CADTH Health Technology Review
Nabilone for the Treatment of Posttraumatic Stress Disorder: A 2023 Update
Rapid Review
Authors: Calvin Young, Danielle MacDougall, Angie Hamson
Abbreviations
PTSD
posttraumatic stress disorder
RCT
randomized controlled trial
Key Messages
One relevant systematic review of high methodological quality did not include any randomized controlled trials (RCTs) on the effectiveness of nabilone for the treatment of posttraumatic stress disorder (PTSD).
We did not find any evidence-based guidelines on the use of nabilone for adults with PTSD.
Context and Policy Issues
PTSD is a chronic psychiatric disorder that can develop in individuals who have experienced or witnessed a traumatic event or series of events, such as natural disasters, war or combat, motor vehicle accidents, or other exposures to actual or threatened death, serious injury, or sexual violence.1,2 Common symptoms of PTSD include intrusive thoughts, nightmares, flashbacks, dissociation, feelings of sadness or guilt, and intense distress at real or symbolic reminders of the trauma.3 People with PTSD can be at higher risk for other mental health conditions, including depression, substance use disorders, anxiety disorders, and sleep disorders.1,4,5 PTSD and these common comorbidities are associated with decreased quality of life and function, disability, and increased mortality.6-10
Research suggests that approximately 9.2% of people in Canada will have PTSD at some point in their lives.11 This rate is higher in women and in occupational groups who are at increased risk of experiencing traumatic events, such as health care workers, first responders, and correctional workers.11-14
Treatment strategies for managing PTSD include pharmacotherapy, psychotherapy (e.g., cognitive behavioural therapy), or other nonpharmacological interventions (e.g., exercise).15 Selective serotonin reuptake inhibitors (e.g., paroxetine, fluoxetine, sertraline) and serotonin and norepinephrine reuptake inhibitors (e.g., venlafaxine) are often recommended as first-line pharmacological interventions for PTSD.16 In recent years, there has been growing interest in studying the potential role of cannabinoids for the treatment of PTSD.17-19 Cannabinoids are a class of biological compounds that bind to cannabinoid receptors, which are involved in multiple intracellular signal transduction pathways implicated in regulating various physiologic and cognitive processes.20-22 Many cannabinoids are derived naturally from plants of the Cannabis genus, but they can also be synthetically produced.23 Nabilone is a synthetic cannabinoid that is chemically similar to tetrahydrocannabinol, the primary psychoactive component of cannabis. Originally approved for treating chemotherapy-induced nausea and vomiting, it has been proposed as a possible therapeutic option for the management of PTSD due to its route of administration (i.e., oral) and pharmacokinetic properties.24,25
CADTH has previously reviewed literature regarding the use of nabilone for the treatment of adults with PTSD. A 2019 CADTH report26 identified 2 relevant primary studies (1 crossover RCT and 1 retrospective chart review). Within the crossover RCT, participants experienced a reduction in the frequency of nightmares while being treated with nabilone compared to when they were receiving placebo.26 Participants in the retrospective cohort study reported a statistically significant decrease in PTSD symptoms (including insomnia and nightmares) following treatment with nabilone compared with before treatment.26 In 2021, CADTH conducted an update to the 2019 report,27 in which 2 additional systematic reviews (that included a total of 1 relevant single-arm, open-label cohort study) were identified for inclusion. Findings of the single-arm, open-label cohort study suggested that some patients (72% of the study population [34 of 47]) experienced total cessation or reduction of nightmares during treatment with nabilone.27 Although these 3 primary studies suggested that treatment with nabilone may be associated with improvements in some PTSD symptoms, the available evidence was of limited quantity and had methodological limitations (e.g., lack of studies with active control groups, small sample sizes, limited generalizability to the overall PTSD population in Canada) that made it difficult to draw conclusions on the effectiveness of nabilone for the treatment of PTSD.26,27 Additionally, neither of the previous CADTH reports26,27 identified evidence-based guidelines that included recommendations regarding the use of nabilone for the treatment of PTSD.
