Multimodality Adaptive Intervention for Post-Inpatient Hospitalization Suicide Risk Reduction

Over 49,000 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. Just-in-time adaptive interventions (JITAIs) can help promote timely coping strategy use during periods of elevated suicidal thinking. Some people, however, will require additional interventions that explicitly target common barriers to coping effectively with suicidal thoughts. Evidence-based single-session interventions (SSIs) that address coping with suicidal thoughts exist and can be delivered in either clinician-delivered or self-guided formats. This study will use a hybrid experimental design that leverages both Sequential Multiple Assignment Randomized Trial and Micro-Randomized Trial (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. The investigators will determine the effectiveness of the JITAI for reducing the risk of suicide-related events (SREs) over three months and whether the JITAI engages target mechanisms related to coping. 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 SSIs targeting individualized barriers to coping strategy use. Response status will be assessed weekly for four weeks post-hospitalization. The investigators will determine the effectiveness of clinician-delivered vs. self-guided SSIs for reducing the risk of SREs 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 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 and SSI types. This study will result in a scalable and optimized stepped approach to reducing suicide risk during a key care transition period.