The number of marijuana-related ER visits made by teens and young adults more than quadrupled at one Colorado hospital after the state legalized the drug, a new report finds.
Researchers analyzed information from people ages 13 to 21 who visited the emergency room at Children's Hospital Colorado or one its satellite urgent-care centers between January 2005 and June 2015.
The investigators found that the number of yearly ER visits that involved teens and young adults who had recently used marijuana increased from 146 visits in 2005 to 639 visits in 2014. The overall rate of these visits increased from about one per 1,000 people in this age group in 2009 to four per 1,000 people in the same age group in 2015.
In Colorado, the commercial production and distribution of marijuanafor medical use was legalized in 2010, and the recreational use of marijuana was legalized in 2014.
Previous research using data from the entire United States has suggested that marijuana's legalization has not significantly affected teen marijuana use, with about the same percent of adolescents using the drug before and after legalization.
But based on the new findings, the researchers said they suspect that national surveys do not entirely reflect the impact of legalization at a more local level.
"The state-level effect of marijuana legalization on adolescent use has only begun to be evaluated," Dr. George Sam Wang, an author of the report and an assistant professor of pediatrics at the University of Colorado Anschutz Medical Campus, said in a statement .
The report additionally found that 66 percent of the teens and young adults who went to the ER for a marijuana-related reason were also evaluated by a psychiatrist while they were there. This suggests that the individuals had symptoms of a mental health condition, the report said.
Due to that finding, doctors may consider screening teens for mental health conditions if those teens have recently used marijuana, Wang told Live Science.
The researchers noted that they could not determine from their data exactly how each patient's marijuana use led to an ER visit. For example, some patients may been diagnosed with marijuana dependence , while others had marijuana-related injuries. Some of the patients could have been at the ER for some other reason, but tested positive for marijuana during a urine drug screen, the report said.
The report will be presented on Monday (May 8) at the Pediatric Academic Societies Meeting in San Francisco.
Original article on Live Science .