The objective of the current report is to is to identify and summarize the clinical evidence and the evidence-based guidelines regarding the use of nabilone for the treatment of adults with PTSD published since the 2021 CADTH report27 on this topic.
Research Questions
What is the clinical effectiveness of nabilone for the treatment of posttraumatic stress disorder (PTSD) in adults?
What are the evidence-based guidelines regarding the use of nabilone for the treatment of PTSD in adults?
Methods
Literature Search Methods
The literature search strategy used in this report is an update of one developed for a previous CADTH report, run on October 20, 2021.27 For the current report, a limited literature search was conducted by an information specialist on key resources, including MEDLINE, Embase, PsycINFO, the Cochrane Database of Systematic Reviews, the International HTA Database, Canadian and major international health technology agencies, as well as a focused internet search. For the current report, database searches were rerun on January 11, 2023, to capture any English-language documents published or made available since the last completed search. No filters were applied to limit the retrieval by study type. The search of major health technology agencies was also updated to include documents published since October 2021.
Selection Criteria and Methods
One reviewer screened citations and selected studies. In the first level of screening, titles and abstracts were reviewed and potentially relevant articles were retrieved and assessed for inclusion. Because this is an update to previous CADTH reports, articles were included if they were made available since the previous search dates and not included in the 2021 or 2019 CADTH reports.26,27 The final selection of full-text articles was based on the inclusion criteria presented in Table 1. Publications that did not meet the inclusion criteria but provided information related to real-world evidence for nabilone for adults with PTSD were compiled to be included in an Appendix.
Criteria | Description |
|---|---|
Population | Adults with a diagnosis of PTSD |
Intervention | Nabilone |
Comparator | Q1: Active treatments (e.g., pharmacotherapy, psychotherapy); placebo; no treatment Q2: Not applicable |
Outcomes | Q1: Clinical effectiveness (e.g., severity of PTSD symptoms, anxiety, depression, quality of life, safety [e.g., adverse events, potential for misuse]) Q2: Recommendations regarding best practices (e.g., appropriate patient populations, recommended treatment protocols) |
Study designs | Health technology assessments, systematic reviews, randomized controlled trials, nonrandomized studies, evidence-based guidelines |
PTSD = posttraumatic stress disorder; Q = question.
Exclusion Criteria
Articles were excluded if they did not meet the selection criteria outlined in Table 1, were duplicate publications, or were included in the 2021 or 2019 CADTH reports26,27 on this topic. Systematic reviews in which all relevant studies were captured in other more recent or more comprehensive systematic reviews or in the 2021 or 2019 CADTH reports26,27 were excluded. Primary studies retrieved by the search were excluded if they were captured in 1 or more included systematic reviews. Guidelines with unclear methodologies were also excluded.
Critical Appraisal of Individual Studies
The included systematic review was critically appraised by 1 reviewer using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2)28 as a guide. Summary scores were not calculated for the included study; rather, the strengths and limitations of each included publication were described narratively.
Patient Engagement
CADTH has adopted the CADTH Framework for Patient Engagement in Health Technology Assessment,29 which includes standards for patient involvement in individual health technology assessments and is used to support and guide CADTH activities involving patients. For this report, CADTH engaged a patient contributor with lived experience of treating PTSD with nabilone.
Invitation to Participate and Consent
CADTH reached out to the PTSD Association of Canada and the Mental Health Commission of Canada. Both organizations have communities of people with lived experience of mental health conditions, including PTSD. A CADTH Patient Engagement Officer contacted the groups by email to explore their interest in becoming involved. The preliminary request included an overview of this project, the purpose of engagement, and the nature of engagement activities. An individual was identified, and the Patient Engagement Officer obtained the person’s informed consent to share their lived experiences with PTSD and nabilone with CADTH staff.
Engagement Activities
One contributor shared their personal experiences by video call during the drafting of the report. The patient’s perspectives gained through engagement processes were used to ensure the relevance of the outcomes of interest for the clinical assessment and to provide insights, background, and context to help inform the Discussion section.
