The distinction between passive and active suicidal ideation (SI) and their underlying etiologies remains poorly understood. The Interpersonal Theory of Suicide implicates guilt, loneliness, and hopelessness in these SI subtypes, but there is minimal work testing these relationships in real time, capturing clinically meaningful fluctuations in SI. We conducted the first ecological momentary assessment (EMA) study to distinguish between passive and active SI in adolescents, and the first study to evaluate moment-to-moment etiological factors and mediators of passive and active SI in this age group.

Participants (N = 104) were adolescent psychiatric inpatients (Mage = 15.1; 72.12% female). They completed an EMA protocol including measures of guilt, loneliness, hopelessness, and passive and active SI for four weeks post-discharge. Multilevel modeling was used to evaluate guilt and loneliness, respectively, as predictors of prospective passive and active SI, respectively. We also evaluated whether hopelessness mediated the interaction between guilt and loneliness in predicting future SI. Hopelessness was also evaluated as a mediator between passive and active SI.

Guilt predicted prospective passive and active SI, respectively, whereas loneliness only predicted prospective passive SI. The interaction between guilt and loneliness did not predict active SI, and hopelessness did not mediate the association between guilt and active SI. Passive SI prospectively predicted active SI, but hopelessness did not mediate this association.

Findings suggest that passive and active SI may share overlap but also differences in their etiologies. Their relationship with etiological factors and mediators may differ as a function of temporal scale.