Changes in patient health questionnaire (PHQ-9) scores in adults with medical authorization for cannabis

Abstract

Background: Legal access to medical cannabis is increasing worldwide. Despite this, there is a lack of evidence surrounding its efficacy on mental health outcomes, particularly, on depression. This study assesses the effect of medical cannabis on Patient Health Questionnaire (PHQ-9) scores in adult patients between 2014 and 2019 in Ontario and Alberta, Canada. Methods: An observational cohort study of medically authorized cannabis patients in Ontario and Alberta. Overall change in PHQ-9 scores from baseline to follow-up were evaluated (mean change) over a time period of up to 3.2 years. Results: 37,338 patients from the cohort had an initial PHQ-9 score recorded with 5103 (13.7%) patients having follow-up PHQ-9 scores. The average age was 54 yrs. (SD 15.7), 46% male, 50% noted depression at baseline. The average PHQ-9 score at baseline was 10.5 (SD 6.9), following a median follow-up time of 196 days (IQR: 77-451) the average final PHQ-9 score was 10.3 (SD 6.8) with a mean change of − 0.20 (95% CI: − 0.26, − 0.14, p-value < 0.0001). Overall, 4855 (95.1%) had no clinically significant change in their PHQ-9 score following medical cannabis use while 172 (3.4%) reported improvement and 76 (1.5%) reported worsening of their depression symptoms. Conclusions: Although the majority showed no clinically important changes in PHQ-9 scores, a number of patients showed improvement or deteriorations in PHQ-9 scores. Future studies should focus on the parallel use of screening questionnaires to control for PHQ-9 sensitivity and to explore potential factors that may have attributed to the improvement in scores pre-and post-3-6 month time period.

The longitudinal association between depression, anxiety symptoms and HIV outcomes, and the modifying effect of alcohol dependence among ART clients with hazardous alcohol use in Vietnam

“…Depression and anxiety symptoms were rescaled so that the reported estimates of association reflect the change in outcome associated with a 5‐unit change in the continuously measured PHQ‐9 or GAD‐7 score. We performed this rescaling because a 1‐unit change in each score is not clinically meaningful, whereas a 5‐unit change is considered potentially clinically significant, implying that a participant has moved from one level of severity to the next [67,68]. This rescaling method has been used in other studies using continuous measures of depression and anxiety symptoms [69,70].…”

Description and Disposition of Patients With Cancer Accessing a Novel, Pharmacist-Led Cannabis Consultation Service

“…Similar challenges with measuring effects of MC with standardized symptom scales have been reported. 58…”

“…Similar challenges with measuring effects of MC with standardized symptom scales have been reported. 58 There are opportunities for the CCS to engage in further research to better understand the role of PDCs in cancer supportive care. Engaging patients in the research process will help to better meet patient needs while propelling knowledge translation for use of PDCs in the oncology setting.…”

Impact of adalimumab on disease burden in moderate-to-severe ulcerative colitis patients: The one-year, real-world UCanADA study

“…Significant changes from baseline were observed at week 8, which were maintained at week 52 and were slightly higher for the completers population ( P = 0.010). Despite this improvement, these scores may be interpreted as a remaining mild depression in patients[ 10 ] and not necessarily a clinically meaningful change[ 52 - 54 ], which indicates a potential relevance to offer psychological support to this population[ 7 , 55 ]. In the present observational study, while patients who had a preliminary failure to biologics were excluded, patients with secondary failures were included, which may have led to the inclusion of patients with greater psychological burden than biologic-naïve patients.…”