Gender differences in suicide attempters: a retrospective study of precipitating factors for suicide attempts at a critical emergency unit in Japan

Background: There is a shortage of empirical data concerning precipitating factors for suicides in Japan. The purpose of the present study was to clarify gender differences of precipitating factors for suicide attempts in Japan. Methods: The subjects were high-lethality suicide attempters who were admitted to the Nippon Medical School Hospital Critical Care Medical Center between March 1, 2010 and March 31, 2012. Precipitating factors for suicide attempt, method of suicide attempt, psychiatric diagnoses and other sociodemographic data were collected from the patients' medical records retrospectively, and statistical analyses were performed for categorical variables of male/female. Results: The total number of subjects was 193 (88 males and 105 females). The rate of subjects attempting suicide by poisonous gas was significantly higher in males while that of subjects attempting suicide by drug overdose was significantly higher in females. The rate of subjects diagnosed with major depressive disorder, bipolar disorder was significantly higher in males while that of subjects diagnosed with personality disorders or dysthymic disorder was significantly higher in females. Subjects with health problems, financial problems, work problems, debts (others) or unwanted transfer were significantly more numerous among males; subjects with family problems, parent-child relations or loneliness were significantly more frequently found among females. Conclusions: Mental disorders were the most common precipitating factor for suicide attempts regardless of gender. Significant gender differences were observed in psychiatric diagnoses, methods of suicide attempt and psychosocial problems. This indicates the necessity of suicide prevention measures corresponding to these gender differences.