Suicidal disclosures among friends: using social network data to understand suicide contagion.

A robust literature suggests that suicide is socially contagious; however, we know little about how and why suicide spreads. Using network data from the National Longitudinal Study of Adolescent to Adult Health, we examine the effects of alter's (1) disclosed and (2) undisclosed suicide attempts, (3) suicide ideation, and (4) emotional distress on ego's mental health one year later to gain insights into the emotional and cultural mechanisms that underlie suicide contagion. We find that when egos know about alter's suicide attempt, they report significantly higher levels of emotional distress and are more likely to report suicidality, net of extensive controls; however, alter's undisclosed suicide attempts and ideation have no significant effect on ego's mental health. Finally, we find evidence that emotional distress is contagious in adolescence, though it does not seem to promote suicidality. We discuss the implications of our findings for suicide contagion specifically and sociology more generally. © American Sociological Association 2015.