“We aimed at clarifying the strength and consistency of the association between cannabis use disorder and suicide attempts in bipolar disorder.

We could not perform a meta-analysis exploring the longitudinal association between cannabis use disorder and suicide attempts, due to the lack of suitable data.

The current evidence highlights a weak association between cannabis use disorder and suicidal attempts in bipolar disorder.

Due to the cross-sectional design of included studies, causal inferences could not be explored.”

https://www.ncbi.nlm.nih.gov/pubmed/31121199

https://www.sciencedirect.com/science/article/pii/S014976341830993X?via%3Dihub