Differences in characteristics between suicide victims who left notes or not

Background: Suicide notes (SN) are one of markers of the severity of a suicide attempt and are said to provide a valuable insight into the thinking of suicide victims before the fatal act [Shah, A., De, T., 1998. Suicide and the elderly. Int. J. Psychiat. Clin Pract. 2, 3-18]. To examine whether suicide victims who wrote notes (note writers: NW) differ from those who did not, we investigated the characteristics of a sample of more than 5000 Japanese suicides using multiple logistic regression analysis. Methods: For all suicide victims (5161 cases), we examined the following information: gender, age, suicide method, reason for suicide, marital status, residential status, history of psychiatric disorders, previous suicidal behavior, physical disease, and content of suicide notes. Results: Mean incidence of NW was 30.1% (male: 29.7%, female: 30.8%). NW in Japan had the following characteristics; higher proportion in female and living alone, suicide by more lethal methods such as carbon monoxide, hanging or sharp instruments. On the other hand, non-NW had tendencies to commit suicide for reasons of physical illness and psychiatric disorder, and/or history of previous psychiatric disorders. Limitations: This study is observational and discusses only completed, not attempted, suicide. Medical and psychiatric comorbidity are judged only by the history of diagnosis and the information about the problems in relationships is based not on valid criteria for inclusion. Conclusions: Although these findings show ethnic differences, it is possible that SN may be considered an indicator of a serious suicide attempt. Further studies of SN are needed to confirm this. (c) 2006 Elsevier B.V. All rights reserved.