It’s quite effective for treating depression, especially when depression is chronic, treatment-resistant, or combined with other issues like emotional dysregulation or suicidal ideation.

1. General effectiveness

Several studies show DBT extensively improves depressive symptoms:

• • Harley et al. (2008) discovered that adults with treatment-resistant depression who completed DBT reported substantial decreases in depression scores compared to those who didn’t.
  • In a meta-analysis by Kliem et al. (2010), DBT was associated with moderate to large reductions in depressive symptoms across multiple clinical groups, not just those with borderline personality disorder.

2. For treatment-resistant depression

DBT has been useful where other treatments failed.

• • Lynch et al. (2007) studied older adults with chronic depression and found that a modified version of DBT (DBT for depression) led to greater improvement compared to treatment-as-usual, including in hopelessness and self-harm risk.

This is important because around one-third of people with major depression don’t fully respond to traditional treatments like medication or standard CBT alone.

3. Impact on suicidality
   
   

DBT’s focus on suicidality makes it greatly relevant, since many people with depression experience suicidal thoughts.

It’s one of the few therapies proven to directly reduce suicide attempts.

4. Why it’s useful for depression

• • It directly addresses emotional suffering rather than just cognitive distortions.
  • It educates coping skills that people can apply immediately in daily life.
  • It combines acceptance strategies (like radical acceptance) with change strategies (like behavioral activation), which seems to work better for complex cases than pure “fix it” approaches.

Some additional numbers:

• • Depression scores often drop by about 30%–50% following a full DBT program, depending on the severity and specific group studied.

DBT isn’t the first-line treatment for mild to moderate depression (like CBT is usually recommended first).

But DBT can be a game-changer for those with chronic, severe, emotionally intense, or treatment-resistant depression.