PROJECT ABSTRACT Bacterial and fungal infections associated with drug use are increasing substantially in the United States. Two such infections, skin and soft tissue infections (SSTI) and infective endocarditis (IE), can lead to significant illness or death among people who use drugs (PWUD). SSTIs, such as abscesses and cellulitis, are highly prevalent with up to 65% of people who inject drugs reporting recent SSTIs. IE is an infection of the heart that typically requires long-term hospitalization. In addition to these infections, some PWUD face other pressing health concerns, most notably opioid use disorder and overdose. Infection-related mortality may be a substantial contributor to all-cause mortality among PWUD. However, from a population perspective, little is known about the determinants and burden of infection-related mortality relative to drug overdose among PWUD. Among some PWUD, opioid use disorder is a potentially serious yet treatable condition. FDA approved medications are known to reduce opioid use disorder symptoms and modify underlying behaviors that may increase risk of infections and overdose, such as injection drug use. Race, ethnicity, and gender inequities in access to and use of medication for opioid use disorder (MOUD) exist, and the role of intersectionality of these identities in MOUD access or use are not known among those receiving care for infectious diseases. The overall objective of this proposal is to expand the knowledge base concerning infection-related mortality, fatal and nonfatal drug overdose, and all-cause mortality in PWUD diagnosed with SSTIs and IE, with a particular focus on opioid use disorder. Primarily, the project will document the burden and predictors of infection and drug overdose mortality among PWUD with a particular focus on those facing these infections. Additionally, we will quantify the effect of MOUD on increasing survival and improving health outcomes in PWUD with SSTIs and IE. Finally, the project will examine disparities in MOUD by race, ethnicity, and gender. The project will utilize an extensive dataset of healthcare records for over half of North Carolinians linked with death certificate data. The specific aims of this study are to (1) assess predictors of infection-related mortality and drug overdose among PWUD, (2) estimate the effect of MOUD on infection-related mortality and drug overdose mortality among PWUD diagnosed with SSTIs or IE, and (3) examine receipt of MOUD and continuation among PWUD diagnosed with SSTIs or IE by race, ethnicity, and gender. Accompanying the proposed research, a specialized training plan for the principal investigator will enhance her skill set in: (1) study design of drug use-related health outcomes, (2) robust methodological approaches to the use of administrative data in translational research, and (3) professional development and research dissemination in scientific and community settings. Through the proposed research and mentorship from a multid...