The patient’s involvement was guided by the Guidance for Reporting Involvement of Patients and the Public (version 2) Short Form reporting checklist, which is outlined in Appendix 4.30
Summary of Evidence
Quantity of Research Available
A total of 38 citations were identified in the literature search. Following screening of titles and abstracts, 30 citations were excluded and 8 potentially relevant reports from the electronic search were retrieved for full-text review. Four potentially relevant publications were retrieved from the grey literature search for full-text review. Of these potentially relevant articles, 11 publications were excluded for various reasons, and 1 systematic review met the inclusion criteria and was included in this report. Appendix 1 presents the PRISMA31 flow chart of the study selection.
Additional references of potential interest that did not meet the inclusion criteria are provided in Appendix 5. No publications that provided information related to real-world evidence for nabilone for adults with PTSD were identified.
Summary of Study Characteristics
One systematic review32 met the selection criteria and was identified for inclusion in this review. No relevant health technology assessments, RCTs, nonrandomized studies, or evidence-based guidelines were identified.
The included systematic review32 had broader inclusion criteria than the present review. Specifically, the authors evaluated the clinical effectiveness of any pharmacologic or nonpharmacologic interventions for PTSD or comorbid PTSD and substance use disorder in adults, including cannabinoids. The systematic review32 was conducted as an update to 2 previous systematic reviews,33,34 and informed updates to the PTSD Trials Standardized Data Repository (a comprehensive database of PTSD trials) by the National Center for PTSD. The systematic review32 included RCTs published between June 1, 2018, and July 30, 2021 (studies published between 1980 and 2018 were eligible for the first review34 in this series of systematic reviews). In total, 437 RCTs were included in the review (48 identified in the update); however, none of the included RCTs evaluated the clinical effectiveness of nabilone.
Additional details regarding the characteristics of the included systematic review32 are provided in Appendix 2.
Summary of Critical Appraisal
The systematic review32 had clearly defined research questions and study eligibility criteria that included components of population, intervention, comparator, outcomes, and time frame for follow-up. The review methods were established before conducting the review and were made available in a published protocol. No deviations from the protocol were identified, increasing the validity of the review.32 The authors performed literature searches using multiple databases, described the search strategies in detail, including search terms and search restrictions (e.g., restrictions on publication date and language), presented a flow chart illustrating the study selection process, and provided a list of studies excluded after full-text review. These methodological strengths increase the transparency and reproducibility of the literature searches and article selection process. Article selection and data extraction were performed using at least 2 reviewers, decreasing the likelihood for inconsistencies in these processes. The review authors stated that they had no conflicts of interest related to this review and disclosed their source of funding, which was considered unlikely to have influenced the findings of the review.32
While the systematic review32 was considered to be of high methodological quality, some limitations were identified. Specifically, the review32 did not incorporate searches for grey literature and did not justify the decision to restrict study inclusion to articles published in English. As a result, there is a risk that relevant studies published outside of traditional publishing and distribution channels or in other languages were not captured.
The included systematic review32 included no primary studies relevant to the current report. Consequently, additional critical appraisal considerations outlined in the AMSTAR 2,28 such as the appropriateness of methods used for evidence synthesis and data analysis, were not assessed because they do not affect the interpretation of the evidence made in this report.
Additional details regarding the strengths and limitations of the systematic review32 are provided in Appendix 3.
Summary of Findings
Clinical Effectiveness of Nabilone for PTSD
No relevant evidence regarding the clinical effectiveness of nabilone for the treatment of PTSD in adults was identified; therefore, no summary can be provided.
Guidelines Regarding the Use of Nabilone for PTSD
No relevant evidence-based guidelines regarding the use of treat-and-release protocols for patients requiring emergency medical services were identified; therefore, no summary can be provided.
Limitations
Based on the findings of this report, there is a paucity of literature on the clinical effectiveness of nabilone for PTSD published since the 2021 CADTH review27 on this topic. In addition, the current report and the 2 previous CADTH reviews26,27 did not identify any evidence-based guidelines that provided recommendations on the use of nabilone in adults with PTSD.
