Evaluating the impact of cannabinoids on sleep health and pain in patients with chronic neuropathic pain: a systematic review and meta-analysis of randomized controlled trials

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“Background: Chronic neuropathic pain is often debilitating and can have a significant impact on sleep health and quality of life. There is limited information on the impact of cannabinoids on sleep health when treating neuropathic pain.

Objective: The objectives of this systematic review and meta-analysis were to determine the effect of cannabinoids on sleep quality, pain intensity, and patient impression of treatment efficacy in patients with neuropathic pain.

Evidence review: Nine available medical literature databases were searched for randomized controlled trials comparing synthetic and natural cannabinoids to placebo in patients with neuropathic pain syndromes. Data on validated tools for sleep quality, pain intensity, patients’ global impression of change (PGIC), and incidence of adverse effects of cannabinoids were extracted and synthesized.

Findings: Of the 3491 studies screened, eight randomized controlled trials satisfied the inclusion criteria for this review. Analyses were performed using R -4.1.2. using the metafor package and are interpreted using alpha=0.05 as the threshold for statistical significance. Validated measures for sleep health were not used in most studies. Meta-analysis of data from six studies showed that cannabinoids were associated with a significant improvement in sleep quality (standardized mean difference (SMD): 0.40; 95% CI: 0.19 to -0.61, 95% prediction interval (PI): -0.12 to 0.88, p-value=0.002, I2=55.26, τ2=0.05, Q-statistic=16.72, GRADE: moderate certainty). Meta-analysis of data from eight studies showed a significant reduction in daily pain scores in the cannabinoid (CB) group (SMD: -0.55, 95% CI:-0.69 to -0.19, 95% PI: -1.51 to 0.39, p=0.003, I2=82.49, τ2=0.20, Q-statistic=47.69, GRADE: moderate certainty). However, sleep health and analgesic benefits were associated with a higher likelihood of experiencing daytime somnolence, nausea, and dizziness.

Conclusions: Cannabinoids have a role in treating chronic neuropathic pain as evidenced by significant improvements in sleep quality, pain intensity, and PGIC. More research is needed to comprehensively evaluate the impact of cannabinoids on sleep health and analgesic efficacy.”

https://pubmed.ncbi.nlm.nih.gov/36598058/

https://rapm.bmj.com/content/early/2022/12/04/rapm-2021-103431

Cannabidiol-rich non-psychotropic Cannabis sativa L. oils attenuate peripheral neuropathy symptoms by regulation of CB2-mediated microglial neuroinflammation

“Neuropathic pain (NP) is a chronic disease that affects the normal quality of life of patients. To date, the therapies available are only symptomatic and they are unable to reduce the progression of the disease. Many studies reported the efficacy of Cannabis sativa L. (C. sativa) on NP, but no Δ9 -tetrahydrocannabinol (Δ9 -THC)-free extracts have been investigated in detail for this activity so far. The principal aim of this work is to investigate the potential pain-relieving effect of innovative cannabidiol-rich non-psychotropic C. sativa oils, with a high content of terpenes (K2), compared to the same extract devoid of terpenes (K1). Oral administration of K2 (25 mg kg-1 ) induced a rapid and long-lasting relief of pain hypersensitivity in a mice model of peripheral neuropathy. In spinal cord samples, K2 reduced mitogen-activated protein kinase (MAPKs) levels and neuroinflammatory factors. These effects were reverted by the administration of a CB2 antagonist (AM630), but not by a CB1 antagonist (AM251). Conversely, K1 showed a lower efficacy in the absence of CB1/CB2-mediated mechanisms. In LPS-stimulated murine microglial cells (BV2), K2 reduced microglia pro-inflammatory phenotype through the downregulation of histone deacetylase 1 (HDAC-1) and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (IKBα) and increased interleukin-10 (IL-10) expression, an important antiinflammatory cytokine. In conclusion, these results suggested that K2 oral administration attenuated NP symptoms by reducing spinal neuroinflammation and underline the important role of the synergism between cannabinoids and terpenes.”

