Hand and Upper Extremity Infections in Intravenous Drug Users: Epidemiology and Predictors of Outcomes.

Purpose Injectable drug use (IDU) is a national epidemic, public health problem, and common cause of hand and upper extremity (UE) infections. This study assesses the epidemiology of the IDU patient population presenting to a Midwestern academic medical center emergency department (ED) and examines predictors influencing morbidity and outcomes. Methods A retrospective review was performed using International Classification of Diseases, Ninth Revision (ICD-9) codes to identify all adult patients presenting to the ED with hand/UE infections, with and without concurrent IDU diagnoses, over a period of 2.5 years. Demographics and clinical factors were examined utilizing bivariate and multivariable analyses to identify predictors of outcomes, including not completing outpatient follow-up and leaving against medical advice (AMA). Results A total of 1,482 patients with 1,754 ED visits for hand/UE infections were identified, including 308 patients with IDU-acquired infections (396 visits) and 1,174 patients with nonIDU infections (1,358 visits). Psychiatric comorbidities and hepatitis C were common in the IDU group (51% and 39%, respectively), and 31% of IDU patients were uninsured. Heroin use was identified in 96% of visits. The IDU infections were more likely to have surgical intervention than those in non-IDU patients (16% vs 6%), and a longer mean length hospital stay (2.4 vs 0.9 days). The IDU patients were more likely than non-IDU patients to leave AMA. In multivariable analysis, IDU, psychiatric comorbidity, and insurance status were independent predictors (P <.05) for leaving AMA. Conclusions In the setting of a national epidemic, hand/UE infections due to IDU are a common problem seen by hand surgeons. This study characterizes the growing IDU patient population at an urban academic medical center, examining the largest cohort of these patients to date. Copyright (C) 2020 by the American Society for Surgery of the Hand. All rights reserved.