Conclusions and Implications for Decision- or Policy-Making
One systematic review32 on pharmacologic and nonpharmacologic treatments for PTSD was included in this review. However, the review32 did not include any studies that examined nabilone. No evidence-based guidelines regarding the use of nabilone in patients with PTSD were identified.
Although the current report did not identify any studies that addressed the clinical effectiveness of nabilone for the treatment of adults with PTSD, previous CADTH reviews26,27 have identified and summarized evidence from 3 primary studies. These comprised 1 crossover RCT and 2 single-arm cohort studies. As summarized in the 2019 CADTH review,26 participants of the crossover RCT reported a reduction in the frequency of nightmares when treated with nabilone compared to when receiving placebo.26 Findings from the 2014 retrospective, single-arm, cohort study indicated that participants experienced a statistically significant decrease in PTSD symptomology (including insomnia and nightmares) during treatment with nabilone compared with before treatment.26 Regarding the 2009 single-arm, open-label, cohort study (which was described in the 2021 CADTH review),27 the authors suggested that some patients (72% of the study population [34 of 47]) experienced total cessation or reduction of nightmares during treatment with nabilone.27 In total, these 3 primary studies analyzed data from 161 participants.26,27 The findings from these studies should be interpreted with caution because the available evidence was of limited quantity and had methodological limitations (e.g., lack of studies with active control groups, small sample sizes, limited generalizability to the overall PTSD population in Canada).26,27
After speaking with an individual with lived experience with nabilone as a treatment for PTSD, the outcomes that were identified as important to patients included anger, aggression, anxiety, and sleep quality. Although the primary studies summarized in the previous CADTH reports evaluated the potential impact that nabilone could have on sleep-related outcomes, there appears to be little published literature on the effects of nabilone on anger, aggression, and anxiety in adults with PTSD.
Future higher-quality research examining the clinical effectiveness of nabilone for the treatment of adults with PTSD is warranted before conclusions on the potential role of nabilone can be drawn. Investigators of future trials may want to consider using outcome measures identified as important by the patient contributor involved in this review or outcome measures that do not appear to be represented in the currently available evidence (e.g., quality of life, potential for misuse). Additional studies evaluating the effects of nabilone for PTSD may encourage the development of evidence-based guidelines, which would be useful tools to inform clinicians and policy-makers involved in providing care for adults with PTSD.
References
1.Sareen J. Posttraumatic stress disorder in adults: impact, comorbidity, risk factors, and treatment. Can J Psychiatry. 2014;59(9):460-467. PubMed
2.Lancaster CL, Teeters JB, Gros DF, Back SE. Posttraumatic stress disorder: overview of evidence-based assessment and treatment. J Clin Med. 2016;5(11):105. PubMed
3.Mann SK, Marwaha R. Posttraumatic stress disorder. Treasure Island (FL): StatPearls Publishing; 2022: https://www.ncbi.nlm.nih.gov/books/NBK559129/. Accessed 2023 Jan 12.
