Trends in Cannabis-Related Hospitalizations in Arizona From 2016 to 2021 and Associations With Mental Health-Related Hospitalizations

Abstract

Objective: The purpose of this study was to examine trends in cannabis-related hospital visits in Arizona from 2016 to 2021 and associations with hospital visits for a mental health condition.

Method: Data were emergency department and inpatient hospital discharge records from all Arizona licensed hospitals from 2016 to 2021. Records comprised 18,758,614 hospital visits. Cannabis-related visits were defined by International Classification of Diseases (ICD) diagnostic codes for cannabis use (unspecified use, abuse, dependence) or poisoning. Mental health visits were defined by ICD diagnostic codes for mental health conditions.

Results: The rate of cannabis-related hospital visits increased from 1,301.50 per 100,000 visits in 2016 to 1,565.54 per 100,000 visits in 2021, a 20% increase. The increase was larger for visits by adolescents and older adults ages 65+: 63.94% and 84.45%, respectively. Cannabis-related visits were 7.75 (95% CI [7.69, 7.81]) times as likely as visits unrelated to cannabis to have a mental health condition as the primary diagnosis from 2016 to 2021 and were 2.32 (95% CI [2.30, 2.34]) times as likely after adjustment for covariates, including alcohol and other substance-related diagnoses. The association between cannabis-related visits and mental health-related visits increased each year, particularly for older adults ages 65+.

Conclusions: The rate of cannabis-related hospital visits is increasing, as is the cannabis-related risk of a hospital visit for a mental health condition. The increases are especially pronounced among hospital visits by older adults (ages 65+), highlighting the need for prevention and intervention in this under-recognized at-risk group.