Ambulatory Assessment of Glucose Regulation in Suicidal Thoughts and Behaviors - PROJECT SUMMARY Suicide rates in the United States alarmingly increased by 37% in the last two decades. Despite extensive research efforts to identify risk factors, accurate prediction of suicidal thoughts and behaviors (STBs) remains poor. There is a critical need to improve detection of who is at greatest risk for suicide and when suicidal crises will occur to enable personalized and timely interventions. Passive ambulatory measurement methods that can detect risk for STBs in daily life, without relying on participant self-reporting during periods of distress, may be the key to making progress on this critical issue. One promising STB risk factor that is amenable to passive monitoring is peripheral glucose (blood sugar) regulation. Psychiatric and metabolic disorders are highly comorbid, and robust literature identifies abnormal glucose regulation in individuals with STBs. However, prior studies of glucose regulation in STBs were cross-sectional and retrospective, preventing the assessment of whether glucose patterns signal risk for STBs in real-time and during high-risk periods. This K23 proposes to conduct the first study examining how ambulatory glucose regulation relates to STBs in daily life. We propose to enroll 110 non-diabetic adult psychiatric inpatients with recent STBs, a population and time-period with extraordinarily high suicide risk. Participants will complete a multimodal ambulatory assessment protocol for 28 days following hospitalization, including continuous glucose monitoring and ecological momentary assessment (EMA). Using state-of-the-science analytic methods for multimodal intensive longitudinal data, we will examine passively collected glucose metrics as prospective predictors of (1) proximal suicidal ideation (captured via EMA) and suicidal behavior at follow-up (Aim 1), and (2) proximal affective-cognitive risk factors for STBs (captured via EMA) and overall affective-cognitive risk factors measured at follow-up (Aim 2). We will also explore potential mechanisms linking glucose regulation to STBs by investigating if these pathways vary across modifiable health behaviors that impact glucose regulation (Exploratory Aim 3). This knowledge could improve personalized STB risk detection and inform the development of precision interventions that target modifiable metabolic risk factors for suicide. The candidate’s training plan directly aligns with the proposed study and will provide immersive training in (1) designing and directing multimodal ambulatory assessment protocols; (2) ethical and regulatory aspects of suicide research in high-risk samples; (3) understanding and assessing metabolic risk factors for suicide; (4) advanced analyses for multimodal data; and (5) grant-writing, laboratory management, and interdisciplinary collaboration. The candidate’s team of interdisciplinary mentors, Drs. Abrantes, Schatten, Richardson, Tyrka, and Brick, are renowned experts in these topics, and Butler Hospital and Brown University provide an exceptional training environment with an extensive history of supporting career development awards. This K23 will facilitate the candidate’s successful transition to an independent research career focused on advancing suicide prediction and prevention using ecologically valid and biobehavioral approaches.