Teens who use weed before age 15 have more trouble later, a study finds

"The new study used data from the Quebec Longitudinal Study of Child Development. Researchers in Montreal, Canada, have been following more than 1,500 kids since birth into young adulthood to understand the factors that influence their development and their health. Among the various aspects of the kids' lives and habits scientists have recorded is cannabis use between ages 12 and 17."

"The researchers found that a majority of teens 60% didn't use cannabis in adolescence. Among the remaining 40%, half started using cannabis in their late teens and by the time they turned 17, they used the drug infrequently less than once a month. The remaining 20% started using marijuana before they turned 15, and by age 17, they were using it at least once a month."

""The risk is concentrated among those who start early and use frequently," says psychologist and the study's main author Massimiliano Orri at McGill University. Early, frequent cannabis users had a 51% higher chance of seeking care for mental health problems in young adulthood compared to those who didn't use the drug. And that risk was calculated after controlling for a range of confounding factors that are known to influence health, like bullying or lack of parental involvement. Similarly"

Data come from the Quebec Longitudinal Study of Child Development tracking over 1,500 children from birth into young adulthood, with cannabis use recorded between ages 12 and 17. Sixty percent did not use cannabis during adolescence. Of the remaining 40%, half initiated in late teens and used less than once monthly by 17, while 20% initiated before 15 and were using at least once monthly by 17. Early, frequent adolescent users were more likely to seek health care for both mental and physical conditions in young adulthood. The mental health care risk was 51% higher after adjustment for confounders such as bullying and parental involvement.

Read at www.npr.org