About 1.4% of U.S. adults (over 3 million people) experience Borderline Personality Disorder (BPD) in a typical year. But BPD is difficult to treat. Evidence for the effectiveness of medications alone to treat BPD symptoms is limited. A form of talk therapy called dialectical behavior therapy (DBT) originally designed to reduce suicidal behaviors has often been effective in treating people with BPD.

But BPD often co-occurs with other psychiatric illnesses including major depression, and it is associated with an exceptionally high risk of suicidality, especially among patients with comorbid depression. DBT can help many people to reduce their self-harming behaviors, but additional treatment approaches are urgently sought to address the risk of suicidal behavior associated with BPD. It has been estimated that as many as 10% of BPD patients end their lives in suicide, and that over 80% make at least one suicide attempt during their life.

Now, a team of researchers led by 2014 BBRF Young Investigator Anthony C. Ruocco, Ph.D., of the University of Toronto and Centre for Addiction and Mental Health, has reported encouraging results of a small feasibility trial of a new treatment combination for severely suicidal patients with BPD and co-occurring treatment-resistant depression. The team treated 9 such patients with DBT and “conjoint” magnetic seizure therapy (MST) for 5 weeks, and compared impacts on their symptoms—especially suicidal ideation and depression, as well as cognitive performance—with 10 similar patients who received only DBT for 5 weeks.

Conjoint therapies are those administered in concert. In this case, participants in both groups received 1 hour weekly of individual DBT and 1 hour of weekly DBT skills training focused on distress tolerance. Participants in the “conjoint therapy” group received these DBT treatments plus up to 15 MST treatments (up to 3 per week) over the 5 weeks of the trial. The participants were volunteers who were currently experiencing moderate-to-severe suicidal symptoms, and each was allowed to choose whether to be in the DBT-only or the DBT plus MST group.

MST is a form of non-invasive brain stimulation that has been associated in some trials with significant reduction of suicidal ideation in patients with treatment-resistant depression. It had not been tested previously in BPD. MST uses magnetic pulses to induce a brief seizure in the brain that is intended to have therapeutic effects. In its object, it is similar to electroconvulsive therapy (ECT), but it is designed to act more focally, i.e., in a smaller, targeted area or areas in the brain. ECT is associated with short-term memory loss in some patients, while MST in testing to date has been associated with fewer such cognitive side effects.

BPD’s symptoms vary from patient to patient, and are diverse. A diagnosis requires that the patient meet general diagnostic criteria for a personality disorder, as defined in the DSM-5 manual. This means having a disturbance in at least two of four domains: identity, interpersonal functioning, impulse control, and emotion regulation. For BPD specifically, one needs to meet any combination of five of nine potential symptoms. Impulse control symptoms involve things like substance abuse, binge eating, reckless driving, etc. These often go hand in hand with self-harming behavior, which is often related to emotion-regulation abilities and impulse control. People with BPD experience intense emotions and have a difficult time getting back to their baseline level of emotion. Some patients express fears of abandonment; some have chaotic, turbulent, up-and-down relationships with people close to them.

Although the trial led by Dr. Ruocco and colleagues was small, it did generate hopeful results. Combined DBT and MST treatments led to a “rapid, significant, and clinically meaningful reduction in suicidal ideation” at the end of the 5-week study period, the team reported in the inaugural issue of Nature Mental Health. This reduction in suicidality was sustained at a 4-month follow-up assessment.

Conjoint DBT + MST was also associated with “significant reductions in depression and BPD interpersonal symptom severity,” the team reported, “but neither effect was sustained at the 4-month follow-up. Importantly, there were no observed impacts of MST therapy on cognition, and there were no treatment-related serious adverse effects.

These initial results lead the team to suggest that the DBT + MST combined therapy is “feasible” to offer, and “warrants further exploration” in a larger placebo-controlled clinical trial (with some patients receiving a treatment that sounds and feels like MST but is not delivering actual stimulation to the brain). They also suggest that rTMS, a commonly used form of brain stimulation, might be tested in combination with DBT in suicidal patients with BPD. For now, they said, their results “represent a step toward addressing the long-standing problem of suicidality in BPD.”

The researchers note that their results do not suggest that DBT alone is ineffective, rather that the combination of DBT and MST was associated with a more rapid reduction in suicidality compared with 5 weeks of DBT alone. They also note that on the basis of their study it was not possible to determine if improvements in interpersonal BPD symptoms in the combined therapy group “were a cause or consequence of reductions in suicidal ideation.” That is a subject for future studies.

The research team also included senior member Zafiris J. Daskalakis, M.D., Ph.D., BBRF Scientific Council, 2008 BBRF Independent Investigator, 2006 and 2004 Young Investigator; co-first author Jenna M. Traynor Ph.D., 2022 BBRF Young Investigator; and Daniel M. Blumberger, M.D., 2010 BBRF Young Investigator. Dr. Ruocco’s 2014 BBRF Young Investigator grant, devoted to the work reported in the new paper, was supported by The Families for Borderline Personality Disorder Research.