https://pubmed.ncbi.nlm.nih.gov/36583304/

https://onlinelibrary.wiley.com/doi/10.1002/ptr.7710

Drug-Drug Interaction Between Orally Administered Hydrocodone-Acetaminophen and Inhalation of Cannabis Smoke: A Case Report

SAGE Journals Home

“Objective: To determine if a 2-day protocol measuring pharmacokinetic and pharmacodynamic characteristics can demonstrate drug-drug interactions when smoked cannabis is added to orally administered hydrocodone/acetaminophen combination products.

Case summary: A 51-year-old non-Hispanic white male with chronic pain diagnoses participated in a 2-day pilot protocol. The participant attended two 7-hour in-lab days where he received 10 blood draws each day and completed self-administered pain and anxiety surveys. For both days, the participant took his prescribed dose of hydrocodone/acetaminophen (1/2 tablet of 7.5 mg/325 mg combination product) with the addition of 1 smoked pre-rolled marijuana cigarette (labeled as 0.5 g; 22.17% Δ9-tetrahydrocannabinol; 0.12% cannabidiol) on Day 2. Blood specimens were analyzed using mass spectrometry to quantify the difference of plasma hydrocodone levels between Day 1 and Day 2.

Results: Compared to Day 1, lower levels of pain and anxiety were reported during Day 2 with the addition of cannabis to oral hydrocodone/acetaminophen. Day 2 pharmacokinetic analysis also revealed more rapid absorption and overall lower levels of hydrocodone in plasma.

Discussion: Lower hydrocodone plasma levels in Day 2 may indicate cannabis’s effect on metabolism and reduce the risk of opioid toxicity. The quicker absorption rate of hydrocodone could explain lower pain and anxiety scores reported on the second day.

Conclusion and relevance: A 2-day protocol was able to capture differences across time in pharmacokinetic and pharmacodynamic measurements. Larger studies can be designed to better characterize the potential drug-drug interaction of cannabis and opioids.”

https://pubmed.ncbi.nlm.nih.gov/35898257/

https://journals.sagepub.com/doi/10.1177/00185787211061374

The Utility of Cannabis-Based Medicine in Chronic Pain Management: A Case Report

“Chronic pain is a common diagnosis that patients may face, resulting in increased morbidity and mortality and affecting the overall quality of life.

In addition to established multidisciplinary pain management, medical cannabis may offer an approach to improving pain outcomes and functionality. This case involves a 72-year-old female patient, with chronic neck, lower back, and diffuse arthritic pain due to comorbid osteoarthritis (OA), scleroderma, and scoliosis. Medical cannabis therapy was certified based on the goals of improving pain control and simultaneously reducing the patient’s chronic opioid medication dose.

Using potential opioid alternatives, such as medical cannabis, may prove beneficial to clinicians looking to improve pain management and reduce opioid therapy in patients.”

https://pubmed.ncbi.nlm.nih.gov/36540475/

“This case indicates that cannabinoid therapy may be useful in managing chronic pain and therein reducing its detrimental impact on patients’ overall quality of life. Potential opioid alternatives, such as medical cannabis, are becoming increasingly important in pain management to improve patients’ quality of life. Additionally, this case demonstrates that medical cannabis may prove beneficial in reducing reliance on chronic opioid therapy. Clinicians should be aware of different approaches to treatment that do not include opioids.”

https://www.cureus.com/articles/113524-the-utility-of-cannabis-based-medicine-in-chronic-pain-management-a-case-report

The Use of Cannabidiol in Patients With Low Back Pain Caused by Lumbar Spinal Stenosis: An Observational Study

cureus – Retraction Watch

“Spinal stenosis is a degenerative narrowing of the spinal canal with encroachment on the neural structures by surrounding bone and soft tissue. This chronic low back condition can cause restrictions in mobility, impairment of daily activities, opioid dependence, anxiety, depression, and reduced quality of life. Spinal stenosis can be treated through surgical and nonsurgical methods, but neither has proven consistently reliable.

