Suicide among national university graduate students in Japan from 2002 to 2021

Aim: Graduate students are exposed to various types of stress. Thus, they are prone to mental health problems, and the most devastating result is suicide. The aim of this paper is to reveal the status of suicide among graduate students in Japan for 20 years. Methods: We analyzed cumulative data on suicide among national university graduate students from annual surveys on causes of non-graduation in Japan for the 2002-2003 through 2021-2022 academic years. We asked all national universities with graduate schools to complete the surveys, and the participation rate was 91.1%. Results: The total number of students in the surveys was 2,383,858, and the number of deaths by suicide was 347 (292 males, 55 females). Chi-squared test results showed significantly higher suicide mortality rates for the following groups: male (p < 0.001), temporary leave (p < 0.001), repeating the same year (p = 0.006), master's level (p = 0.005), and majoring in engineering (p < 0.001). Psychiatric diagnoses were detected among 44 students (12.7%). The largest distribution (27 cases) of International Classification of Diseases, Tenth Revision (ICD-10) codes among those whose diagnoses were evident was F3, mood disorders. Estimated motives for suicide were reported for only 36 students (10.4%), of which the most prevalent was job search failure. The most prevalent suicide method was hanging (151 cases, 43.5%). Conclusion: Our findings indicate that student support facilities should recognize higher-risk groups for suicide among graduate students. Our study adds suggestions for suicide prevention on campus during future pandemics.