Risk Factors for Infective Endocarditis and Serious Injection Related Infections Among People Who Inject Drugs in Los Angeles, CA and Denver, CO

Abstract

Background

Injection drug use-related infective endocarditis (IDU-IE) and bacterial infections have grown in the United States, but little is known about risk factors for these infections in community samples of people who inject drugs (PWID).

Methods

During 2021–22, PWID were recruited from community settings and surveyed for history of IDU-IE, serious injection related symptoms (SIRI) and untreated infection symptoms in the last 3 months. We used bivariate analysis and multiple logistic regression to examine factors associated with these outcomes.

Results

Among participants (n = 472), 7 % reported ever having IDU-IE, 14 % reported having SIRI symptoms and 20 % reported untreated infection symptoms in the last 3 months. Ever having IDU-IE was associated with HCV (adjusted odds ratio [AOR]=8.37; 95 % confidence interval [CI]=2.46, 28.49), prior MRSA infection (AOR=5.37; 95 % CI=2.44, 11.80), identifying as female and/or gender minority person (AOR=3.14; 95 % CI=1.42, 6.95). SIRI symptoms were associated with greater material hardship (compared to low; AOR=2.47; 95 % CI=1.17, 5.22), fentanyl use (AOR=2.15; 95 % CI=1.01, 4.61), sharing filter/cotton (AOR=1.93; 95 % CI=1.10, 3.39), and licking needle prior to injection (AOR=1.85; 95 % CI=1.02, 3.36). Untreated infection symptoms were associated with poor quality sleep (AOR=2.04; 95 % CI=1.21, 3.43), any mental health diagnoses (AOR=2.01; 95 % CI=3.56), any chronic pain (AOR=1.89; 95 % CI=1.14, 3.11), sharing filters (AOR=1.81; 95 % CI=1.10, 2.98), and prior MRSA infection (AOR=1.75; 95 % CI=1.04, 2.97).

Conclusion

Risk factors identified include treatable co-morbidities (i.e., HCV & MRSA history, mental health, pain, opioid use), modifiable health behaviors (i.e., equipment sharing, needle-licking), and addressable structural conditions (material hardship, housing).