Effects of Cannabis Use on Human Brain Structure in Psychosis: A Systematic Review Combining In Vivo Structural Neuroimaging and Post Mortem Studies
Charlotte Rapp, Hilal Bugra, Anita Riecher-Rossler, Corinne Tamagni and Stefan Borgwardt
Pages 5070-5080 (11)
It is unclear yet whether cannabis use is a moderating or causal factor contributing to grey matter alterations in schizophrenia
and the development of psychotic symptoms. We therefore systematically reviewed structural brain imaging and post mortem studies addressing
the effects of cannabis use on brain structure in psychosis. Studies with schizophrenia (SCZ) and first episode psychosis (FEP)
patients as well as individuals at genetic (GHR) or clinical high risk for psychosis (ARMS) were included. We identified 15 structural
magnetic resonance imaging (MRI) (12 cross sectional / 3 longitudinal) and 4 post mortem studies. The total number of subjects encompassed
601 schizophrenia or first episode psychosis patients, 255 individuals at clinical or genetic high risk for psychosis and 397 healthy
controls. We found evidence for consistent brain structural abnormalities in cannabinoid 1 (CB1) receptor enhanced brain areas as the
cingulate and prefrontal cortices and the cerebellum. As these effects have not consistently been reported in studies examining nonpsychotic
and healthy samples, psychosis patients and subjects at risk for psychosis might be particularly vulnerable to brain volume loss
due to cannabis exposure.
Cannabis, post-mortem, neuroimaging, At-risk mental state (ARMS), psychosis, magnetic resonance imaging (MRI)
Department of Psychiatry, University of Basel, c/o University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland.