1 Department of Psychology, Concordia University, Montreal, Quebec, Canada.
2 Department of Psychiatry, McGill University, Montreal, Quebec, Canada.
3 McGill Group for Suicide Studies, Douglas Mental Health University Institute, Montreal, Quebec, Canada.

Introduction: Adolescents at risk for suicidal ideation tend to report more unmet interpersonal needs, namely perceived burdensomeness and thwarted belongingness. Interpersonal capitalization-an interpersonal process involving disclosing a positive personal event to others and evaluating others' responsiveness to such disclosure-can promote positive affect and social connectedness. This study examined whether daily capitalization attempts and perceived active-constructive responses to the capitalization attempts were associated with fluctuations in positive affect and unmet interpersonal needs among adolescents at varying risk of suicidal ideation.

Methods: Adolescents (M_age = 15.55; range = 12-18) with and without major depression, at respectively higher risk (n = 23) and lower risk (n = 32) for suicidal ideation, completed 10 consecutive daily diaries reporting on interpersonal capitalization, positive affect, perceived burdensomeness, and loneliness (as a proxy for thwarted belongingness).

Results: Within-person hierarchical linear modeling analyses showed that daily capitalization attempts and perceived active-constructive responses were associated with higher same-day positive affect in both groups. In the higher-risk group, daily capitalization attempts were associated with lower same-day perceived burdensomeness (b = -0.102, p < 0.05) and perceived active-constructive responses were related to lower daily loneliness (b = -0.279, p < 0.001).

Conclusion: Daily interpersonal capitalization processes may represent a protective interpersonal pathway linked to reduced suicidal ideation over time, particularly among higher-risk adolescents.