A new study published in the journal Cannabis Science and Technology suggests that medical cannabis may help patients with chronic depression who do not respond to conventional treatments. The study, conducted by researchers from the LVR University Hospital in Essen, Germany, and Algea Care, a cannabis telehealth platform, followed 59 patients who received medical cannabis for six months.
Study Design and Results
The study was a naturalistic, observational, and retrospective analysis of patients who had chronic depression and were treated with medical cannabis at the LVR University Hospital between January 2019 and June 2020. The patients had failed to achieve remission with at least two different antidepressants and had a score of 14 or higher on the Patient Health Questionnaire-9 (PHQ-9), a self-report measure of depression severity.
The patients received medical cannabis products containing different ratios of tetrahydrocannabinol (THC) and cannabidiol (CBD), the two main cannabinoids in cannabis. The patients were instructed to start with a low dose and titrate up until they reached their optimal dose. The patients completed the PHQ-9 at baseline and at six months.
The results showed that the patients had a significant reduction in their PHQ-9 scores, from an average of 19.8 at baseline to 9.2 at six months. This means that the patients moved from the category of severe depression to mild depression. The researchers also reported that the patients tolerated the treatment well and had few adverse effects. The dropout rate was 15.3%, which is comparable to clinical trials of antidepressant medication.
Implications and Limitations
The study findings suggest that medical cannabis may be a viable option for patients with chronic depression who do not benefit from conventional treatments. The researchers speculated that cannabis may have a dual effect on depression, by modulating the endocannabinoid system and by enhancing the effects of serotonin, a neurotransmitter involved in mood regulation.
However, the study also had some limitations that need to be addressed in future research. The study was not a randomized controlled trial, so it could not establish a causal relationship between medical cannabis and depression improvement. The study also lacked a control group, so it could not rule out the effects of placebo or other factors. The study relied on self-report measures, which may be subject to bias or inaccuracy. The study did not assess the long-term effects of medical cannabis on depression or other outcomes, such as quality of life, functioning, or cannabis use disorder.
Future Directions and Recommendations
The researchers concluded that their study provides preliminary evidence for the efficacy and safety of medical cannabis in treating chronic depression. They called for more prospective cohort studies and randomized controlled trials to confirm their findings and to derive valid recommendations for the use of medical cannabis in this population. They also suggested that more research is needed to identify the optimal doses, formulations, and delivery methods of medical cannabis for depression.
The researchers also highlighted the importance of providing adequate education, guidance, and monitoring for patients who use medical cannabis for depression. They recommended that patients consult with their doctors before starting or changing their cannabis regimen, and that they use cannabis products from licensed and regulated sources. They also advised that patients be aware of the potential risks and benefits of medical cannabis, and that they seek help if they experience any adverse effects or signs of cannabis use disorder.