4.Qassem T, Aly-ElGabry D, Alzarouni A, Abdel-Aziz K, Arnone D. Psychiatric co-morbidities in post-traumatic stress disorder: detailed findings from the adult psychiatric morbidity survey in the English population. Psychiatr Q. 2021;92(1):321-330. PubMed
5.Lancel M, van Marle HJF, Van Veen MM, van Schagen AM. Disturbed sleep in PTSD: thinking beyond nightmares. Front Psychiatry. 2021;12:767760. PubMed
6.Dams J, Rimane E, Steil R, Renneberg B, Rosner R, Konig HH. Health-related quality of life and costs of posttraumatic stress disorder in adolescents and young adults in Germany. Front Psychiatry. 2020;11:697. PubMed
7.Huang L, Xu X, Zhang L, et al. Post-traumatic stress disorder symptoms and quality of life of COVID-19 survivors at 6-month follow-up: a cross-sectional observational study. Front Psychiatry. 2022;12:782478. PubMed
8.Roberts AL, Kubzansky LD, Chibnik LB, Rimm EB, Koenen KC. Association of posttraumatic stress and depressive symptoms with mortality in women. JAMA Netw Open. 2020;3(12):e2027935. PubMed
9.Giesinger I, Li J, Takemoto E, Cone JE, Farfel MR, Brackbill RM. Association between posttraumatic stress disorder and mortality among responders and civilians following the September 11, 2001, disaster. JAMA Netw Open. 2020;3(2):e1920476. PubMed
10.Byers AL, Covinsky KE, Neylan TC, Yaffe K. Chronicity of posttraumatic stress disorder and risk of disability in older persons. JAMA Psychiatry. 2014;71(5):540-546. PubMed
11.Van Ameringen M, Mancini C, Patterson B, Boyle MH. Post-traumatic stress disorder in Canada. CNS Neurosci Ther. 2008;14(3):171-181. PubMed
12.Skogstad M, Skorstad M, Lie A, Conradi HS, Heir T, Weisaeth L. Work-related post-traumatic stress disorder. Occup Med (Lond). 2013;63(3):175-182. PubMed
13.Fusco N, Ricciardelli R, Jamshidi L, et al. When our work hits home: trauma and mental disorders in correctional officers and other correctional workers. Front Psychiatry. 2021;11:493391. PubMed
14.Olff M. Sex and gender differences in post-traumatic stress disorder: an update. Eur J Psychotraumatol. 2017;8(sup4): 1351204.
15.Watkins LE, Sprang KR, Rothbaum BO. Treating PTSD: a review of evidence-based psychotherapy interventions. Front Behav Neurosci. 2018;12:258. PubMed
16.Martin A, Naunton M, Kosari S, Peterson G, Thomas J, Christenson JK. Treatment guidelines for PTSD: a systematic review. J Clin Med. 2021;10(18):4175. PubMed
17.Hindocha C, Cousijn J, Rall M, Bloomfield MAP. The effectiveness of cannabinoids in the treatment of posttraumatic stress disorder (PTSD): a systematic review. J Dual Diagn. 2020;16(1):120-139. PubMed
18.Neumeister A, Normandin MD, Pietrzak RH, et al. Elevated brain cannabinoid CB1 receptor availability in post-traumatic stress disorder: a positron emission tomography study. Mol Psychiatry. 2013;18(9):1034-1040. PubMed
19.Schlag AK, O'Sullivan SE, Zafar RR, Nutt DJ. Current controversies in medical cannabis: recent developments in human clinical applications and potential therapeutics. Neuropharmacology. 2021;191:108586. PubMed
20.Sheikh NK, Dua A. Cannabinoids. Treasure Island (FL): StatPearls Publishing; 2022: https://www.ncbi.nlm.nih.gov/books/NBK556062/. Accessed 2023 Jan 12.
21.Fride E. The endocannabinoid-CB(1) receptor system in pre- and postnatal life. Eur J Pharmacol. 2004;500(1-3):289-297. PubMed
22.Zou S, Kumar U. Cannabinoid receptors and the endocannabinoid system: signaling and function in the central nervous system. Int J Mol Sci. 2018;19(3):833. PubMed
23.Cohen K, Weinstein AM. Synthetic and non-synthetic cannabinoid drugs and their adverse effects-a review from public health prospective. Front Public Health. 2018;6:162. PubMed
24.Jetly R, Heber A, Fraser G, Boisvert D. The efficacy of nabilone, a synthetic cannabinoid, in the treatment of PTSD-associated nightmares: a preliminary randomized, double-blind, placebo-controlled cross-over design study. Psychoneuroendocrinology. 2015;51:585-588. PubMed
25.Cameron C, Watson D, Robinson J. Use of a synthetic cannabinoid in a correctional population for posttraumatic stress disorder-related insomnia and nightmares, chronic pain, harm reduction, and other indications: a retrospective evaluation. J Clin Psychopharmacol. 2014;34(5):559-564. PubMed
26.Cowling T, MacDougall D. Nabilone for the treatment of post-traumatic stress disorder: a review of clinical effectiveness and guidelines. (CADTH rapid response report: summary with critical appraisal). Ottawa (ON): CADTH; 2019: https://www.cadth.ca/sites/default/files/pdf/htis/2019/RC1076_Nabilone%20for%20Post-Traumatic%20Stress%20Disorder%20Final.pdf. Accessed 2023 Jan 12.
