Clinical Characteristics and Symptom Severity in Patients with Gambling Disorder in Japan.

Background and aims: Japan has a unique gambling environment compared with other countries: pachinko and pachislot dominate the gambling market and are easily accessible. We investigated the clinical characteristics of treatment-seeking Japanese patients with gambling disorder (GD), focusing on factors related to GD severity.

Methods: This cross-sectional analysis used data from the Japan Collaborative Clinical Study on Gambling Disorder (JaCCS-G), a multicenter collaborative prospective study evaluating the effectiveness of outpatient treatment for GD. Twenty medical institutions with outpatient gambling clinics participated in this study. Individuals with GD who visited participating facilities and were diagnosed with GD based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, were included. Semi-structured interviews were conducted to assess gambling behavior and psychiatric comorbidities. We administered the Gambling Symptom Assessment Scale to assess gambling symptom severity, the Gambling Related Cognitions Scale to assess irrational thoughts in GD, and the Barratt Impulsiveness Scale (11th version) (BIS-11) to assess impulsivity.

Results: A total of 202 patients with GD participated in the JACCS-G. Pachinko was the most common type of gambling seen in patients with GD, followed by pachislot and horse racing. BIS-11 total score significantly differed among patients with mild, moderate, and severe GD. Antisocial personality disorder (ASPD) was associated with GD severity.

Discussion and conclusions: These results reflect the unique gambling environment in Japan, where pachinko is the most accessible and prevalent form of gambling. Assessing GD severity may help identify individuals with heightened impulsivity or ASPD, enabling more targeted interventions and improved treatment strategies. (249 words).