Cannabinoid Hyperemesis Syndrome, 2016 to 2022

Importance Cannabinoid hyperemesis syndrome (CHS), ie, recurrent emesis from chronic cannabis use, is increasingly observed in emergency departments (EDs), yet population-level estimates and sociodemographic correlates remain underexplored. Objective To estimate CHS prevalence in US EDs, assess trends from 2016 to 2022, and examine sociodemographic associations. Design, Setting, and Participants This cross-sectional study, using data from the Nationwide Emergency Department Sample (approximately 85% of annual US ED visits) examined patients aged 12 years and older. Patients with ED visits related to pregnancy, gastroparesis, or chemotherapy were excluded. Main Outcomes and Measures ED visits were grouped into 4 categories. Primary outcome was comparative temporal trends between each of the 4 categories: (1) no cannabis use or cyclic vomiting syndrome (CVS); (2) cannabis-related condition only; (3) CVS only; and (4) both cannabis-related condition and CVS (CHS proxy). Restricted cubic splines modeled temporal trends; multinomial logistic regression identified sociodemographic factors associated with CHS. Results The analytic sample included 188 610 906 unweighted visits (806 million weighted); 433 251 323 (54.4%) were female; mean (SD) age, 47.9 years (95% CI, 47.8-48.1 years). CHS increased from 4.4 per 100 000 visits, peaked at 33.1 in quarter 2 2020, and remained elevated at 22.3 in 2022; concurrently, CVS-only declined from 300 to 186 per 100 000 visits. Females had lower CHS risk (RRR, 0.92; 95% CI, 0.88-0.95) as did patients in the South vs Northeast (RRR, 0.46; 95% CI, 0.40-0.53); risk was highest at ages 18 to 25 years (RRR, 3.59; 95% CI, 3.38-3.81) and 26 to 35 years (RRR, 2.26; 95% CI, 2.14-2.40). Conclusions And Relevance In this cross-sectional study of US ED visits, CHS prevalence increased sharply during the COVID-19 pandemic and remained elevated. The findings highlight the need for continued vigilance and refinements to the clinical recognition of CHS.