27.Farrell K, Premji Z. Nabilone for the treatment of posttraumatic stress disorder: a 2021 update. Can J Health Technol. 2021;1(11). 10.51731/cjht.2021.206. Accessed 2023 Jan 11.
28.Shea BJ, Reeves BC, Wells G, et al. AMSTAR 2: a critical appraisal tool for systematic reviews that include randomised or non-randomised studies of healthcare interventions, or both. BMJ. 2017;358:j4008. PubMed
29.CADTH framework for patient engagement in health technology assessment. Ottawa (ON): CADTH; 2022: https://www.cadth.ca/cadth-framework-patient-engagement-health-technology-assessment. Accessed 2023 Jan 23.
30.Staniszewska S, Brett J, Simera I, et al. GRIPP2 reporting checklists: tools to improve reporting of patient and public involvement in research. BMJ. 2017;358:j3453. PubMed
31.Liberati A, Altman DG, Tetzlaff J, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. J Clin Epidemiol. 2009;62(10):e1-e34. PubMed
32.O’Neil ME, Cheney TP, Yu Y, et al. Pharmacologic and nonpharmacologic treatments for posttraumatic stress disorder: 2022 update of the PTSD-Repository evidence base. Rockville (MD): Agency for Healthcare Research and Quality; 2022: https://effectivehealthcare.ahrq.gov/sites/default/files/related_files/pharma-nonpharma-ptsd-2022-update.pdf. Accessed 2023 Jan 12.
33.O’Neil ME, Cheney TP, Hsu FC, et al. Pharmacologic and nonpharmacologic treatments for posttraumatic stress disorder: an update of the PTSD-Repository evidence base. (Comparative effectiveness review no. 235). Rockville (MD): Agency for Healthcare Research and Quality; 2020: https://effectivehealthcare.ahrq.gov/sites/default/files/pdf/cer-235-pharma-nonpharm-ptsd-update-report.pdf. Accessed 2023 Jan 12.
34.O’Neil M, McDonagh M, Hsu F, et al. Pharmacologic and nonpharmacologic treatments for posttraumatic stress disorder: Groundwork for a publicly available repository of randomized controlled trial data. (Comparative effectiveness review no. 32). Rockville (MD): Agency for Healthcare Research and Quality; 2019: https://www.ncbi.nlm.nih.gov/books/NBK541643/. Accessed 2023 Jan 12.
Appendix 1: Selection of Included Studies
Appendix 2: Characteristics of Included Publications
Note this appendix has not been copy-edited.
Table 2: Characteristics of Included Systematic Review
Study citation, country, funding source | Study design and number of primary studies included | Population characteristics | Intervention and comparator(s) | Clinical outcomes, length of follow-up |
|---|---|---|---|---|
O’Neil et al. (2022)32 US Funding source: Agency for Health care Research and Quality. | Study design: Systematic review of RCTs. The report was an update to 2 previous systematic reviews.33,34 Number of included studies: In total, 437 RCTs were included in the systematic review. None of the included RCTs were relevant to the current report. | Studies of adults (mean age ≥ 18 years old) diagnosed with PTSD by a clinician or through a patient-reported assessment tool were eligible for inclusion. | Intervention: Any pharmacological and nonpharmacologic treatments for PTSD, comorbid PTSD and SUD, or insomnia and nightmares related to PTSD. Only studies that examined nabilone were considered relevant to the current report. Comparator: Any comparator, such as alternative PTSD interventions, waitlist, minimal attention, usual care, or placebo. | Clinical outcomes:
Follow-up: Any length of follow-up was eligible. |
CAPS = Clinician-Administered PTSD Scale; PCL = PTSD Checklist; PTSD = posttraumatic stress disorder; RCT = randomized controlled trial; SUD = substance use disorder.
Appendix 3: Critical Appraisal of Included Publications
Note this appendix has not been copy-edited.
