# Incidence, Patient-Directed Discharge, Readmission, and Mortality Among People Hospitalized With Injecting-Related Infection: A Population-Based Linkage Study

## TL;DR

This study examines hospitalizations for injecting-related infections among people who inject drugs in Australia, finding high readmission rates and identifying factors linked to patient discharge and mortality.

## Contribution

The study provides a large-scale population-based analysis of injecting-related infection outcomes and correlates of patient discharge and readmission.

## Key findings

- Injecting-related infection hospitalizations increased over time, with an incidence of 47.2 per 100 person-years.
- Patient-directed discharge was associated with stimulant use and incarceration, and linked to higher readmission rates.
- Mortality was 2% at 30 days and 15% at 1 year post-discharge, with readmission rates as high as 61% within a year.

## Abstract

Despite increasing hospitalization for injecting-related infection, there has been limited large-scale evaluation of in-hospital and post-discharge outcomes. This study aimed to characterize population-level injecting-related infection hospitalization and correlates associated with patient-directed discharge, readmission, and all-cause mortality among persons who inject drugs with hepatitis C in New South Wales, Australia, between 2001 and 2022.

Hepatitis C notifications in New South Wales were linked to data involving hospitalizations, opioid agonist treatment, incarceration, and death registration. Hospitalizations among people who inject drugs with injecting-related infections were identified by ICD-10 code algorithms. Incidence of patient-directed discharge, readmission, and mortality was calculated, and correlates associated with each outcome were assessed by extension of a Cox proportional hazards model for recurrent events.

In total, 18074 injecting-related infection hospitalizations were included among 9045 individuals, predominantly males (64%) with an average age of 41 years. The incidence was 47.2 per 100 person-years and increased over time. The proportion of hospitalizations ending in patient-directed discharge was 18% and was associated with stimulant use and incarceration, and lower in those with severe disease and opiate agonist therapy. The proportions of hospitalizations that were followed by 30-day and 1-year readmission were 25% and 61%, respectively, and had a strong association with patient-directed discharge. Mortality was 2% at 30 days and 15% at 1 year post-discharge.

Patient-directed discharge was common among people admitted with injecting-related infections and was associated with readmission but not mortality. Person-centered models of care are necessary to address the health inequity experienced by people who inject drugs.

In this large-scale data linkage analysis that characterized injecting-related infections, the incidence increased, and patient-directed discharge was common, leading to high readmission rates. Other factors were explored to identify patients at highest risk for poor outcomes and target interventions.

Graphical AbstractThis graphical abstract is also available at Tidbit: https://tidbitapp.io/tidbits/incidence-patient-directed-discharge-readmission-and-mortality-among-people-hospitalized-with-injecting-related-infection-a-population-based-linkage-study?utm_campaign=tidbitlinkshare&utm_source=ITP

This graphical abstract is also available at Tidbit: https://tidbitapp.io/tidbits/incidence-patient-directed-discharge-readmission-and-mortality-among-people-hospitalized-with-injecting-related-infection-a-population-based-linkage-study?utm_campaign=tidbitlinkshare&utm_source=ITP