Risk Factors of Poor Mental Health Outcomes When Studying Abroad: A Retrospective Cohort Study at a Japanese University

Background: In higher education, globalization has been rapidly developing worldwide. In general, adolescent and young-adulthood are highly risky for mental health. Especially, international students have poorer supporting resources and higher hurdles to get any information in help-seeking behavior than local students. They are apart from their family and exposed to new cultures, and some develop severe mental health disorders, resulting in poor outcomes such as suicide. However, there are no cohort studies on these poor outcomes. Thus, we elucidated how to prevent poor mental health outcomes when studying abroad via a five-year retrospective cohort study undertaken at a Japanese university. Results: Demographic data, language ability, diagnoses, main stressors, and help-seeking behavior were analyzed and then poor and non-poor outcome cases were compared. In the poor outcome cases, the ratio of delusional psychosis was higher than that in the non-poor outcome cases. The other cases in the poor outcome cases were categorized as common mental disorders, such as depressive withdrawal disorders. Long distance regions from the host country and the non-regular student status showed higher risks for poor mental health outcomes, but their Japanese ability did not show any meager tendency, comparing with non-poor outcome cases. The group of delusional psychoses had an earlier onset, and culture shock was experienced. In contrast, the group of depressive withdrawal disorders had a later onset and were related to individual vulnerabilities. Conclusion: For the prevention of poor outcome cases, general social support and health education, such as anti-stigma for mental health, is essential. Especially, for the prevention of delusional psychosis, mother tongue use and home culture connection should be promoted for newcomers to gradually acclimatize in host countries. For depressive withdrawal disorders, a comprehensive approach of early detection, intervention, and health advice for both students and supervisors is necessary.