Comparative Network Structures of Hikikomori (Social Withdrawal) Symptoms in Korean and Japanese Psychiatric Patients Prescribed Antidepressants: Findings From the Research on Asian Psychotropic Patterns for Antidepressants, Phase 3

Abstract

Background: This study aimed to compare the symptom structures of hikikomori in Korea and Japan through a network analysis approach, addressing the scarcity of comparative research and elucidating potential cross-cultural differences in its manifestation. Methods: Data were derived from the Research on Asian Psychotropic Prescription Patterns, Phase 3 (REAP-AD3) study, involving psychiatric patients in Korea and Japan. Social withdrawal symptoms were assessed using the one-month version of the 25-item Hikikomori Questionnaire (HQ-25M). Network analyses were performed to characterize symptom interconnections and centrality in both cohorts. Differences in network structure, edge strength, and global strength were evaluated using the network comparison test (NCT). Results: The NCT indicated no statistically significant differences in network structure invariance between Korean and Japanese patients. Notably, the most frequently endorsed symptom among Korean psychiatric patients was “no one to discuss important matters with,” whereas for Japanese psychiatric patients it was “difficulty enjoying social situations.” Conclusion: Although overall network structures were largely comparable, the findings suggest subtle distinctions in the organization of social withdrawal symptoms between Korean and Japanese psychiatric patients. These differences underscore the importance of developing culturally tailored preventive and therapeutic strategies for hikikomori in these populations.