Evaluating expectancies: Do community-recruited adults believe that cannabis is an effective stress reliever?

There is growing interest in using cannabis or specific cannabinoids (e.g., THC, CBD) as therapeutic agents for various stress-related psychiatric disorders (e.g., PTSD, anxiety). While beliefs about a drug, such as expecting to feel a certain way, have strong influences over the actual effects experienced by individuals, they are rarely evaluated in clinical research. In the present exploratory report, we sought to (1) evaluate the extent to which individuals believe that cannabis relieves stress, and (2) examine whether individual characteristics (i.e., age, sex, psychiatric illness, cannabis use frequency) are related to these beliefs. A sample of 234 adults (54.7% female; Mean age=31.37, SD=11.03, 19-69 years old) from the Halifax Regional Municipality community took part in a brief telephone screening interview to assess their eligibility for a larger study (in progress). Information was gathered about the frequency of current (i.e., past month) cannabis use (days per week), the presence of current psychiatric disorder(s) ("yes"/"no"), and the extent to which they believed that cannabis was an effective stress reliever (rating scale from 1 (“not at all”) to 10 (“extremely”)). Subjects reported a mean belief rating of 6.39 (SD=2.26). A multiple regression analysis was run to evaluate whether the belief that cannabis relieves stress was related to age, sex, psychiatric illness, and frequency of current cannabis use. Overall, the model significantly predicted cannabis belief ratings (p<.001, adjusted R2=.17). Among all variables, only frequency of cannabis use contributed significantly to this prediction (B=.544, 95% CI: [.387, .701], p<.001). In general, the present sample of community-recruited adults believed that cannabis was somewhat effective at relieving stress. Additionally, cannabis use frequency was the only variable that predicted the strength of this belief, such that more frequent use was associated with higher belief ratings. This is consistent with prior research indicating that heavier cannabis use is linked to positive cannabis expectancies. Given that stimulus expectancies influence substance-related responses, such findings would further the case for evaluating and controlling for these expectancies in clinical work with cannabis for stress-related conditions. Indeed, clinical cannabis research evaluating samples of heavy or frequent cannabis users may be subject to bias due to higher positive expectancies.