CPA Special Issue Summary

Bourque (2017 ) investigated: 1) if impairments in cognitive development due to cannabis misuse may exacerbate psychotic experiences and 2) the comorbidity of anxiety and depression symptoms with psychotic experiences and whether they lead to psychotic experiences in adolescents.

4,000 Montreal adolescents survey 8% reported persistent psychotic experiences, frequency of Cannabis use and psychotic experiences increase with age across the population

Found that only “inhibitory control” was the only cognitive function to be impaired.

Leadbeater, Thompson, Ames, Merrin, Sukhawathanakul & Sturggess (2017) examined the relationship between chronic use and academic performance and economic outcomes among youth.

They found: 29% Abstainers, 27% Occasional users, 14% Decreasers, 20% Increasers, and 11% Chronic users.

Increasers and Chronic users had more externalizing problems as youth and young adults
Decreasers had more depressive symptoms and conduct problems in adolescence but not young adulthood
Occasional users showed higher levels of depressive symptoms and externalizing behavior than decreasers in young adulthood.

Flemming & McKiernan (2017) did focus groups to find that youth were looking for cannabis information on both benefits and problems from use.

Daniels (2017) examined prenatal cannabis use, but found that there is no evidence of detrimental effect of occasional cannabis use by pregnant women. She also reports that cannabis use has benefits for the treatment of Hypermesis Gravidarum (HG) which involves “nonstop vomiting and nausea leading to weight loss and dehydration” (p. 14).

Goldstein & Thompson (2017) examined cannabis use in the post secondary context, showing that it is the most commonly used substance (17% of students).

Thiessen, Crosby & Walsh (2017) report on the benefits of cannabis use as a substitute for harder drugs, like cocaine and opiates.
Studies from California and Brazil support the positive substitute benefits.