Assessing causality in associations between cannabis use and schizophrenia risk: a two-sample Mendelian randomization study

09 Nov 2016S. H. Gag, H. J. Jones, S. Burgess, J. Bowden, G. Davey Smith, S. Zammit and M. R. Munafò

Our results provide some that cannabis initiation increases the risk of schizophrenia, although the size of the causal estimate is small. We find stronger evidence that schizophrenia risk predicts cannabis initiation, possibly as genetic instruments for schizophrenia are stronger than for cannabis initiation.

Case-control study
1 effect
150064 subjects

Reported Outcomes


Marijuana Herb risk & protective factor
Minor Risk Factor Marijuana

Schizophrenia Brain outcome
Minor increase risk of Schizophrenia
Brain system

High evidence