Characteristics of Synthetic Cannabinoid and Cannabis Users Admitted to a Psychiatric Hospital: A Comparative Study

Background: Psychotic and affective exacerbations associated with synthetic cannabinoid (SC) use are becoming an emerging concern in psychiatric hospitals. However, data are lacking regarding whether clinical manifestations of SC use differ from those associated with cannabis use.

Objective: Our aim was to explore the unique profile of SC users admitted to a mental health center in terms of demographic, clinical, and physiologic variables in comparison to cannabis users.

Methods: We retrieved retrospective data of patients admitted to a mental health center between October 2007 and May 2014 who self-reported recent use of SC (n = 60) and patients who were cannabis users (positive carboxy-tetrahydrocannabinol urine test at admission) without a history of SC use (n = 163). Clinical measures included hospitalization length, number of previous hospitalizations, Positive and Negative Syndrome Scale (PANSS) scores, psychiatric status at admission, and relevant physiologic and laboratory parameters.

Results: Hospitalized SC users were younger than hospitalized cannabis users (n = 163) (30.46 ± 7.83 years versus 34.67 ± 10.07 years, U223 = 3,781.5, P = .009, respectively). SC patients had longer hospitalizations compared to cannabis users (43.45 ± 54.02 days versus 22.91 ± 31.36 days, U219 = 5,701.5, P = .005, respectively), had more previous hospitalizations (3.73 ± 5.05 versus 1.98 ± 5.12, U223 = 6,284, P < .001, respectively), and were more likely to be hospitalized by criminal court order (36.7% [n = 22] versus 19.9% [n = 32], χ22 = 7.136, P = .028, respectively). SC patients presented with a more severe clinical picture manifested by higher total PANSS scores (82.53 ± 23.05 versus 69.98 ± 19.94, t91 = −2.696, P = .008) in a subset of patients with PANSS scores assessed within a week from admission (n = 30 in the SC group and n = 63 in the cannabis group). No differences were found in physiologic or laboratory measures on admission between the SC and cannabis groups.

Conclusions: Patients admitted following use of SC are generally younger males who have higher severity of psychotic symptoms at admission, are more likely to be admitted by criminal court order, and require longer hospitalization periods in comparison to cannabis users.