Skunk use associated with increased risk of developing psychosis
People who smoke skunk are 18 times more likely to develop psychosis than those who smoke milder forms of cannabis, according to a study conducted at the Institute of Psychiatry and presented at the Annual Meeting of the Royal College of Psychiatrists this week.
As part of the Genetics and Psychosis (GAP) study led by Prof Robin Murray, Dr Marta Di Forti compared the pattern of cannabis use in two groups, one containing 112 people with first-episode psychosis and the other containing 75 people without mental illness. Both groups were from South East London.
The study found that those people with first-episode psychosis were:
- 2 times more likely to have used cannabis for a longer time
- 3 times more likely to have used it on a daily basis
- 18 times more likely to use skunk
The finding that the risk of developing psychosis is increased with the frequency of cannabis use, and with the strength of the cannabis used, led Dr Di Forti to urge psychiatrists to question their patients with regards to cannabis use in a more detailed way. "We should have more data on cannabis exposure. We should take a cannabis history in a more detailed way like we do when we take a history of cigarettes smoking to establish risk of lung cancer”.