Cannabidiol (CBD) has also been observed to have anxiolytic, anti-inflammatory, antiemetic, and antipsychotic behaviors. CBD may provide greater nonsurgical treatment options for the pain associated with spinal stenosis while minimizing the need for opioids.

An observational study was undertaken to assess the effects of CBD on patients suffering from chronic spinal stenosis.

This observational study was investigator-initiated and designed to determine the effect of hemp-derived CBD gel caps for patients with spinal stenosis related to low back pain and leg pain relative to patient outcomes, medication utilization, and quality of life outcome measures. A total of six physician visits would be required where a set of surveys would be filled out each four weeks apart.

Results The study population consisted of 48 patients. The patient population’s age ranged from 63 to 95 years and was normally distributed, with a mean age of 75 ± 7.13 years. The sex distribution was 33% male and 67% female patients. The pain was broken down between the six visits for each of the following four questions: pain right now, usual pain level during the week, best pain level during the week, and worst pain level during the week. Usual pain levels (p < 0.001) and worst pain levels (p < 0.005) demonstrated statistically significant improvement over time, while pain right now (p > 0.05) and best pain level (p > 0.05) stayed consistent throughout without statistical significance.

Conclusions This open-label, prospective, observational study found that treatment with hemp-derived CBD gel caps was associated with significant improvements in pain scores and several quality-of-life measures for patients with lumbar spinal stenosis.”

https://pubmed.ncbi.nlm.nih.gov/36507111/

“This open-label, prospective, observational study found that treatment with hemp-derived CBD gel caps was associated with significant improvements in pain scores and several quality-of-life measures for patients with lumbar spinal stenosis.”

https://www.cureus.com/articles/106551-the-use-of-cannabidiol-in-patients-with-low-back-pain-caused-by-lumbar-spinal-stenosis-an-observational-study

Comparing Sublingual and Inhaled Cannabis Therapies for Low Back Pain: An Observational Open-Label Study

Rambam Maimonides Medical Journal - Thailand Medical News

“Background and objective: Medical cannabis is becoming an acceptable treatment modality in medicine, especially for pain relief. Concurrently, cannabis use is becoming more prevalent worldwide, a public demand-driven trend despite the lack of established scientific basis. This observational open-label study sought to investigate the effectiveness of cannabis therapy for alleviating low back pain symptoms.

Methods: Two types of cannabis treatment modalities were sequentially administered to chronic low back pain patients. After an initial 1-month washout period (WO1), the first modality was cannabidiol (CBD)-rich sublingual extract treatment administered for 10 months. Following another washout period, the second modality, Δ9-tetrahydrocannabinol (THC)-rich smoked inflorescence (whole dried cannabis flowers) was administered for 12 months.

Results: Enrolled in the study were 24 patients whose advanced imaging studies (i.e. computerized tomography or magnetic resonance imaging of the lumbar spine) revealed disc herniation or spinal stenosis. Three patients dropped out of extract therapy treatment but resumed study participation to receive THC-rich smoking therapy. After a minimum of 2 years, cannabis therapy had reduced lower back pain symptoms, as assessed by Oswestry Disability Index, the SF-12 patient-reported outcome questionnaire, and the visual analogue scale. Pain reduction was not significant during the extract treatment part of the study; however, pain reduction was significant during the inhaled therapy part of the study.

Conclusions: Our findings indicate that inhaled THC-rich therapy is more effective than CBD-rich sublingual extract therapy for treating low back pain and that cannabis therapy is safe and effective for chronic low back pain.”

https://pubmed.ncbi.nlm.nih.gov/36394500/

https://www.rmmj.org.il/issues/55/articles/1518

Safety and Effectiveness of Cannabinoids to Danish Patients with Treatment Refractory Chronic Pain – A Retrospective Observational Real-world Study

“Background: Cannabinoids are considered a therapeutic option to patients suffering from treatment refractory chronic pain (TRCP) insufficiently relieved by conventional analgesics or experiencing intolerable adverse events (AEs) from those. This study aimed to explore safety and effectiveness of oral cannabinoids among patients with TRCP.

