The longitudinal relationship between co-rumination and depressive symptoms in adolescents: A systematic review and...

Co-rumination is associated with depressive symptoms in adolescents, yet the temporal directionality remains unclear because previous meta-analyses have relied largely on cross-sectional evidence. This study examined the longitudinal associations between co-rumination and depressive symptoms and tested moderators using meta-analytic structural equation modeling.

Following a preregistered protocol, seven databases were systematically searched for longitudinal studies. Forty-six datasets comprising 18,222 participants were included. One-stage meta-analytic structural equation modeling was used to estimate cross-lagged panel models from pooled correlation matrices. Moderators included age, gender, publication year, individualism, time lag, study quality, co-rumination partner, co-rumination modality, and measurement instruments. Sensitivity analyses examined T1-Tlast associations and modeled co-brooding and co-reflection separately.

T1 co-rumination prospectively predicted T2 depressive symptoms (β = 0.036, p = .020), and T1 depressive symptoms showed a small association with T2 co-rumination (β = 0.031, p = .0495). The forward pathway was consistent across sensitivity analyses, with co-brooding showing the most robust forward association; the reverse pathway was attenuated under T1-Tlast extraction. After Benjamini-Hochberg correction, only measurement instruments significantly moderated the cross-lagged paths; publication year showed a suggestive but non-significant omnibus effect. Gender, age, time lag, study quality, individualism, co-rumination partner, and co-rumination modality were not significant moderators.

Co-rumination is a small but reliable prospective predictor of adolescent depressive symptoms, with co-brooding showing the most consistent forward prediction. The weaker, less robust reverse pathway argues against a strong reciprocal cycle. Future research should examine whether targeting maladaptive, repetitive co-brooding in close peer relationships may benefit prevention efforts.