Differential effects of cannabis exposure during early versus later adolescence on the expression of psychosis in homeless and precariously housed adults.
Progress in Neuro-psychopharmacology and Biological Psychiatry September 2, 2020 K. Gicas, Alex Y T Cheng, W. Panenka et al.
In a sample of 437 adults recruited from single-room occupancy hotels in Vancouver's Downtown Eastside, early cannabis exposure (by age 15) was associated with a slightly increased risk of developing substance-induced psychosis, while later first use (after age 15) was linked to a higher risk of schizophrenia or schizoaffective disorder. No differences in neurocognitive function were found between groups, though brain structure differences appeared in the lateral orbitofrontal cortex and white matter tracts. The findings suggest that early cannabis exposure in this high-risk population may contribute to drug-associated psychoses, possibly through altered brain development.