Importance: Early-onset bipolar disorder conveys substantial risk for suicide. No psychosocial intervention for this population expressly targets suicidal behavior.
Objective: To determine whether dialectical behavior therapy (DBT) for adolescents with bipolar spectrum disorder is more effective than standard of care (SOC) psychotherapy in decreasing suicide attempts over 1 year.
Design, settings, and participants: Adolescents aged 12 to 18 years diagnosed with bipolar spectrum disorder were recruited from a specialty outpatient psychiatric clinic between November 2014 and September 2019. Independent evaluators conducted quarterly assessments over 1 year with participants and parents. Data were analyzed from March 2021 to November 2022.
Interventions: Participants were randomly assigned to 1 year of DBT (36 sessions; n = 47) or SOC psychotherapy (schedule clinically determined; n = 53). All youth received medication management via a flexible algorithm.
Main outcomes and measures: Primary outcomes included suicide attempts over 1 year and mood symptoms and states (depression and hypomania/mania). Secondary analyses included moderation of DBT effects by history of suicide attempt and mediation through emotion dysregulation.
Results: Of 100 included participants, 85 (85%) were female, and the mean (SD) age was 16.1 (1.6) years. Participants were followed up over a mean (SD) of 47 (14) weeks. Both treatment groups demonstrated significant and similar improvement in mood symptoms and episodes over 1 year (standardized depression rating scale slope, -0.17; 95% CI, -0.31 to -0.03; standardized mania rating scale slope, -0.24; 95% CI, -0.34 to -0.14). DBT and SOC participants reported similar suicide attempt rates at intake as measured on the Adolescent Longitudinal Follow-Up Evaluation (ALIFE; mean [SD] attempts, 2.0 [4.5] vs 1.8 [3.9], respectively; P = .80). DBT participants reported slightly more suicide attempts at intake as measured on the Columbia-Suicide Severity Rating Scale Pediatric Version (C-SSRS; mean [SD] attempts, 1.4 [3.6] vs 0.6 [0.9]; P = .02). DBT participants reported significantly fewer suicide attempts over follow-up compared with SOC participants via the ALIFE (mean [SD] attempts per follow-up period, 0.2 [0.4] vs 1.1 [4.3], controlling for baseline attempts: P = .03) and the C-SSRS (mean [SD] attempts per follow-up period, 0.04 [0.2] vs 0.10 [0.3], controlling for baseline attempts; P = .03). DBT was significantly more effective than SOC psychotherapy at decreasing suicide attempts over 1 year (ALIFE: incidence rate ratio [IRR], 0.32; 95% CI, 0.11-0.96; C-SSRS: IRR, 0.13; 95% CI, 0.02-0.78). Decreased rate of suicide attempts in DBT was moderated by presence of lifetime history of suicide attempt and time (IRR, 0.23; 95% CI, 0.13-0.44) and mediated by improvement in emotion dysregulation (IRR, 0.61; 95% CI, 0.42-0.89), particularly for those with high baseline emotion dysregulation (standardized β, -0.59; 95% CI, -0.92 to -0.26).
Conclusions and relevance: In this randomized clinical trial, DBT demonstrated efficacy in decreasing suicide attempts among the high-risk population of adolescents with bipolar spectrum disorder.
Trial registration: ClinicalTrials.gov Identifier: NCT02003690.