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Take a look at a selection of our recent media coverage:
18th May 2023
Patients’ self-reported, health-related quality of life significantly improves in all domains following use of medical cannabis, research shows.
Use of medical cannabis significantly improves all domains on the 36-item Short Form Health Survey (SF-36), which looks at health-related quality-of-life, according to the findings of a recent study by Australian researchers.
A legal framework to allow prescription of medical cannabis in Australia has been available since 2016. Moreover, a 2022 systematic review found that cannabinoids are effective for several indications including epilepsy and chronic pain. The term ‘medical cannabis’ refers to a wide array of products, such as dried flowers and oils, that contain bioactive constituents in addition to tetrahydrocannabinol and cannabidiol.
However, the lack of randomised trial data means clinicians cannot know with any level of certainty whether a particular medical cannabis product would be efficacious. Nevertheless, one means through which clinicians can gain a better understanding of the impact of medical cannabis is through an assessment of health-related quality of life.
This was the subject of a recent study published in JAMA Network Open. Australian researchers assessed if use of medical cannabis led to improvements in health-related quality of life and if these benefits persisted over time. The team retrospectively reviewed the medical records of those prescribed medical cannabis across the country. The outcome of interest was the change in health-related quality of life based on changes from baseline in the SF-36. This questionnaire consists of eight domains that evaluate the impact of an intervention, such as medical cannabis, on several measures including physical and mental health, body pain and physical functioning.
A total of 3,148 patients with mean age 55.9 years (53.6% female) had usable data for analysis and 15 follow-up consultations were examined for each patient.
Medical cannabis was used mainly for chronic non-cancer pain (68.6%), cancer pain (6%), insomnia (4.8%) and anxiety (4.2%). After commencing treatment, significant improvements occurred in all eight domains of the SF-36. After controlling for potential confounders, SF-36 domain scores increased from 6.6 to 18.31, (all with p <0.001). Moreover, these improvements largely persisted over time.
Despite the clear benefits to quality of life, the researchers noted a total of 2,919 self-reported adverse events, with at least two considered serious. They concluded that clinicians should exercise caution in the prescription of medical cannabis, avoiding where possible in those with known contra-indications.
17th October 2022
Medicinal cannabis use appears to be associated with a reduction in patient’s use of opiate-based analgesics and improvements in self-reported physical functioning according to a study by US researchers.
In the US there has been an opiate crisis of epidemic proportions. Data from the CDC indicate that in the year ending in June 2020, 48,006 deaths were attributable to overdosing on synthetic opioids other than methadone. Fortunately, it appears that the level of opiate-related deaths in the US is beginning to fall with a slight decrease in 2019 compared to 2017. Although there may be any number of reasons as to why deaths are falling, one potential explanation for this reduction is greater use of medicinal cannabis (MC) use compared to opiates. In fact, a 2017 study identified how patients reported less use of opiates, antidepressants, alcohol, anti-anxiety, migraine and sleep medications after using MC. Despite this possible rise in use, an overview of the efficacy, tolerability and safety of cannabis-based medicines for chronic pain management concluded that there were inconsistent findings of the efficacy of cannabinoids in neuropathic pain, painful spasms in multiple sclerosis and for any chronic pain. However, many US states have taken steps to legalise and decriminalise the use of MC. As a result, for the present study, the US team sought to characterise the demographics and use patterns of those who had physician-approved medical cannabis access and to examine patient’s perceptions of changes in health functioning and use of opiate-based pain medicines (OBPM) after access to MC. The team developed a 66-item questionnaire that was distributed online, assessing a wide range of factors including demographics, medical conditions, health functioning and changes in pain medication use before and after use of MC.
Medicinal cannabis and changes to opiate-based medicine use
A total of 2,183 responses were included of whom 54.4% were female and nearly two thirds (64.9%) were aged 30 to 59. A third (33%) of respondents reported that they had 6 or more ailments and nearly half (47.9%) reported having pain and mental health issues, whereas pain alone was reported by only 9.1%.
The majority (54.9%) reported using medicinal cannabis regularly throughout the day and 7.8% had been using medicinal cannabis for more than 10 years.
