The changing landscape of the use of medical marijuana after traumatic brain injury: a narrative review

The Influence of Cannabinoids on Drosophila Behaviors, Longevity, and Traumatic Injury Responses of the Adult Nervous System

Introduction: The legalization of cannabis products has increased their usage in the United States. Among the ∼500 active compounds, this is especially true for cannabidiol (CBD)-based products, which are being used to treat a range of ailments. Research is ongoing regarding the safety, therapeutic potential, and molecular mechanism of cannabinoids. Drosophila (fruit flies) are widely used to model a range of factors that impact neural aging, stress responses, and longevity. Materials and Methods: Adult wild-type Drosophila melanogaster cohorts (w1118/+) were treated with different Δ9-tetrahydrocannabinol (THC) and CBD dosages and examined for neural protective properties using established neural aging and trauma models. The therapeutic potential of each compound was assessed using circadian and locomotor behavioral assays and longevity profiles. Changes to NF-κB pathway activation were assessed by measuring expression levels of downstream targets using quantitative real-time polymerase chain reaction analysis of neural cDNAs. Results: Flies exposed to different CBD or THC dosages showed minimal effects to sleep and circadian-based behaviors or the age-dependent decline in locomotion. The 2-week CBD (3 μM) treatment did significantly enhance longevity. Flies exposed to different CBD and THC dosages were also examined under stress conditions, using the Drosophila mild traumatic brain injury (mTBI) model (10×). Pretreatment with either compound did not alter baseline expression of key inflammatory markers (NF-κB targets), but did reduce neural mRNA profiles at a key 4-h time point following mTBI exposure. Locomotor responses were also significantly improved 1 and 2 weeks following mTBI. After mTBI (10×) exposure, the 48-h mortality rate improved for CBD (3 μM)-treated flies, as were global average longevity profiles for other CBD doses tested. While not significant, THC (0.1 μM)-treated flies show a net positive impact on acute mortality and longevity profiles following mTBI (10×) exposure. Conclusions: This study shows that the CBD and THC dosages examined had at most a modest impact on basal neural function, while demonstrating that CBD treatments had significant neural protective properties for flies following exposure to traumatic injury.

The Interaction of Opiate Misuse and Marijuana Use on Behavioral Health Outcomes Using the Traumatic Brain Injury Model Systems Pain Collaborative Dataset

OBJECTIVE

To determine if the interaction of opiate misuse and marijuana use frequency is associated with behavioral health outcomes.

SETTING

Community.

PARTICIPANTS

Three thousand seven hundred fifty participants enrolled in the Traumatic Brain Injury Model Systems who completed the Pain Survey and had complete opioid use and marijuana use information.

DESIGN

Cross-sectional, secondary analysis from a multisite observational cohort.

MAIN OUTCOME MEASURES

Clinically significant behavioral health symptoms for posttraumatic stress disorder (PTSD), depression, anxiety, and sleep quality.

RESULTS

Three thousand five hundred thirty-five (94.3%) participants did not misuse opiates, 215 (5.7%) did misuse opiates (taking more opioid pain medication than prescribed and/or using nonprescription opioid pain medication); 2683 (70.5%) participants did not use marijuana, 353 (9.3%) occasionally used marijuana (less than once a week), and 714 (18.8%) regularly used marijuana (once a week or more frequently). There was a statistically significant relationship (P < .05) between the interaction of opiate misuse and marijuana use frequency and all behavioral health outcomes and several covariates (age, sex, cause of injury, severity of injury, and pain group category). Pairwise comparisons confirm that statistically significant associations on behavioral health outcomes are driven by endorsing opiate misuse and/or regular marijuana use, but occasional marijuana use was not associated.

CONCLUSIONS

Higher odds of clinically significant PTSD, depression, anxiety, and poor sleep quality are present in people with traumatic brain injury (TBI) who misuse opiates and/or who use marijuana regularly. In the absence of opiate misuse, regular marijuana use had higher odds of worse behavioral health outcomes than occasional and no use. The interaction of opiate misuse and regular marijuana use yielded the highest odds. Individuals with TBI should be informed of the relationship of substance use and behavioral health outcomes and that current chronic pain may mediate the association.

Negative experiences of patients using medicinal cannabis: A systematic review of qualitative studies

AIMS AND OBJECTIVES

In this study, we systematically reviewed qualitative studies concerning patients' experience with medicinal cannabis (MC) use, to gain insight into the negative effects of MC.

BACKGROUND

Over the past decades, the use of MC for therapeutic purposes has increased. However, there is conflicting and insufficient data on possible negative physiological and psychological effects of MC treatment.

DESIGN

A systematic review was conducted and the PRISMA guidelines were adopted. Literature searches were conducted using PubMed, PsycINFO and EMBASE. Critical Appraisal Skills Programme (CASP) qualitative checklist used to assess risk of bias in the included studies.

METHODS

We included studies focusing on conventional medical treatment using cannabis-based products, approved by a physician for a particular health issue.

RESULTS

Of the 1230 articles identified in the initial search, eight articles were included in the review. Following the compilation of themes in the eligible studies, six themes were identified: (1) MC approval; (2) administrative barriers; (3) social perception; (4) MC misuse/widespread effect; (5) adverse effects; and (6) dependence or addiction. These were grouped into two meta-themes: (1) administrative and social aspects of MC use; and (2) experiences of the effects of medicinal cannabis.

CONCLUSIONS

Our findings call for specific attention to unique consequences associated with MC use. Further research is needed in order to assess the degree to which negative experiences associated with MC use may affect various aspects of patients' medical condition.

RELEVANCE TO CLINICAL PRACTICE

Describing the complex experience of MC treatment and its spectrum of consequences for patients may enable physicians, therapists and researchers to provide more attentive and accurate MC treatment to their patients.

PATIENT OR PUBLIC CONTRIBUTION

In this review, patients' narratives were explored, yet the research methods did not directly involve patients or the public.