Schizophrenic Genes may Increase Cannabis Use, Quantity

Marijuana might make you delusional, but could cannabis use be linked to schizophrenia?

A new study published in the journal Molecular Psychiatry examines a potential link between cannabis use and schizophrenia, based on common genes. However, it has remained unclear whether the association is due to cannabis use directly increasing risk of the health issue.

"Studies have consistently shown a link between cannabis use and schizophrenia," said lead study author from King's, Robert Power, via a news release. "We wanted to explore whether this is because of a direct cause and effect, or whether there may be shared genes which predispose individuals to both cannabis use and schizophrenia."

As cannabis remains the most widely used illicit drug throughout the world, its use tends to be higher among those with schizophrenic tendencies--a health issue that affects about 1 in 100 people. In fact, study findings suggest that cannabis use can more than double the risk of the development of this health issue.

In the study, researchers examined 2,082 healthy individuals. Of these participants, 1,011 had used cannabis. Each individual's ‘genetic risk profile' was measured based on the number of genes related to the disorder that the individual carried.

Study results showed that those who were genetically pre-disposed to schizophrenia were more likely to use cannabis and in greater quantities than those who did not possess schizophrenia risk genes.

"We know that cannabis increases the risk of schizophrenia. Our study certainly does not rule this out, but it suggests that there is likely to be an association in the other direction as well - that a pre-disposition to schizophrenia also increases your likelihood of cannabis use," the researchers added. 

"Our study highlights the complex interactions between genes and environments when we talk about cannabis as a risk factor for schizophrenia. Certain environmental risks, such as cannabis use, may be more likely given an individual's innate behaviour and personality, itself influenced by their genetic make-up. This is an important finding to consider when calculating the economic and health impact of cannabis."

To learn more about symptoms associated with this health issue, including delusions and auditory hallucinations, click here.