Patients with chronic health conditions saw significant improvements in overall quality of life and reductions in fatigue during the first three months of medical marijuana use, according to a new study of more than 2,300 people. “Patients experiencing anxiety, depression, or chronic pain also improved in those outcomes over 3 months,” the study found.
Published this week in the journal PLoS ONE, the report analyzed responses from Australian patients eligible for the QUEST Initiative, which researchers describe as a “large prospective multicenter study of patients with any chronic health condition newly prescribed medicinal cannabis between November 2020 and December 2021.” Participants’ ages ranged between 18 and 97 years (with a mean of 51), and 62.8 percent were female.
The most common reported conditions among participants were chronic pain (69 percent), insomnia (23 percent), anxiety (22 percent) and anxiety/depression (11 percent), with half of the patients reporting more than one condition.
“We observed statistically significant, clinically meaningful improvements in overall [health-related quality of life] and fatigue over the first 3-months in patients with chronic health conditions accessing prescribed medical cannabis.”
Before beginning cannabis therapy, participants completed baseline surveys about health-related quality of life (HRQL), pain, sleep, fatigue, anxiety and depression. They were given follow-up surveys after two weeks of treatment, then once a month for three months. People were ineligible for the study if they had accessed prescribed medical cannabis during the previous four weeks.
All participants were prescribed Little Green Pharma medical cannabis oil, which contains THC and CBD dissolved in a medium-chain triglyceride (MCT) oil and was available in four formulations: a 1:20 THC-to-CBD ratio, a balanced 10:10 ratio, a THC-heavy 20:5 ratio and CBD-only (ratios listed as milligrams of THC and CBD per milliliter of oil).
Compared to their pre-treatment baseline, participants who completed three months of treatment reported improvement in overall health-related quality of life. Patients who only completed the first follow-up assessment showed less improvement compared to those who continued.
Participants in general also improved in terms of pain measures, although the improvements were greater among patients with a chronic pain diagnosis compared to those not being treated for pain.
“Anxiety, depression, and pain also improved over time, particularly for those with corresponding health conditions.”
Sleep patterns did not improve among respondents, the study found. “Analysis of 534 participants with an insomnia diagnosis…did not reveal statistically significant, or clinically meaningful change in mean Sleep T-scores over time and did not differ from patients without insomnia,” it says.
Fatigue, however, did decrease, “indicating clinically meaningful improvement.”
In terms of depression, authors wrote that “although scores shifted from moderate severity into mild severity range, the difference did not reach the 5-point threshold for clinically meaningful improvement.” But as in other categories, improvement was more marked among people diagnosed with specific conditions. Looking at 288 participants with “depression health conditions (i.e. mixed depressive and anxiety, recurrent depressive disorder, and bipolar disorder),” the study says, “respondents shifted from the severe category to moderate depression with more than 5-points difference indicating clinically meaningful improvement.”
Anxiety scores showed similar results, demonstrating significant trends of improvement over time but failing to reach the level of “clinically meaningful improvement” except among the 748 participants with diagnosed anxiety conditions. “On average,” the study found, “scores shifted from moderate/severe down to mild anxiety.”
Over the three-month period, 127 participants formally withdrew from the study, citing a variety of reasons. They included treatment not working (52 people), changing treatment (31), unwanted side-effects (30), and cannabis products being too expensive (14). But most reported at least some measure of relief.
“Within the first three months of medicinal cannabis therapy, participants reported improvements in their health-related quality of life, fatigue, and health conditions associated with anxiety, depression, and pain,” the seven-person research team said in a press release.
Despite the broadly positive findings, authors acknowledged that at least some of the reported improvements could be the result of a placebo effect.
“Our findings should be interpreted in the context of a single arm study without a control group. A systematic review of cannabis and HRQL studies revealed small effect sizes in [randomized controlled trials] and large effect sizes without control groups,” the study says. “There is a chance that observed improvements are partly due to placebo effect, with the widespread public public discussion (press and social media) on the benefits of medicinal cannabis and its interaction with the endocannabinoid system increasing patients’ expectations.”
Going forward, the study “continues to follow patients over 12-months to determine whether improvements in [patient-reported outcomes] are maintained long-term,” the report says. “In addition, further subgroup analysis will be undertaken to determine whether patients with specific conditions have better outcomes compared with others when using validated condition-specific questionnaires.”
Medical cannabis is highly regulated in Australia nationally, although changes adopted in 2016 allow access among patients with health conditions that don’t respond to conventional treatment.
In February of this year, the Australian government also rescheduled psilocybin and MDMA for narrow treatment of post-traumatic stress disorder (PTSD) and treatment-resistant depression.
“The decision acknowledges the current lack of options for patients with specific treatment-resistant mental illnesses,” Australia’s Therapeutic Goods Administration (TGA) said in a notice at the time, noting that the change meant that “psilocybin and MDMA can be used therapeutically in a controlled medical setting” starting on July 1.
As in the United States, laws in Australia can vary greatly by local jurisdiction. Lawmakers in the Legislative Assembly for the Australian Capital Territory (ACT) approved a bill last year to decriminalize low-level possession of currently illicit drugs—including psilocybin, heroin and cocaine—in the federal territory that includes the nation’s capital of Canberra.
ACT had previously decriminalized marijuana in the early 1990s, and its Assembly approved a non-commercial cannabis legalization bill that took effect in 2020, which allows adults 18 and older to possess and grow marijuana for personal use.