Table 3: Strengths and Limitations of the Systematic Review Using AMSTAR 228
Strengths | Limitations |
|---|---|
O’Neil et al. (2022)32 | |
|
|
AHRQ = Agency for Healthcare Research and Quality; AMSTAR 2 = A Measurement Tool to Assess systematic Reviews 2; CENTRAL = Cochrane Central Register of Controlled Trials; CINAHL = Cumulative Index to Nursing and Allied Health Literature; RCT = randomized controlled trial; RoB 2 = Risk of Bias 2.
Appendix 4: Guidance for Reporting Involvement of Patients and the Public (Version 2) Short Form Reporting Checklist
Note this appendix has not been copy-edited.
Table 4: Patient Involvement in Nabilone for the Treatment of Posttraumatic Stress Disorder
Section and topic | Item | Reported in section |
|---|---|---|
Aim | The patient contributor was involved in sharing their experiences and perspectives of nabilone as a treatment for PTSD. The purpose of the engagement was to offer a different perspective of the treatment to allow for a more nuanced understanding of the literature and to identify gaps. | Methods |
Methods | After giving informed consent, the patient contributor discussed their experiences of PTSD and of treatment with nabilone by video call with the Patient Engagement Officer and Research Officer. | Methods |
Results of engagement | The researchers were made aware of the importance of several outcomes and themes. In particular, the relevance of the research question for patients and the outcomes that mattered (such as anger, aggression, anxiety, and sleep quality) were confirmed. They also commented on the efficacy of the same dose over a long duration, identifying the lack of tolerance development. One factor to consider is the transition period when initiating treatment with nabilone. Some patients who use cannabis within their treatment regimen report not initially liking nabilone. | Conclusions and Implications for Decision- or Policy-Making |
Discussion and conclusions | Success of patient involvement in this report is related to several factors. First, the patient contributor was briefed on the objectives of the project and supported in their role. The research team was receptive to this involvement and used it in their approach to the clinical evidence. Established processes are in place, and compensation was offered for their time to participate in the project. | Conclusions and Implications for Decision- or Policy-Making |
Reflections/critical perspective | The patient contributor was highly engaged in the conversation with CADTH staff. They reported the most distressing symptoms of PTSD that nabilone addresses, benefits to the medication, their experiences of taking the medication for a significant length of time, and their overall impressions and recommendations for the medication. Limitations to our approach include the sensitivity of discussing experiences with PTSD and the risk of triggering negative emotions during or after our engagement. This risk was mitigated by ensuring the patient was aware that they could stop the conversation at any point. They were also made given a crisis telephone number they could call should they require support after our call. Another limitation of our approach is that people need reliable access to phone and internet to contribute to CADTH, which may exclude some voices. | Conclusions and Implications for Decision- or Policy-Making |
PTSD = posttraumatic stress disorder.
Appendix 5: References of Potential Interest
Real-World Evidence
No literature identified.
Systematic Reviews
Protocols
Liu JJW, Nazarov A, Easterbrook B, et al. Four decades of military posttraumatic stress: protocol for a meta-analysis and systematic review of treatment approaches and efficacy. JMIR Res Protoc. 2021;10(10):e33151. PubMed
Review Articles
Legare CA, Raup-Konsavage WM, Vrana KE. Therapeutic potential of cannabis, cannabidiol, and cannabinoid-based pharmaceuticals. Pharmacology. 2022;107(3-4):131-149. PubMed
Scherma M, Muntoni AL, Riedel G, Fratta W, Fadda P. Cannabinoids and their therapeutic applications in mental disorders. Dialogues Clin Neurosci. 2020 09;22(3):271-279. PubMed
Stack SK, Wheate NJ, Schubert EA. Medicinal cannabis for the treatment of anxiety disorders: a narrative review. Curr Treat Options Psychiatry. 2022;9(3):163-173.
Acknowledgement: Many thanks to the anonymous patient contributor for their time and energy sharing their lived experience with posttraumatic stress disorder and with using nabilone as a part of their treatment regimen. Their contributions were invaluable.
ISSN: 2563-6596
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