Randomized Clinical Trial of Re-Evaluating Suicidal Thoughts in Veterans

Approximately 100,000 United States Veterans have died by suicide since 2000, at age- and sex-adjusted rates which far outpace that of non-Veterans. Suicide prevention remains VA's highest priority while the investigators seek innovative, research driven approaches. Psychotherapeutic interventions for suicide prevention are one area for further innovation. Specifically, strategies from evidence-based interventions that directly address suicidality could be distilled into briefer, more scalable formats to expand access to suicide prevention interventions.

Most psychotherapies target syndromes that contribute to suicidality (e.g., depression), which is arguably inefficient for reducing suicidality. Instead, effective suicide prevention interventions should directly target mechanisms that contribute to the progression from suicidal thoughts to plans, preparations and attempts. One mechanism associated with change in suicidality is psychological inflexibility. In the context of suicide, psychological inflexibility reflects a tendency to view suicidal thoughts as distressing and problematic, resulting in struggles to eliminate them. Suicide prevention interventions may therefore be more effective if they provision adaptive skills for coping with the psychological burden of suicidal ideation (SI). Of the few existing interventions that take this approach, most are not accessible enough to adequately address the issue due to numerous barriers to mental health care. Structured web-based interventions that provision adaptive coping responses for SI present one opportunity to overcome these barriers and reduce suicidality.

Recognizing these limitations, the PI developed a brief suicide-specific intervention, Re-Evaluating Suicidal Thoughts (REST), which is designed to provision skills to improve psychological inflexibility in the context of SI. Preliminary data from two samples, both of which completed a single session of REST in the clinic, are promising.

The current proposal aims to build on that work by evaluating REST as an adjunctive suicide prevention intervention compared to treatment-as-usual (TAU) in a sample of Veterans. In this two-arm RCT, Veterans (N = 180) will be randomized (1:1) to complete REST + TAU or to maintain TAU-only. Psychological inflexibility will be indexed via self-report across five time-points (Day 1 Pre-Intervention, Day 1 Post-Intervention, Day 3, Week 1, and Week 2). Psychological inflexibility will be indexed via the Acceptance and Action Questionnaire for Suicidal Ideation (AAQ-SI). Clinical outcomes of suicidal ideation severity (self-report measurement) and self-directed violence behaviors (clinical interview) will also be measured at five time-points (Day 1 Pre-Intervention, Day 3, Week 1, Week 2, and Month 1). Suicidal ideation severity will be indexed via the Beck Scale for Suicide Ideation (BSS). Suicidal self-directed violence behaviors will be indexed via the Columbia Suicide Severity Rating Scale (C-SSRS) interview.

Aim 1. Evaluate the effect of REST on the putative therapeutic mechanism, psychological inflexibility. Hypothesis 1. Compared to TAU, REST will be associated with significant differences between conditions in psychological inflexibility at Week 2, controlling for baseline psychological inflexibility.

Aim 2. Evaluate the effect of REST on (a) suicidal ideation severity and (b) self-directed violence. Hypothesis 2a and b. Compared to TAU, REST will be associated with significant differences between conditions in (2a) suicidal ideation severity and (2b) self-directed violence at Month 1, controlling for baseline suicidal ideation or behaviors.

Aim 3. Evaluate the mechanism through which REST reduces suicidal ideation severity and behaviors. Hypothesis 3a and b. Differences in psychological inflexibility at Week 2 will mediate differences in (3a) suicidal ideation severity and (3b) suicidal behaviors at Month 1, controlling for baseline variables.

Recruitment. Veterans will be recruited from the Southeast Louisiana Veterans Health Care System (SLVHCS).

Personnel. The study coordinator will conduct the initial contacts regarding study interest, schedule participants, administer study measures, and conduct chart review. The PI will conduct preliminary eligibility screenings based on chart review.

Day 1/Intervention Appointment. Upon presentation to SLVHCS for the Day 1 appointment Veterans will complete informed consent. Next they will complete a battery of baseline self-report measures, followed by the C-SSRS interview and safety planning intervention with a clinician. Eligible Veterans will then be randomized to condition. Randomization will occur at the individual level. Participants will be randomized at a 1:1 ratio to one of two conditions, REST + TAU or TAU-only control. Veterans assigned to the REST + TAU condition will complete the REST intervention alone on a computer or mobile device. Following the intervention they will complete a post-intervention self-report measure of psychological inflexibility. Veterans who are assigned to the TAU-only control condition will complete a post-assessment self-report measure of psychological inflexibility.

Follow-up Appointments. There will be four follow-up appointments that follow the Day 1/Intervention appointment. These will occur at Day 3, Week 1, Week 2, and Month 1. Appointment procedures will be nearly identical between conditions and across appointments, with one exception for the Month 1 appointment during which time Veterans assigned to TAU-only will be offered the opportunity to complete the REST intervention. Veterans will be given the choice of completing the follow-up appointments over virtual telehealth modalities or face-to-face.