Published in the journal Psychiatry Research in July 2022, this was a retrospective study focused on the effectiveness of cannabis for anxiety and depression. "This study provides some evidence to support the effectiveness of medical cannabis as a treatment for anxiety and depression."
The study included over 7,000 patients from a single clinic in Canada. They completed standardized, validated questionnaires for anxiety (GAD-7) and depression (PHQ-9) at their first visit and at least once after that. The minimum age was 18 and the average age was almost 50 years; just over half were female.
Overall, the study showed patients report that cannabis helps them to manage anxiety and depression, with those that specifically looked for cannabis showing better results.
"There were statistically significant improvements between baseline and follow-up scores for both the GAD-7 and PHQ-9, with larger improvements seen for patients who were actively seeking medical cannabis to treat anxiety or depression."
"From 12 months on, those reporting anxiety had an average decrease in GAD-7 scores that was greater than the minimum clinically important difference of 4, and the same was seen for patients reporting depression from 18 months on, with the average decrease in PHQ-9 scores more than the MCID minimum clinically important difference of 5."
An abstract of the study is here at ScienceDirect.com.