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.

Decline in the severity or the incidence of schizophrenia in Japan: A survey of university students.

Clinical manifestations of schizophrenia are believed to be becoming less severe in Japan, but little evidence supports this theory. We investigated the percentages of undergraduate students attending national universities in Japan who required temporary leave and who dropped out because of schizophrenia in the academic years 1986-1987, 1994-1995, and 2013-2014. The percentages of students who required temporary leave and those who dropped out because of schizophrenia significantly decreased over time. The severity of clinical manifestations of schizophrenia may have decreased, enabling more students with schizophrenia to continue their study, or the incidence of schizophrenia might have declined.

Reliability and diagnostic validity for schizophrenia of the Japanese version of the Bonn Scale for Assessment of Basic Symptoms (BSABS).

Schizophrenia is defined by operative diagnostic criteria in DSM-IV with some typical symptoms as hallucinations and duration of the disease. Huber focused on the subjective experience of patients and coined the term "basic symptoms" and created BSABS. Our study investigated the reliability and the diagnostic validity of the 5 clusters of BSABS for DSM-IV-based diagnosis of schizophrenia with a cohort of 105 patients. Good inter-rater reliability was obtained except for one item D.10. As evaluated by Spearman's rank correlation coefficients, among the 5 clusters excluding Cluster 2, internal consistency was good. This suggests that, although each cluster is heterogeneous, cluster symptoms are the expression of physiological and biological disturbances of schizophrenia. Receiver Operating Characteristic Curve analysis was also used to show the ability of each cluster to discriminate schizophrenia. Results showed that the area representing the powers in discriminate schizophrenia of Cluster 4 "Adynamia", which is considered related to the dynamic aspect of thinking, was highest, at 0.739. Cluster 1 "Information processing disturbances" which has a predictive ability for schizophrenia showed 0.714 and Cluster 3 "Impaired tolerance to normal stress" showed 0.711. Our findings suggest that, although these clusters symptoms differ from DSM-IV criteria, they are related to fundamental process of schizophrenia. Use of some of these three clusters with other neurophysiological markers could allow clinical evaluation of schizophrenia from a new perspective.

Filicide and fatal abuse in Japan, 1994-2005: temporal trends and regional distribution.

To describe the recent filicide features in Japan, data were collected from newspaper databases between 1994 and 2005 and compared with several official statistics. From this dataset, 933 cases and 1084 victims under age 15 were identified. Fatal abuse cases were most prevalent (309 cases, or 33.1%), followed by filicide-suicide cases (303, or 32.5%) and unwanted child cases (225, or 24.1%). Infants under the age of one were most at risk (filicide rate: 2.72 per 100,000 for the same aged infants). Annual filicide numbers showed an upward trend between 1994 and 2001 and the average filicide rate per year was 0.42 per 100,000 for children under age 15. Both the number of cases over the period and the filicide rate per year by prefecture ranged widely. Furthermore, the annual filicide rates over the period were strongly correlated with both suicide rates and unemployment rates for the general population (r=.884 and .926, respectively; p<.001 for both). The measure of filicide per region and the predominating category in a prefecture provides direction for filicide prevention. Result suggests that recent socioeconomic situations have a significant effect on not only filicide-suicide but also the overall filicide rate in Japan.