Methods: A retrospective study was conducted among Danish patients with TRCP being prescribed oral cannabinoids. Data on AEs and changes in pain intensity by numeric rating scale (NRS) before and after initiation of oral cannabinoid therapy were analyzed.

Results: Among 826 eligible patients ≥ 18 years old, 529 (64%) were included for data analysis at first follow- up (F/U1) (median 56 days from baseline) and 214 (26%) for second follow-up (F/U2) (median 126 days from F/U1). Mean age was 60±15.9 years and 70% were females. AEs were in general reported mild to moderate by 42% of patients at F/U1 and 34% at F/U2. AEs were mainly related to gastrointestinal (F/U1: 17% and F/U2: 13%) and nervous system disorders (F/U1: 14% and F/U2: 11%). Reduction in NRS was significantly different at both follow-up consultations compared with baseline (<.0001). Clinically relevant pain reduction (NRS ≥30%) was reported by 17% at F/U1 and 10% of patients at F/U2 in intention-to-treat analysis whereas the figures were 32% and 45% respectively, in per-protocol analysis.

Conclusion: Oral cannabinoid therapy seems to be safe and mildly effective in patients with TRCP. Randomized controlled trials with focus on comparable pain characteristics in diagnostical homogenous patient subgroups are needed for further improvement of evidence level for relief of chronic pain using oral cannabinoids.”

https://pubmed.ncbi.nlm.nih.gov/36394124/

https://onlinelibrary.wiley.com/doi/10.1002/ejp.2054

Medical Cannabinoids as Treatment for Hypophosphatasia-Related Symptoms

Karger Publishers – ScienceOpen

“Background: Hypophosphatasia (HPP) is a rare congenital disease caused by a mutation affecting tissue non-specific alkaline phosphatase, an enzyme involved in phosphate metabolism. The clinical manifestation usually includes bone-mineralization disorders, neurological symptoms, and persistent muscle pain.

Case report: This case involves a woman in her sixties of Central European descent who suffers from life-long chronic pain and muscle weakness due to hypophosphatasia and concomitant degenerative changes of the lumbar spine. The patient is physically impaired and limited in her ability to walk as a result. HPP-specific and guideline-based multimodal pain management including enzyme replacement therapy with asfotase alfa, opioids, invasive orthopedic and neurosurgical procedures, long-term physiotherapy, and psychotherapy did not yield sufficient treatment results. The average pain was given as 8.5 on a numerical rating scale (NRS, 0-10) for the last 3 years. Treatment with a cannabidiol-predominant, full-spectrum, prescription cannabis extract led to a clinically meaningful pain reduction to 2.5/10 NRS, a discontinuation of opioids, and a recent resumption of employment as a physician.

Conclusion: A more widespread consideration of medical cannabinoids in the treatment of complex chronic pain is proposed. Cannabinoids may pose a particularly potent treatment option for HPP-related symptoms and inflammation due to their known anti-inflammatory properties.”

https://pubmed.ncbi.nlm.nih.gov/36380652/

https://www.karger.com/Article/Abstract/528069

Chronic Pain and Cannabidiol in Animal Models: Behavioral Pharmacology and Future Perspectives

