(6) Racial Disparities in MOUD Initiation Among Medicaid Patients with Infective Endocarditis

Background & Introduction: People with injection drug use (IDU) have an increased risk of developing infective endocarditis (IE) and often have negative health outcomes, long hospitalizations, and incur high cost. Medication for opioid use disorder (MOUD) is associated with improved outcomes among people with IDU-IE. There is limited knowledge regarding the role of race and ethnicity in the initiation of MOUD among patients with IDU-IE. We aimed to identify racial and ethnic disparities in MOUD initiation among patients with IDU-IE and in outcomes of IDU-IE.

Methods: We used the T-MSIS Analytic File from 2017-2020, which includes Medicaid claims from all 50 states and Washington DC. We included patients aged 18-65 who were not dually-enrolled with Medicare, with at least one hospitalization for IE, defined using ICD-10 code. IDU-IE was defined using a combination of ICD-10 codes and medication codes related to injectable drug use. MOUD initiation was defined as the population with IDU initiated on MOUD within 30 and 90 days of admission and who had not been on MOUD in the six months prior to admission. Race and ethnicity were assigned based on the original dataset. We present descriptive analyses and results of logistic regression for binary outcomes.

Results: We identified 21,573 patients with IDU-IE, of which 9% were Black, 8% were Hispanic, and 67% were White. Six-month mortality among the cohort of patients with IDU-IE was 10%. Black patients with IDU-IE had the highest mortality rate, with significantly higher mortality compared to White patients (13.4% vs 9.5%, p< 0.001). Adjusting for age and sex attenuated the relationship between Black race and six-month mortality (OR 1.06, p-value 0.42). Black patients and non-Black Hispanic patients were significantly less likely to be initiated on MOUD at 90 days (OR 0.74 p=0.002 and OR 0.78 p =0.01 respectively). Younger patients (18y-29y) were significantly more likely to be initiated on MOUD than older patients (50y-65y) (16% vs 9%, p< 0.001). When adjusted for age and sex, Black race and non-Black Hispanic race continue to predict poor rates of initiation on MOUD (OR 0.82 p=0.05, OR 0.81 p< 0.03). Among patients with IDU-IE, patients initiated on MOUD had significantly lower mortality at 6 months after discharge compared to patients who were not initiated on MOUD (OR 0.28, p < 0.001). This effect persisted after adjusting for race, sex, and age (OR 0.29, p< 0.001).

Conclusion & Discussion: There are racial-ethnic disparities in MOUD initiation among Medicaid-insured patients with IDU-IE. Black race and non-Black Hispanic race are associated with lower rates of MOUD initiation, independently of other demographic factors. MOUD initiation is associated with improved survival among patients with IDU-IE. Racial and ethnic disparities in the initiation of MOUD can contribute to poorer outcomes associated with IDU-IE among Black and Hispanic patients. Further efforts are necessary to mitigate disparities in MOUD initiation among this population.

References:

Barocas, J. A., Morgan, J. R., Wang, J., McLoone, D., Wurcel, A., & Stein, M. D. (2021). Outcomes associated with medications for opioid use disorder among persons hospitalized for infective endocarditis. Clinical Infectious Diseases, 72(3), 472-478.

Kimmel, S. D., Walley, A. Y., Li, Y., Linas, B. P., Lodi, S., Bernson, D., ... & Larochelle, M. R. (2020). Association of treatment with medications for opioid use disorder with mortality after hospitalization for injection drug use–associated infective endocarditis. JAMA network open, 3(10), e2016228-e2016228.

Krawczyk, N., Feder, K. A., Fingerhood, M. I., & Saloner, B. (2017). Racial and ethnic differences in opioid agonist treatment for opioid use disorder in a US national sample. Drug and alcohol dependence, 178, 512-518.