Implementing At-Risk Mental State Services in a Japanese Clinical Setting

Presentation First Author: 
Kazunori Matsumoto

Background: The concept of at-risk mental state (ARMS) is valuable for identifying individuals in a putative prodromal state of psychosis and for reducing conversion risk. However, since most evidence is derived from longitudinal observations in Western countries, observations from the rest of the world are imperative if the concept is to be generalized to various clinical settings.Methods: A naturalistic longitudinal study was conducted at a specialized early psychosis clinic at a university hospital in Sendai, Japan. Individuals with ARMS (n = 106) were recruited and followed on a case-by-case treatment basis.Results: Although the baseline characteristics of the participants generally replicated previous studies, no one had a history of substance use. Two-thirds of the participants were psychiatrist referrals; 83 were followed for at least 1 year, with a mean follow-up of 2.4 years. One-third received antipsychotic medication during follow-up and 14 developed psychosis. The estimated cumulative transition rate was 11.1% at 12, 15.4% at 24, and 17.5% at 30 months. Compared to non-converters, converters showed more severe attenuated psychotic symptoms. Discussions: This study replicated previous major Western longitudinal studies, though risk factors associated with substance use appear much lower than in studies from Western countries. Although many patients with ARMS directly visit psychiatrists under universal health insurance coverage, overdiagnosis of schizophrenia and overprescription of antipsychotics are concerns. Improving education for psychiatrists and implementing an appropriate clinical service system is necessary in Japanese clinical settings to address this population's needs.

Conference Name: 
Presentation Date: 
January, 2015
Additional Authors: 
Noriyuki Ohmuro - Masahiro Katsura - Chika Obara - Tatsuro Kikuchi - Yumiko Hamaie - Emi Sunakawa - Fumiaki Ito - Miyakoshi Tetsuo - Hiroo Matsuoka
See other presentations in this session: