Yotaro Katsumata

Mental disorders and suicide in Japan: a nation-wide psychological autopsy case-control study.

BACKGROUND The purpose of the present nationwide psychological autopsy case-control study is to identify the association between mental disorders and suicide in Japan, adjusting for physical conditions. METHODS A semi-structured interview was conducted of the closest family members of 49 suicide completers and 145 gender-, age-, and municipality-matched living controls. The interview included sections of socio-demographic characteristics, physical conditions, and a psychiatric interview producing DSM-IV diagnoses of mental disorders prior to suicide (or at survey). We compared prevalences of mental disorders between the two groups, using conditional logistic regression. RESULTS A significantly higher proportion with any mental disorder was found in the suicide group (65.3%) compared to the control group (4.8%) (p=0.003, odds ratio [OR]=7.5). The population attributable risk proportion associated with mental disorder was 0.24. Mood disorder, particularly major depressive disorder, was the most strongly associated with suicide (p<0.001). Anxiety disorder, alcohol-related disorder, and brief psychotic disorder were also significantly associated with suicide (p<0.05). These patterns were unchanged after adjusting for serious chronic physical conditions. LIMITATIONS The present study had some limitations, such as small sample size, sampling bias and information bias. CONCLUSIONS Most mental disorders, particularly mood disorder, were significantly associated with a greater risk of suicide in Japan, independent of physical conditions. Mental disorders are a major target of suicide prevention programs in Japan.

Suicide risk among individuals with sleep disturbances in Japan: a case-control psychological autopsy study.

OBJECTIVE This case-control psychological autopsy study aimed to explore a relationship between sleep disturbances and suicide among Japanese, as well as determine the importance and usability of screening for sleep disturbances in suicide prevention. METHODS A semi-structured interview was conducted with the close family members of 49 adult suicide completers and 145 gender-, age-, and residential municipality-matched living controls. The survey included sections on demographics, sleep disturbances, and mental disorders. Conditional logistic regression analyses were performed to compare sleep disturbance prevalence between the two groups. RESULTS A significantly higher prevalence of sleep disturbances was found among the suicide group (75.5%) compared to the controls (11.0%) (odds ratio [OR]=21.6, p<0.001). The association remained significant after adjusting for mental disorders (OR=12.7, p<0.001). The population attributable risk percent of suicide associated with sleep disturbances and mental disorders was estimated to be 56.4% and 35.3%, respectively. CONCLUSIONS The study confirmed that sleep disturbances are an important risk factor of suicide, independent of mental disorders. Sleep disturbances accounted for a greater proportion of suicide cases than did mental disorders in the Japanese population given the higher prevalence, and could thus be considered an important target in suicide prevention in Japan.

Psychosocial and psychiatric characteristics of suicide completers with psychiatric treatment before death: A psychological autopsy study of 76 cases

Aim:  The present study was conducted to examine differences in psychosocial and psychiatric characteristics between suicide completers with and without a history of psychiatric treatment within the year before death, using a psychological autopsy method.

Analgesia during self-cutting: Clinical implications and the association with suicidal ideation

The present study examined the association of suicidal ideation in self‐cutters with clinical features of self‐cutting, using a sample of subjects from juvenile correctional institutions. Multivariate analysis revealed that male self‐cutters and analgesia during self‐cutting were significantly associated with a history of suicidal ideation. These results suggest that male analgesic self‐cutters should be regarded as a high‐risk subgroup for suicide.

Suicide prevention strategies in Japan: A 15-year review (1998-2013)

Suicide is a global public health problem and solutions to it can be found only through a global dialog. The suicide rate in Japan has been alarming, but Japan has made substantial efforts to reduce this rate, making prevention a high priority. This report reviews the developmental stages of a comprehensive policy of suicide prevention in Japan from 1998 to 2013. Our review suggests that suicide prevention activities were facilitated by the 2006 Basic Act for Suicide Prevention and the 2007 General Principles of Suicide Prevention Policy. Along with the establishment of a Special Fund program for local governments, the Basic Act and General Principles led to the development of a comprehensive and multi-sector approach to suicide prevention. Suicide rates in Japan, especially among middle-aged men, decreased consistently after 2009, suggesting that the initiatives were effective. Continuous monitoring is needed to evaluate Japan’s suicide prevention policy.

Psychosocial and psychiatric aspects of suicide completers with unmanageable debt: A psychological autopsy study

This study examined the psychosocial and psychiatric features of 16 Japanese suicide completers with unmanageable debt compared with 23 suicide completers without such debt at time of death, using a psychological autopsy method. The individuals with unmanageable debt were more likely to have been self‐employed and to have experienced divorce. They were less likely to have engaged in help‐seeking behavior, despite having mental health problems. Our findings suggest that providing comprehensive support and promoting help‐seeking behavior may be important for suicide prevention in middle‐aged men.

Exploring suicide risk factors among Japanese individuals: The largest case-control psychological autopsy study in Japan

This case-control psychological autopsy study explored suicide risk factors among Japanese individuals. We targeted 102 suicide completers over 20 years of age and 334 living controls matched to suicide cases by gender, age, and residential municipality in Japan. After controlling for other factors, we found significant associations between suicide and mental disorders, sleeping problems, and verbal communication of ones own death. We discuss the importance of sensitive responses to verbal expressions of suicidal ideation.