Depression ‘linked to teenage cannabis use’

UP TO 60,000 UK cases of adult depression could potentially be avoided if teenagers did not smoke cannabis, new research suggests.

Smoking the drug before the age of 18 is linked with an increased risk of depression and suicide in adulthood, according to a study published in journal JAMA Psychiatry.

The researchers warned cannabis was a significant public health risk, as they called for officials to make tackling use of the drug a priority. “It’s a big public health and mental health problem, we think,” co-author Professor Andrea Cipriani, from the University of Oxford, said.

“The number of people who are exposed to cannabis, especially in this vulnerable age, is very high and I think this should be a priority for public health and the mental health sector.”

The researchers analysed data from 11 studies involving more than 23,000 individuals and described it as the largest metaanalysis to date in this field.

About seven per cent of cases of adult depression may possibly not occur if teenagers stopped smoking cannabis, they found.

This means at any one time up to 60,000 cases among 18 to 34-year-olds in the UK and 400,000 in the US could be attributable to use of the drug during adolescence, they suggest.

However, a link was not found between cannabis exposure and anxiety in adulthood.

While the risk of depression is modest, the researchers said the common use of cannabis among teenagers makes it a concern. In England, about four per cent of 11 to 15-year-olds in England are estimated to have used the drug within the last month.