Demonstrators smoke marijuana during the "4/20 Santiago" rally in front of the La Moneda presidential palace in Santiago, Chile, on April 20, 2017. (Claudio Reyes, AFP/Getty Images)

Teen ER visits linked to marijuana are climbing in legal era, Colorado doctor finds

The number of teenagers going to the emergency room at Children’s Hospital Colorado for what appeared to be marijuana-related reasons increased significantly after legalization, a new study by a Children’s doctor found.

Dr. Sam Wang said his study contrasts with surveys that suggest youth marijuana use in Colorado has not increased since legalization. But he said the study also has its limitations, meaning it adds important data to the debate over legalization but is not the final word on it.

“Everything has to be taken with a grain of salt,” he said. “I don’t think one database is perfect. But this is just another way to look at the data that shows more teenagers are coming to the ER.”

Wang gathered data on marijuana-related emergency room visits to Children’s Hospital and its satellite clinics for teenagers and young adults up to age 21 by looking at two measures.

The first is a hospital billing code used on a patient’s chart when marijuana is involved in a patient’s medical problem. Wang said marijuana might not be the primary reason the patient went to the hospital, but marijuana usually has to be sufficiently connected to the patient’s symptoms to warrant the code being written down. He said it is unlikely the code would be put on a patient’s record for marijuana use unrelated to the symptoms.

The second measure is when a patient has a urine drug screen that comes back positive for marijuana. Such drug screens occur when a patient ingested an unknown substance or before a patient undergoes a psychiatric evaluation.

Collecting those numbers, Wang said he found that 106 teens and young adults visited Children’s emergency room for marijuana-related reasons in 2005 and that number jumped to 631 in 2014. The rate of those visits increased as well — though by 2015 marijuana still accounted for only four out of every 1,000 visits.

Perhaps most worrisome, Wang said he found that the number of kids and young adults in the emergency room for marijuana-related reasons and who subsequently needed a psychiatric evaluation also increased rapidly — from 65 in 2005 to 442 in 2014. Wang said patients who receive psychiatric evaluations may be severely intoxicated or may have tried to commit suicide or talked about committing suicide.

Colorado’s medical marijuana dispensaries began opening in large numbers in 2010, and Colorado voters legalized the sale and possession of limited amounts of marijuana for any purpose in 2012, with recreational stores opening on Jan. 1, 2014.

“Looking at the trend, it is definitely significant,” Wang said.

Wang’s study results were first presented earlier this month at an academic conference in San Francisco. He said he hopes to publish the findings in a journal later this year.

The findings add another layer to understanding how marijuana legalization has affected kids. Thus far, much of the survey data of Colorado teens has suggested little impact. Both state and federal surveys have found that Colorado teen marijuana use rates — though among the highest in the country — have remained flat since legalization.

“Our worst nightmares haven’t materialized,” Colorado Gov. John Hickenlooper said earlier this year of legalization.

In a previous study, though, Wang found that the number of young kids going to the emergency room for accidental marijuana exposure increased following legalization. He said his new study shows there is still more to learn about why a subset of kids is ending up in the hospital.

“We’re finding things contrary to other national survey data,” he said. “And so we feel like, to really better understand the impact in this particular population, I think we need to use multiple data sources.”

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