Social media monitoring of suicidal content and change in trends of Japanese twitter content around the Zama suicide pact slayings.

Social media-related suicides remain a serious issue despite efforts to address this problem. On October 31st, 2017, the Zama Suicide Pact Slayings were reported in which a criminal targeted victims who expressed suicidal ideation using social media. We analyzed how communication on Twitter was used concerning suicidal ideation in relation to the slayings. We extracted data from 1,246 Twitter accounts using the hashtag "#I_want_to_die" between October 1st to November 30th, 2017. We performed thematic content analysis to identify the characteristics of these Twitter accounts and their tweets. The number and categories of related posts from before and after the slayings were compared. Relevant online communication increased from 159 to 1,037 Twitter accounts after the incident. Before the incident, most accounts had tweets related to suicide, mental health issues, or sought to make connections. After the incident, most tweets from these accounts were related to opinions (especially offensive ones) or non-prevention-oriented advertisements. The results suggest that the number of accounts tweeting suicidal-related themes decreased after the homicides, while the number of accounts posting offensive opinions and non-preventive advertisements increased. This implies that the efficacy of social media-based prevention measures may be undermined by this content.