Abstract
Amphetamine type stimulants (ATS) and ketamine have emerged as major drug problems in China, and chronic extensive exposure to these substances frequently co-occurs with psychiatric symptoms. This study compares the psychiatric symptoms of patients reporting ATS use only, ATS and ketamine use, or ketamine use only who were admitted to an inpatient psychiatry ward in Wuhan, China between 2010 and 2011. Data on 375 study participants collected during their ward admission and extracted from their clinical records included their socio-demographics, scores on the Brief Psychiatric Rating Scale (BPRS), and urine toxicology screens. RESULTS: The ketamine-only group had significantly lower total BPRS scores and significantly lower scores on Thinking Disorder, Activity, and Hostility-Suspicion BPRS subscales than the ATS-only and ATS + ketamine groups (p < 0.001 for all comparisons). The ketamine-only group also had significantly higher scores on the subscales of Anxiety-Depression and Anergia. The ATS-only group had significantly higher scores on subscales of Thinking Disorder, Activity, and Hostility-Suspicion and significantly lower scores on Anxiety-Depression and Anergia subscales than the ketamine-only and ATS + ketamine groups (p < 0.001 for all comparisons). A K-means cluster method identified three distinct clusters of patients based on the similarities of their BPRS subscale profiles, and the identified clusters differed markedly on the proportions of participants reporting different primary drugs of abuse. The study findings suggest that ketamine and ATS users present with different profiles of psychiatric symptoms at admission to inpatient treatment.