Older Veterans are an important and understudied population for suicide prevention. Adults 65 years and older will be 20% of the US population and 50% of the Veteran population by 2030. It has been documented that the majority of decedents who die by suicide in the Veteran population are Veterans 50 years and older (≥ 69%) and over 40% Veterans 65 years and older. Moreover, older adults, including Veterans, have high rates of premeditated lethal means of suicide method indicating less impulsivity and more opportunity to intervene; thus, studying older Veterans is a high priority for supporting suicide prevention. In the current proposal, our objective is to understand the combination of factors that lead to suicide death for aging Veterans by identifying the short- and long-term typologies that best characterize suicide death among older Veterans and by examining pathways from suicide attempt to mortality. Thus far, our research suggests that there are distinct acute medical and psychiatric profiles and potential trajectories that may influence an older individual’s long- term risk of suicide and employment of lethal means, which further influences policies and strategies for mitigation and prevention. To capture these profiles and trajectories, we will use latent clustering techniques to uniquely characterize (separately by social and clinical characteristics) those who attempt and die by suicide. The current proposed research builds on a productive, ongoing body of suicide research in older Veterans. Our work has informed prognostic factors (e.g., psychoactive medication use), timing and burden of diagnosis (i.e., recent diagnosis of mild cognitive impairment or dementia), and life transitions (i.e., reentry into community from incarceration) associated with increased risk of suicide attempt. Yet, major gaps remain in our understanding of how best to characterize risk for lethality of suicide attempt. Short- and long-term precursors delineated by profiles and trajectories of social risk factors (e.g., housing instability, financial strain, interpersonal violence) may inform suicide risk and lethal means of suicide death (e.g., firearms, drug overdose). We propose in this current application to build on the nationally representative cohort for late-life suicide research formed in the PI’s existing CSR&D Merit Award project (the “Older Veteran Suicide Risk Dataset”, CX001119; PI: Byers) with new questions to determine profiles, trajectories, care transitions, and social and clinical factors contributing to risk of suicide attempt and death by suicide in aging Veterans. This unique cohort comprises all Veterans (~5,000,000) who used VA health care services and were aged 50 years and older in fiscal year 2012-2013, prospectively followed to present with data updated annually. The cohort includes information on demographics, all psychiatric and medical diagnoses, prescription medication use, laboratory measures, and information on all suicide-relate...