Several suicide attempts presented at the emergency department are due to drug overdose associated with psychiatric disorders. We examined and identified the major risk factors among Japanese drug overdose patients and several close associations of suicide risk. We enrolled 101 patients who attempted suicide by drug overdose between January 2015 and April 2018, assessed their background using the SAD PERSONS scale, and performed association rule analysis to characterize the major risk factors and their associations. We identified three main nodes-depressive state, social support lacking, and no spouse-as considerable risk factors. Furthermore, we identified several close associations of suicide risk and their intensity; in cases with previous suicide attempts and ethanol abuse or substance use, a simultaneous social support lacking is likely. These findings align with previous studies that used conventional statistical analysis on suicide and suicide attempt risk and highlight its importance.
Keywords: SAD PERSONS scale; depressive state; drug overdose; social support lacking; suicide attempts.