Multimodality Adaptive Intervention for Post-Inpatient Hospitalization Suicide Risk Reduction - ABSTRACT Over 48,000 Americans die by suicide each year, making suicide the 11th leading cause of death across all ages. The highest-risk time for suicidal behavior is the three months after inpatient psychiatric hospitalization, during which engagement with traditional outpatient care is low. Recent real-time monitoring research has revealed that suicidal thoughts fluctuate rapidly, over hours or even minutes, highlighting the need for dynamic interventions that adapt to time-varying changes in risk. We recently developed a just-in-time adaptive intervention (JITAI) that promotes coping strategy use during periods of elevated suicidal thinking. Our recent micro-randomized trial (MRT; N=71 adults hospitalized for suicide risk), showed the feasibility, acceptability, and preliminary effectiveness of this JITAI for promoting in-the-moment coping strategy use during the four weeks after inpatient discharge. Some patients, however, require additional interventions that explicitly target common psychological and practical barriers to coping effectively with suicidal thoughts. Evidence-based single-session interventions that address coping with suicidal thoughts exist and can be delivered in either clinician-delivered or self-guided formats. In this study, we will use a hybrid experimental design that leverages both Sequential Multiple Assignment Randomized Trial and MRT methods to build and evaluate a multimodality adaptive intervention comprising stepped evidence-based intervention components sequenced and adapted at multiple timescales following inpatient hospitalization. Aim 1 will compare two first-stage interventions: JITAI vs. self-monitoring alone for four weeks after inpatient discharge. We will determine the effectiveness of the JITAI for reducing the risk of distal outcomes (suicide attempts or emergency visits/re-hospitalizations for suicide risk) over three months and whether the JITAI engages target mechanisms related to coping strategy use. Aim 2 will compare two second- stage interventions for those who do not sufficiently respond to the first-stage interventions: clinician-delivered or self-guided single-session interventions targeting individualized barriers to coping strategy use. Response status will be assessed weekly for four weeks post-hospitalization. We will determine the effectiveness of clinician-delivered vs. self-guided single-session interventions (delivered up to three times per participant) for reducing the risk of distal outcomes among insufficient responders, as well as effect differences between embedded adaptive interventions among all participants. Aim 3 will determine the within-person effects of just- in-time messages (sent or not sent in response to each self-monitoring report of elevated suicide urge or intent) on proximal outcomes (next-hour coping strategy use and momentary suicidal thoughts) for participants in the JITAI condition. Just-in-time message effects will be evaluated when averaging across second-stage conditions and contrasting message types (personalized coping strategies drawn from each individual’s safety plan vs. general recommendations) and single-session interventions (clinician-delivered vs. self-guided). This study will result in a scalable and optimized stepped approach to reducing suicide risk during a key care transition period.
