Those with a recorded history of cannabis use in general practice records are at a much higher risk of developing mental ill-health problems such as anxiety or depression as well as severe mental illnesses, new research shows.
The findings indicated that following the first recorded use of cannabis, patients were three times more likely to develop common mental health problems such as depression and anxiety.
In addition, they were almost seven times more likely to develop severe mental illnesses such as psychosis or schizophrenia.
“The research reaffirms the need to ensure a public health approach to recreational drug use across the UK,” said researcher Joht Singh Chandan from the University of Birmingham.
“We must continue to progress measures to improve the prevention and detection of drug use as well as implement the appropriate supportive measures in an equitable manner to prevent the secondary negative health consequences,” Chandan added.
For the study, published in the journal Psychological Medicine, the team included records from 787 GP practices around the UK gathered over 23 years between 1995 and 2018.
The researchers were able to include data from 28,218 patients who had a recorded exposure to cannabis.
These were matched to 56,208 patients who had not been using cannabis and controlled for sex, age, ethnicity, smoking status and other relevant characteristics.
The cannabis users also had much higher rates of having a recorded history of using other drugs such as heroin, cocaine and amphetamines.