Cannabis-related ED visits increase 3-fold after legalization in Colorado

Following the legalization of recreational marijuana in Colorado, there has been a significant increase in cannabis-related ED visits, driven largely by inhaled cannabis, according to a study published in the Annals of Internal Medicine. Edible cannabis was also linked to more ED visits and acute psychiatric visits than expected, according to the report.

“Despite edible cannabis products accounting for a small proportion of the total number of cannabis products sold and used, they frequently contribute to ED visits and may be more toxic than inhalable products,” Andrew A. Monte, MD, PhD, from the University of Colorado School of Medicine, and colleagues wrote.

Researchers conducted a chart review of patients aged 18 years or older at the UCHealth University of Colorado Hospital ED from Jan. 1, 2012 through Dec. 31, 2016. They reviewed visit with ICD-9-CM or ICD-10-CM codes associated with cannabis use, and determined the route of cannabis exposure, the cannabis dose and symptoms.

During the study period, there was a 3-fold increase in cannabis-related ED visits. A total of 9,973 visits were coded with either ICD-9-CM or ICD-10-CM codes for cannabis use and of those, 2,567(25.7%) were considered at least partially attributable to cannabis use. The route of exposure was available for 2,432 (94.7%) of visits, with 238 (9.3%) attributed to edible ingestion and 2,194 to inhalation. The 135 visits where route of exposure was unavailable were assumed to be inhalation. The most common reasons for ED visits were gastrointestinal symptoms (n = 778; 30.7%), intoxication (n = 762; 29.7%), and psychiatric symptoms (n = 633; 24.7%).

Cannabinoid hyperemesis syndrome was more likely in visits associated with inhaled cannabis than edible cannabis (18% vs. 8.4%). Edible cannabis was more likely to be the cause in visits related to psychiatric symptoms (18% vs. 10.9%), intoxication (48% vs. 28%), and cardiovascular symptoms (8% vs. 3.1%).

Although edible cannabis only accounts for 0.32% of cannabis sales in Colorado during the study period, it accounted for 10.7% of ED visits.

“Research is needed not only to rigorously ascertain evidence about potential beneficial effects of cannabis but also to carefully characterize its potential negative effects,” said Nora D. Volkow, MD, and Ruben Baler, PhD, of the National Institute on Drug Abuse in an editorial accompanying the study. “These findings also underscore the urgent need for greater oversight of manufacturing practices, labeling standards, and quality control of cannabis products marketed to the public.”– by Erin Michael

References:

Monte AA, et al. Ann Intern Med. 2019;doi:10.7326/M18-2809.

Volkow ND, et al. Ann Intern Med. 2019;doi:10.7326/M19-0542.

Disclosures: Monte reports grants from the Colorado Department of Public Health and Environment during the conduct of the study and also sits on the Colorado Retail Marijuana Public Health Advisory Committee. Please see the study for all other authors’ relevant financial disclosures.