In terms of physical functioning, bodily pain (e.g., the level of pain or interference of pain in normal work) was reportedly improved by 89.6% of respondents after use of MC, as was social functioning (84.3%).
Prior to MC usage, 60.9% of respondents were using OBPM with 36.8% using hydrocodone-acetaminophen (paracetamol) or oxycodone-acetaminophen (26.8%). However, after using MC, 41.7% reported that they had stopped using pain medicines and 37.5% had reduced their pain medicines. Interestingly, 11.5% reported improved functioning after using MC and reducing their OBPM.
The authors concluded that medicinal cannabis may play an important role at both the individual and community level as a viable alternative to opioids for pain management and without negatively affecting health functioning.
Prtichett CE et al. Medical Cannabis Patients Report Improvements in Health Functioning and Reductions in Opiate Use Subst Use Misuse 2022
25th October 2021
An anonymous survey of cannabis (CB) use found that 42% of women with breast cancer were using it for the relief of symptoms, according research conducted by the online support group, Breastcancer.org, Pennsylvania, US. The use of medicinal CB among those with cancer is not new and has previously been reported by nearly a quarter of respondents with a range of different cancer and mostly for pain relief. In addition, other work has found that 1 in 5 patients of those with cancer admitted to taking CB during chemotherapy. Although in the US, federal law states that the possession of cannabis is illegal, except within approved research settings, as of May 2021, 36 states and four territories allow for the medical use of cannabis products and in many cases, this can be for cancer.
For the present study, the researchers developed their survey and posted it online and members of Breastcancer.org were invited to participate through messaging boards, social media and email newsletters. The survey collected demographic data as well as breast cancer variables e.g., type, stage and treatment status, together with information on their use of cannabis such as timing of use in relation to therapy, e.g., before, during or after treatment, products used, sources and perceptions of the safety of cannabis.
A total of 612 completed surveys were available for analysis from women with a mean age of 57 years. A total of 64% of respondents reported being very or extremely interested in the medicinal use of cannabis, with the most common source of information being websites (67%) and family and friends (56%). However, only 39% had discussed the use of CB with their physician.
Overall, 42% (257/612) reported having used cannabis although only 23% (58) mentioned that this was specifically for medical purposes, with the remainder using it both medically and for recreational purposes. Among the 257 respondents using cannabis, 79% had used it alongside conventional treatment and 54% reported using it after the completion of therapy. The most common reasons for taking cannabis were for the relief of pain (78%), insomnia (70%), anxiety (57%), stress (50%) and nausea/vomiting (46%). Moreover, 75% of those using CB believed that it was extremely or very helpful, at relieving their symptoms. Of more concern, was that 57% of those using cannabis stated that this was because they found no other way of treating their symptoms and how 49% stated that they were using CB in the belief that it could treat their cancer.
Interestingly, 78% of respondents somewhat or strongly agreed, that cannabis should be viewed similarly to other plant-based medicines with 71% stating that the benefits of cannabis outweighed its risks.
Commenting on their findings, the researchers noted how the use of CB during therapy was a concern, given the limited data available on interactions. In addition, they suggested that medical providers should discuss the risks and benefits of using CB in those with cancer.
Weiss MC et al. A Coala-T-Cannabis Survey Study of Breast Cancer Patients’ Use of Cannabis Before, During, and After Treatment. Cancer 2021
21st September 2021
In a 2006 European survey of over 46,000 respondents in 15 countries, 19% reported experiencing pain which lasted for at least 6 months. Moreover, a more recent 2019 study in developing countries found a similar incidence (18%) among the general population. However, the impact of chronic pain, i.e., which persists past the normal healing time and lasts or recurs for more than 3 to 6 months, has a much wider impact upon affected individuals, reducing physical functioning, daily activities and mental health. Although opioid drugs have been used for the management of chronic pain, evidence suggests that compared with placebo, there are only small beneficial effects. Consequently, there has been increased interest in the use of alternative pain management strategies, one of which is the use of medical cannabis. In fact, its use as a therapeutic alternative has been recommended in some guidance for chronic pain, especially in cases where other treatments have been ineffective. However, the overall effectiveness of medical cannabis in chronic pain remains unclear with some organisations such as NICE in the UK, advising against the use of cannabis-based medicinal products to manage chronic pain in adults unless as part of a clinical trial.