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“The incidence of chronic pain is around 8% in the general population, and its impact on quality of life, mood, and sleep exceeds the burden of its causal pathology. Chronic pain is a complex and multifaceted problem with few effective and safe treatment options. It can be associated with neurological diseases, peripheral injuries or central trauma, or some maladaptation to traumatic or emotional events. In this perspective, animal models are used to assess the manifestations of neuropathy, such as allodynia and hyperalgesia, through nociceptive tests, such as von Frey, Hargreaves, hot plate, tail-flick, Randall & Selitto, and others. Cannabidiol (CBD) has been considered a promising strategy for treating chronic pain and diseases that have pain as a consequence of neuropathy. However, despite the growing body of evidence linking the efficacy of CBD on pain management in clinical and basic research, there is a lack of reviews focusing on chronic pain assessments, especially when considering pre-clinical studies, which assess chronic pain as a disease by itself or as a consequence of trauma or peripheral or central disease. Therefore, this review focused only on studies that fit our inclusion criteria: (1) used treatment with CBD extract; (2) used tests to assess mechanical or thermal nociception in at least one of the following most commonly used tests (von Frey, hot plate, acetone, Hargreaves, tail-flick, Randall & Selitto, and others); and (3) studies that assessed pain sensitivity in chronic pain induction models. The current literature points out that CBD is a well-tolerated and safe natural compound that exerts analgesic effects, decreasing hyperalgesia, and mechanical/thermal allodynia in several animal models of pain and patients. In addition, CBD presents several molecular and cellular mechanisms of action involved in its positive effects on chronic pain. In conclusion, using CBD seems to be a promising strategy to overcome the lack of efficacy of conventional treatment for chronic pain.”

https://pubmed.ncbi.nlm.nih.gov/36355044/

https://www.liebertpub.com/doi/10.1089/can.2022.0096

Medical Cannabis Use and Inflammatory Cytokines and Chemokines Among Adult Chronic Pain Patients

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“Background: Utilizing cannabis as a therapeutic option for chronic pain (CP) has increased significantly. However, data regarding the potential immunomodulatory effects of cannabis in CP patients remain scarce. We aimed at exploring the relationship between cannabis use and inflammatory cytokines and chemokines among a cohort of CP patients. 

Methods: Adult patients with a CP diagnosis and medical authorization of cannabis were enrolled. Patients completed validated clinical questionnaires and self-reported the effectiveness of cannabis for symptom management. Patients’ blood and cannabis samples were analyzed for the presence of four major cannabinoids, two major cannabinoid metabolites, 29 different cytokines/chemokines, and cortisol. The multivariable linear regression model was used to identify cannabis and patient factors associated with immune markers. 

Results: Fifty-six patients (48±15 years; 64% females) were included, with dried cannabis (53%) being the most common type of cannabis consumed. Seventy percent of products were considered delta-9-tetrahydrocannabinol (Δ9-THC)-dominant. The majority of patients (96%) self-reported effective pain management, and 76% reported a significant decrease in analgesic medication usage (p≤0.001). Compared with males, female patients had higher plasma levels of cannabidiol (CBD), cannabidiolic acid, Δ9-THC, and 11-hydroxy-Δ9-tetrahydrocannabinol but lower concentrations of delta-9-tetrahydrocannabinolic acid and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH). Females had significantly lower eotaxin levels (p=0.04) in comparison to male patients. The regression analysis indicated that high cannabis doses were related to increased levels of interleukin (IL)-12p40 (p=0.02) and IL-6 (p=0.01), whereas female sex was associated with decreased eotaxin (p≤0.01) concentrations. Blood CBD levels were associated with lower vascular endothelial growth factor (p=0.04) concentrations, and THC-COOH was a factor related to decreased tumor necrosis factor alpha (p=0.02) and IL-12p70 (p=0.03). 

Conclusion: This study provides further support for the patient-perceived effectiveness of cannabis in managing CP symptoms and reducing analgesic medication consumption. The results suggest a potential sex difference in metabolizing cannabinoids, and the varying immune marker concentrations may support a possible immunomodulatory effect associated with patient sex and cannabis product type. These preliminary findings provide grounds for further validation using larger, well-designed studies with longer follow-up periods.”

https://pubmed.ncbi.nlm.nih.gov/36342776/

https://www.liebertpub.com/doi/10.1089/can.2022.0143