Gray and white matter differences in adolescents and young adults with prior suicide attempts across bipolar and major depressive disorders

•Mood disorders, bipolar and major depressive, are major suicide risk factors.•Adolescent/young adult attempters with mood disorders have common brain circuitry.•Brain alterations common to attempters are potential targets to prevent suicide.•The brain circuitry associated with suicide attempts subserves emotion regulation.•Both gray and white matter brain alterations were associated with suicide attempts. Findings regarding brain circuitry abnormalities in suicide attempters (SAs) converge across bipolar disorder (BD) and major depressive disorder (MDD), the most common disorders observed in suicides. These abnormalities appear to be present during adolescence/young adulthood when suicide rates increase steeply, and suicide is a leading cause of death in this age group. Identification of brain circuitry common to adolescent/young adult SAs with BD and MDD is important for generating widely effective early prevention strategies. We examined brain circuitry in SAs in adolescents/young adults across these two disorders. Eighty-three participants (ages 14–25 years), 46 with BD (21 SAs) and 37 with MDD (19 SAs), underwent structural and diffusion-weighted magnetic resonance scanning. Whole-brain analyses compared gray matter (GM) volume and white matter (WM) fractional anisotropy (FA) between SAs and non-suicide attempters (NSAs) across and within BD and MDD (p