Medicinal cannabis linked to long-term health benefits

Patients prescribed medicinal cannabis maintain improvements in overall health-related quality of life (HRQL), fatigue, sleep disturbance and more across a one-year period, according to a study published in the journal PLOS One.

Research into the therapeutic benefits of medicinal cannabis has increased since the discovery of the analgesic properties in cannabis plant compounds. As part of a multicentre prospective study called the QUEST (QUality of life Evaluation STudy) Initiative, Margaret-Ann Tait from The University of Sydney and colleagues recruited adult patients with any chronic health condition newly prescribed medicinal cannabis oil between November 2020 and December 2021. The researchers gathered 12-month follow-up data to determine if previously reported improvements at three months would be maintained long term.

The team found that improvements in overall HRQL reported at three months were maintained over a 12-month period. People with chronic health conditions reported improvements in fatigue, pain and sleep; patients with anxiety, depression, insomnia or chronic pain diagnoses also showed improvements in condition-specific symptoms over 12 months. Patients treated for generalised anxiety, chronic pain, insomnia and PTSD all showed improvements in HRQL. Participants with movement disorders had improved HRQL but no significant improvements in upper extremity function scores.

According to the researchers, the study was large enough to assess patients across a wide range of chronic conditions and socio-demographics in a real-world setting, with 2353 participants completing baseline assessments as well as at least one follow-up questionnaire. And while the lack of a control group meant it was not possible to confidently attribute changes over time to medicinal cannabis, the results suggest that prescribing medicinal cannabis to patients with chronic health conditions may improve pain, fatigue, insomnia, anxiety, depression and overall HRQL in both the short and the long term.

The news comes shortly after scientists at the University of South Australia (UniSA) announced a way to improve the effectiveness of cannabidiol (CBD) — a non-psychoactive compound found in the cannabis plant — to treat epilepsy, multiple sclerosis and other neurodegenerative diseases, which they have reported in the International Journal of Molecular Sciences.

CBD is widely prescribed for its analgesic, anti-inflammatory and neuroprotective properties, but its clinical applications to date have been limited by its poor water solubility and absorption in the human body. By developing a phospholipid complex — a class of lipids that contain phosphorus — the researchers increased the solubility of CBD by up to six times and improved its absorption in the gastrointestinal tract.

The research team identified the optimal phospholipid composition to form nanosized CBD-PLC particles. Compared to pure CBD, the phospholipid complex improved dissolution rates from 0% to 67.1% within three hours, demonstrating a significant enhancement in drug release. In cellular uptake studies, CBD-PLC exhibited 32.7% higher permeability than unmodified CBD, for greater absorption through the intestinal wall.

Another advantage of this new delivery system is its stability. Traditional CBD formulations degrade over time when exposed to heat, light or oxygen, reducing potency and shelf life. However, testing over 12 months showed that CBD-PLC retained its performance under varied storage conditions, making it a more reliable option for pharmaceutical applications.

“Improved bioavailability means that lower doses can achieve the same therapeutic effect, potentially reducing side effects and making treatment more cost-effective,” said PhD candidate Thabata Muta, first author on the study.

Image caption: Patient using Little Green Pharma cannabis oil medications during The QUEST Initiative study. Image courtesy Jake Barker (owned by LGP) under CC-BY 4.0.