The Effect of Cannabis-Based Medicine in the Treatment of Cachexia: A Systematic Review and Meta-Analysis.

Background: Cachexia is a prevalent condition associated with underlying chronic disease. Wasting of skeletal muscle and adipose tissue loss in cachectic patients is associated with higher rates of disability, reduced quality of life (QoL), and worse prognosis. There is a large unmet need to develop strategies to treat cachexia as there are currently no standardized guidelines in the management of cachexia. Activation of endogenous cannabinoid receptors, through exogenous cannabinoids, has demonstrated potential in increasing appetite, reducing catabolism, and has shown anti-inflammatory properties. Since no single pharmacological agent is currently recommended for use in cachexia, the potential of cannabinoids as an appetite stimulant warrants further research and assessment of current evidence. Objective: This review aims to evaluate the evidence for the efficacy of cannabis-based medicinal products, against placebo and other active treatments, in anorexia-cachexia syndrome in improving appetite, weight, and QoL. Methods: A literature search of the Medline, EMBASE, CENTRAL, and the Web of Science Core Collection, for articles published up to February 2020, was conducted. All randomized controlled trials comparing the use of cannabis-based medicine versus placebo/active treatments for patients with cachexia were screened. The quality of evidence in included studies was assessed using the GRADE framework and any risk of bias was judged using the Cochrane risk of bias tool. Results: A total of five studies, encompassing 934 participants, were found to be eligible. The pooled group effect size for change in appetite was -1.79 (95% confidence interval: -3.77 to 0.19) favoring the control group (p=0.08). Additionally, no significant difference for weight change or change in QoL for cannabinoids versus placebo/other treatment was observed. The quality of evidence for all five studies was assessed to be low. Conclusion: There is a lack of high-quality evidence to recommend the use of cannabinoids in the treatment of cachexia. Given the limited available pharmacological options for cachexia and the potential for cannabinoids to increase appetite and alter the immune system, further research is needed before clinical recommendations on the pharmacological management of cachexia can be made.