Patient Counseling Guidelines for the Use of Cannabis for the Treatment of Chemotherapy-Induced Nausea/Vomiting and Chronic Pain

Cannabis induced psychosis: a systematic review on the role of genetic polymorphisms

OBJECTIVE

Cannabis sativa is a recreational drug commonly consumed in Europe and is getting popularity for both recreational and therapeutic use. In some individuals, the use of cannabis leads to psychotic disorders. This systematic review summarizes the current evidence linking genetic polymorphisms and inter-individual susceptibility to psychosis induced by cannabis.

METHOD

Studies published from 2005 to 2020 were identified through Medline using PubMed, Web of Science and Scopus database and searches were conducted according to PRISMA guidelines. Initial search was performed with terms: "cannabis induced psychosis" AND "genetics".

RESULTS

From the initial group of 108 papers, 18 studies met our inclusion criteria. Many of the findings revealed associations with genetic polymorphisms modulations of genes involved directly (COMT, DRD2 and DAT) or indirectly (AKT1) to dopamine pathways. The most consistent finding was with COMT rs4680, where the presence of the Val allele was associated with a higher risk for cannabis-induced psychosis. This higher susceptibility was also reported for AKT1 (rs2494732) with the CC genotype. Of note, the only genome-wide association study identified a significant signal close to the cholinergic receptor muscarinic 3 represented by rs115455482 and rs74722579 predisposing to cannabis-induced hallucinations and remarkably no dopaminergic target was found.

CONCLUSION

Actual evidence supports the role of dopamine in cannabis induced psychosis. However, most of genetic polymorphism studies have as a starting point the pre-existing dopaminergic theoretical basis for psychosis. This alerts to the importance of more broad genetic studies. Integrate genetic results into biological systems may enhance our knowledge of cannabis induced psychosis and could help in the prevention and treatment of these patients.

Gaps in evidence for the use of medically authorized cannabis: Ontario and Alberta, Canada

BACKGROUND

With legal access to medical cannabis in Canada since 2001, there is a need to fully characterize its use at both the individual and population levels. We draw on data from Canada's largest cohort study of medical cannabis to identify the primary reasons for medical cannabis authorization in Canada from 2014 to 2019 in two major provinces: Alberta (AB) and Ontario (ON), and review the extent that evidence supports each indication.

METHODS

Self-reported baseline assessments were collected from adult patients in ON (n = 61,835) and AB (n = 3410) who were authorized medical cannabis. At baseline, sociodemographic, primary medical information, and validated clinical questionnaires were completed by patients as part of an individual assessment. Patients' reasons for seeking medical cannabis were compared to published reviews and guidelines to assess the level of evidence supporting medical cannabis use for each condition.

RESULTS

Medical cannabis use in both AB and ON was similar in both demographic and reason for authorization. The most common reasons for medical cannabis authorization were: (1) pain (AB = 77%, ON = 76%) primarily due to chronic musculoskeletal, arthritic, and neuropathic pain, (2) mental health concerns (AB = 32.9%, ON = 38.7%) due to anxiety and depression, and (3) sleep problems (AB = 28%, ON = 25%). More than 50 other conditions were identified as reasons for obtaining authorization.

CONCLUSION

In both AB and ON, the majority of reasons for medical cannabis authorization are not substantiated by clinical evidence to fully support its efficacy for long-term use. Ongoing epidemiological studies on medical cannabis on these treatments are warranted to fully outline its treatment benefits or risks.

Chinese Herbal Medicine for Chemotherapy-Induced Leukopenia: A Systematic Review and Meta-Analysis of High-Quality Randomized Controlled Trials

Aim: We conducted a systematic review of high-quality randomized controlled trials (RCTs) to assess the efficacy and safety of Chinese herbal medicine (CHM) for the treatment of chemotherapy-induced leukopenia (CIL).

Methods: Eight electronic databases were searched from the date of inception to November 4, 2020 for high-quality RCTs that met the requirements of at least four key domains of the Cochrane risk of bias (RoB) tool. RevMan 5.3 was applied for the meta-analysis.

Results: Fourteen RCTs involving 1,053 patients were included. The pooled results showed that CHM + chemotherapy exerted greater beneficial effects on white blood cell (WBC), neutrophil (NEU), hemoglobin (Hb), and platelet (PLT) counts in addition to the Karnofsky performance scale (KPS) score, but showed no significant difference on granulocyte colony-stimulating factor (G-CSF) dosage compared with chemotherapy alone. Placebo (PBO) + chemotherapy and CHM + chemotherapy groups showed no significant differences in terms of reduction of the incidence of neutropenia. CHM + chemotherapy was superior to Western medicine (WM) + chemotherapy in improving the WBC count, KPS, infection amount, G-CSF use rate, and incidence of leukopenia. In addition, no severe adverse events were observed in the 14 RCTs.

Conclusion: CHM in combination with chemotherapy could effectively improve the clinical symptoms of CIL when compared with chemotherapy alone or Western medicine + chemotherapy, except when comparing with PBO + chemotherapy. While CHMs were generally safe for clinical use and exerted no severe side effects in the 14 RCTs, high-quality RCTs with larger sample sizes are essential to reduce study heterogeneity.

Therapeutic Application of Cannabis in Medicine and Its Relevance to Thoracic Surgery

BACKGROUND

Cannabis is the most commonly used illicit substance in the United States. As cannabis use rises in popularity and its legalization continues to expand, the scientific community must address the controversy between beneficial and adverse effects of cannabis consumption.

METHODS

We performed a comprehensive literature review to study the medicinal and pathologic effects of cannabis use, with emphasis on its association with cancer pathophysiology and thoracic surgery.

RESULTS

We found evidence that cannabis products often contain carcinogenic materials and that their use is associated with the development of certain head and neck cancers, but not lung cancer. Indeed, several in vitro and in vivo studies have demonstrated that cannabis may have a therapeutic role in cancer given the antiproliferative effects of its active compounds such as δ-9-tetrahydrocannabinol. Cannabis-derived products have also been shown to be effective treatments for chronic pain, neuropathy, spasticity, and as antiemetics.

CONCLUSIONS

We acknowledge that additional studies are required to elucidate the long-term effects of cannabis products and that many potential biases and limitations exist in the literature due to self-reporting and limited survey studies. Appropriate stewardship over cannabis use among our patient population will likely determine its full implications in both oncologic and perioperative outcomes.