# Inpatient addiction care is associated with increased vaccinations, medication for opioid use disorder and naloxone prescribing among patients with infective endocarditis in a rural state

## TL;DR

Inpatient addiction care in a rural hospital improved vaccination rates and opioid treatment for patients with drug-related heart infections.

## Contribution

Shows inpatient addiction services increase MOUD, naloxone, and vaccinations for IDU-related endocarditis in rural areas.

## Key findings

- MOUD prescribing increased from 8% to 80% after IMAT implementation.
- Tdap vaccination rates rose from 7.3% to 41% following the program.
- Hepatitis A and B vaccination rates also increased significantly.

## Abstract

Rural states have experienced increasing injection drug use (IDU)-associated infective endocarditis (IE). Inpatient addiction consult services can reduce morbidity associated with substance use and other infectious complications, such as IDU-IE. However data on the impact of such services on healthcare utilization are limited, particularly in rural communities.

This retrospective study assesses clinical and health service utilization data from index hospitalizations for IDU-IE before and after the implementation of the Integrated Medication for Addiction Treatment (IMAT) program at a tertiary care center in a rural state. We summarized data descriptively, stratified by both pre- and post-IMAT program implementation and IDU-IE and non-IDU IE. We also performed exploratory multivariable analyses assessing the association between IMAT program implementation and various outcomes. The primary outcomes were: 1) 90-day emergency department (ED) visits and 2) 30-day hospital readmissions post-discharge. Secondary outcomes included prescriptions at time of discharge for medication for opioid use disorder (MOUD), naloxone and key vaccinations.

We identified n = 99 patients with IDU-IE. Comparing pre- and post-IMAT implementation, 30-day readmissions trended lower post-IMAT (18%) versus pre-IMAT (22%), although the difference was not significant (p = 0.7). 90-day ED visits remained stable (37%, p > 0.9). The proportion of MOUD prescribing (24% versus 80%), hepatitis B vaccination (29% versus 51%), and Tdap vaccination (7.3% versus 41%) increased significantly following IMAT implementation (p < 0.001, p = 0.037 and p < 0.001, respectively). In a regression analysis controlling for age, housing status, primary care provider, age, hepatitis C, cardiac device, Duke’s criteria, valve affected, alcohol use disorder, payer, and vascular or infectious complications, the IMAT program was not significantly associated with the primary outcomes or with hepatitis B vaccination. However, the IMAT program was associated with increased MOUD prescribing (aOR: 110; CI:16–1500), naloxone prescribing (aOR 18; CI: 1.1–1600) hepatitis A vaccination (aOR: 5.3; CI: 1.2–32), and Tdap vaccination (aOR: 9.2; CI: 2.0–59).

Inpatient addiction services were associated with increased prescribing of MOUD, naloxone and key vaccinations, though the incidence of acute healthcare utilization did not change. These results highlight hospitalization as an opportunity to connect patients with IDU-IE to MOUD and preventative care, particularly in rural areas where access to such services may be limited.

Not applicable.

The online version contains supplementary material available at 10.1186/s13722-025-00614-6.