With uncertainty over the effectiveness of medical cannabis in chronic pain, Canadian researchers led by a team from the Department of Anesthesia, McMaster University, Ontario, Canada, performed a systematic review and meta-analysis to determine the benefits and harms of medical cannabis in patients with chronic pain, including cancer pain. They included randomised controlled trials that enrolled at least 20 patients with chronic pain (defined as lasting longer than 3 months) and who were assigned to any form of medical cannabis and which was compared to placebo with a follow-up period of at least one month. As well as the impact on pain, the team also captured data on physical, emotional and social functioning and sleep quality. They assessment the benefits in terms of change scores from baseline as opposed to end of study results and determined whether use of cannabis achieved the minimally important difference (MID). This represents the smallest amount of improvement in a treatment outcome that patients recognise as important. For example, using a 10 cm visual analogue scale for pain, the MID is approximately 1 cm. The researchers modelled the risk difference (RD) of achieving at least the MID.
A total of 32 trials with 5174 adults in which 29 compared medical cannabis with placebo were included in the analysis. In terms of pain relief, there was moderate certainty evidence from 27 trials that medical cannabis compared to placebo, resulted in a small increase in the proportion of patients experiencing pain relief at or above the MID. This difference was modelled as 10 % (95% CI 5% to 15%). Data from 10 trials suggested a 7% increase in the proportion of patient experiencing at least a 30% reduction in pain with medical cannabis compared to placebo. Similarly, there was a 4% modelled difference in physical functioning and a 6% modelled risk difference for an improvement in sleep quality. However, there was no apparent improvement in emotional or social functioning. With respect to adverse effects, it appeared that medical cannabis gave rise to a 2% risk of transient cognitive impairment, impaired attention (3%) and nausea (5%).
The authors concluded that there was moderate to high certainty evidence of a small to very small increase in the proportion if people with chronic pain who experience an important improvement in their pain. Their results have been summarised in an accompanying rapid recommendation.
4th December 2020
Whether or not, cannabidiol, the derivative widely used as medicinal cannabis, also impairs driving performance is largely unknown.
Cannabis is available in three different varieties (or technically, chemovars) which are cannabidiol (CBD) dominant, tetrahydrocannabinol (THC) dominant and a CBD-THC equivalent mixture. Individuals inhale the THC dominant form because of its intoxicating effects. Whether the CBD dominant form, used medicinally, has sedating properties is currently equivocal.
As a result, researchers from the Lambert Initiative for Cannabinoid Research, University of Sidney, Australia, conducted a randomised trial to examine the extent and duration to which each of the different cannabis chemovars impaired driving performance. They recruited 26 individuals with a history of occasional cannabis use and employed a cross-over design study that involved four on-road driving periods, one week apart.
For the study, the participants inhaled one of vapourised cannabis containing 13.75mg CBD, THC, CBD-THC equal mixture or placebo. The driving tests twice; 40 to 100 minutes and 240 to 300 minutes post-vaporisation. The primary outcome was the mean standard deviation of lateral position (SDLP), which measures the extent of lane weaving, swerving and overcorrecting.
The mean age of the 26 individuals was 23.2 years (including 16 women), all of whom completed the 8 driving tests. At 40 to 100 minutes and following inhalation of cannabis, the mean SDLP after CBD was 84.07cm, 86.94cm after THC, 84.07cm after the CBD-THC mixture and 84.41cm after placebo and these values remained similar between 240 and 300 minutes.
Pairwise comparisons revealed that both SDLP values for THC and the THC-CBD were higher than placebo at 40 to 100 minutes, but not between 240 and 300 minutes. In other words, both THC and the combination but not, CBD, impaired driving performance in the short-term, but that this effect was abolished in the longer term.
Although a limitation in the study, recognised by the authors, was that the dosages used might not reflect common usage, their data implied that CBD did not affect driving ability.
Arkell TR et al. Effect of cannabidiol and delta-nine tetrahydrocannabiniol on driving performance. A randomised clinical trial. JAMA Net Open 2020 doi:10.1001/jama.2020.21218.