Detecting and distinguishing indicators of risk for suicide using clinical records.

Health systems are essential for suicide risk detection. Most efforts target people with mental health (MH) diagnoses, but this only represents half of the people who die by suicide. This study seeks to discover and validate health indicators of suicide death among those with, and without, MH diagnoses. This case-control study used statistical modeling with health record data on diagnoses, procedures, and encounters. The study included 3,195 individuals who died by suicide from 2000 to 2015 and 249,092 randomly selected matched controls, who were age 18+ and affiliated with nine Mental Health Research Network affiliated health systems. Of the 202 indicators studied, 170 (84%) were associated with suicide in the discovery cohort, with 148 (86%) of those in the validation cohort. Malignant cancer diagnoses were risk factors for suicide in those without MH diagnoses, and multiple individual psychiatric-related indicators were unique to the MH subgroup. Protective effects across MH-stratified models included diagnoses of benign neoplasms, respiratory infections, and utilization of reproductive services. MH-stratified latent class models validated five subgroups with distinct patterns of indicators in both those with and without MH. The highest risk groups were characterized via high utilization with multiple healthcare concerns in both groups. The lowest risk groups were characterized as predominantly young, female, and high utilizers of preventive services. Healthcare data include many indicators of suicide risk for those with and without MH diagnoses, which may be used to support the identification and understanding of risk as well as targeting of prevention in health systems.

Endoplasmic reticulum aminopeptidase-1 functions regulate key aspects of the innate immune response.

Endoplasmic reticulum aminopeptidase-1 (ERAP1) is a multifunctional, ubiquitously expressed enzyme whose peptide-trimming role during antigen processing for presentation by MHC I molecules is well established, however, a role for ERAP1 in modulating global innate immune responses has not been described to date. Here we demonstrate that, relative to wild type mice, mice lacking ERAP1 exhibit exaggerated innate immune responses early during pathogen recognition, as characterized by increased activation of splenic and hepatic NK and NKT cells and enhanced production of pro-inflammatory cytokines such as IL12 and MCP1. Our data also revealed that ERAP1 is playing a critical role in NK cell development and function. We observed higher frequencies of terminally matured NK cells, as well as higher frequencies of licensed NK cells (expressing the Ly49C and Ly49I receptors) in ERAP1-KO mice, results that positively correlated with an enhanced NK activation and IFNγ production by ERAP1-KO mice challenged with pro-inflammatory stimuli. Furthermore, during pathogen recognition, ERAP1 regulates IL12 production by CD11c(+) DCs specifically, with increases in IL12 production positively correlated with an increased phagocytic activity of splenic DCs and macrophages. Collectively, our results demonstrate a previously unrecognized, more central role for the ERAP1 protein in modulating several aspects of both the development of the innate immune system, and its responses during the initial stages of pathogen recognition. Such a role may explain why ERAP1 has been implicated by GWAS in the pathogenesis of autoimmune diseases that may be precipitated by aberrant responses to pathogen encounters.