Endocarditis, drug use and biological sex: A statewide analysis comparing sex differences in drug use-associated infective endocarditis with other drug-related harms

Objectives: Hospitalizations for drug use-associated infective endocarditis (DUA-IE) have risen sharply across the United States over the past decade. The sex composition of DUA-IE remains less clear, and studies have indicated a possible shift to more females. We aimed to compare more recent statewide hospitalization rates for DUA-IE in females versus males and contextualize them among other drug-related harms in North Carolina (NC). Methods: This study was a retrospective analysis using public health datasets of all NC hospital discharges for infective endocarditis from 2016 to 2020. Drug use-related hospitalizations were identified using ICD-10-CM codes. Discharge rates by year and sex for DUA-IE and non-DUA-IE were calculated and compared to fatal overdoses and acute hepatitis C (HCV). Temporal, demographic, and pregnancy trends were also assessed. Results: Hospitalizations rates for DUA-IE were 9.7 per 100,000 over the five-year period, and 1.2 times higher among females than males. Females composed 57% of DUA-IE hospitalizations over the period. Conversely, fatal overdose, acute HCV, and non-DUA-IE hospitalization rates were higher among males. Age, county of residence, and pregnancy status did not explain the higher DUA-IE among females. Conclusion: Females now comprise the majority of DUA-IE hospitalizations in NC, unlike other drug-related harms. No clear demographic or geographic associations were found, and further research is needed to explain this phenomenon. Preventing invasive infections among females who inject drugs should be prioritized.