study has several limitations which means further research must be completed before firm conclusions can be made on how CBMPs can reduce insomnia symptoms in those who live with it. Researchers hope more data will be produced as the number of patients being prescribed cannabis in the United Kingdom increases.
“As a case series, without control or randomization, it is not possible to conclude that CBMPs were solely responsible for the changes in sleep-specific outcomes and general HRQoL. In addition to this, the study is subject to a sampling bias, with many participants reporting prior cannabis use at study baseline. While the present study has high external validity, significant clinical heterogeneity remains. Due to the present size of the insomnia cohort within the UKMCR at the time of this analysis there was insufficient data to conduct specific subanalyses according to specific patient or product characteristics. In the future as the size of the UK Medical Cannabis Registry continues to grow assessments of the effects seen in individuals prescribed specific CBMPs or in those naïve to cannabis should be explored.”
“This novel case series assessed patients suffering from insomnia prescribed CBMPs for up to 6 months, showing an associated improvement in self-reported sleep quality, generalized anxiety and general HRQoL. While approximately 40% or more individuals experienced a clinically significant improvement in sleep quality, it is important to recognize that these findings must be interpreted within the limitations of the study design. Ultimately, RCTs will be necessary to determine the true efficacy of CBMPs for insomnia. Moreover, longer-term analyses will be required to determine whether there is an effect of tolerance on CBMP efficacy in insomnia. However, the results do suggest that CBMPs are largely well tolerated by most individuals within 6 months of follow-up,” the study concluded.
