Not Just Endocarditis: Hospitalizations for Selected Invasive Infections Among Persons With Opioid and Stimulant Use Diagnoses-North Carolina, 2010-2018

Long-term Risk of Serious Infections and Mortality Among Patients Surviving Drug Use-Associated Infective Endocarditis

Among a statewide cohort of 1874 patients surviving hospitalization for drug use-associated endocarditis during 2017-2020, the 3-year risk of death or future hospitalization was 38% (16% for death before later infection, 14% for recurrent endocarditis, 14% for soft tissue, 9% for bacteremia, 5% for bone/joint, and 4% for spinal infections).

Question-answering system extracts information on injection drug use from clinical notes

BACKGROUND

Injection drug use (IDU) can increase mortality and morbidity. Therefore, identifying IDU early and initiating harm reduction interventions can benefit individuals at risk. However, extracting IDU behaviors from patients' electronic health records (EHR) is difficult because there is no other structured data available, such as International Classification of Disease (ICD) codes, and IDU is most often documented in unstructured free-text clinical notes. Although natural language processing can efficiently extract this information from unstructured data, there are no validated tools.

METHODS

To address this gap in clinical information, we design a question-answering (QA) framework to extract information on IDU from clinical notes for use in clinical operations. Our framework involves two main steps: (1) generating a gold-standard QA dataset and (2) developing and testing the QA model. We use 2323 clinical notes of 1145 patients curated from the US Department of Veterans Affairs (VA) Corporate Data Warehouse to construct the gold-standard dataset for developing and evaluating the QA model. We also demonstrate the QA model's ability to extract IDU-related information from temporally out-of-distribution data.

RESULTS

Here, we show that for a strict match between gold-standard and predicted answers, the QA model achieves a 51.65% F1 score. For a relaxed match between the gold-standard and predicted answers, the QA model obtains a 78.03% F1 score, along with 85.38% Precision and 79.02% Recall scores. Moreover, the QA model demonstrates consistent performance when subjected to temporally out-of-distribution data.

CONCLUSIONS

Our study introduces a QA framework designed to extract IDU information from clinical notes, aiming to enhance the accurate and efficient detection of people who inject drugs, extract relevant information, and ultimately facilitate informed patient care.

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.

Medications for Opioid Use Disorder and Mortality and Hospitalization Among People With Opioid Use-related Infections

BACKGROUND

Severe skin and soft tissue infections related to injection drug use have increased in concordance with a shift to heroin and illicitly manufactured fentanyl. Opioid agonist therapy medications (methadone and buprenorphine) may improve long-term outcomes by reducing injection drug use. We aimed to examine the association of medication use with mortality among people with opioid use-related skin or soft tissue infections.

METHODS

An observational cohort study of Medicaid enrollees aged 18 years or older following their first documented medical encounters for opioid use-related skin or soft tissue infections during 2007-2018 in North Carolina. The exposure was documented medication use (methadone or buprenorphine claim) in the first 30 days following initial infection compared with no medication claim. Using Kaplan-Meier estimators, we examined the difference in 3-year incidence of mortality by medication use, weighted for year, age, comorbidities, and length of hospital stay.

RESULTS

In this sample, there were 13,286 people with opioid use-related skin or soft tissue infections. The median age was 37 years, 68% were women, and 78% were white. In Kaplan-Meier curves for the total study population, 12 of every 100 patients died during the first 3 years. In weighted models, for every 100 people who used medications, there were four fewer deaths over 3 years (95% confidence interval = 2, 6).

CONCLUSION

In this study, people with opioid use-related skin and soft tissue infections had a high risk of mortality following their initial healthcare visit for infections. Methadone or buprenorphine use was associated with reductions in mortality.

Epidemiology of acute infections in people who inject drugs in Australia

ISSUES

People who inject drugs are at risk of acute infections, such as skin and soft tissue infections, infective endocarditis, bone and joint infections and bloodstream infections. There has been an increase in these infections in people who inject drugs internationally over the past 10 years. However, the local data regarding acute infections in Australia has not been well described.

APPROACH

We review the epidemiology of acute infections and associated morbidity and mortality amongst people who inject drugs in Australia. We summarise risk factors for these infections, including the concurrent social and psychological determinants of health.

KEY FINDINGS

The proportion of people who report having injected drugs in the prior 12 months in Australia has decreased over the past 18 years. However, there has been an increase in the burden of acute infections in this population. This increase is driven largely by skin and soft tissue infections. People who inject drugs often have multiple conflicting priorities that can delay engagement in care.

IMPLICATIONS

Acute infections in people who inject drugs are associated with significant morbidity and mortality. Acute infections contribute to significant bed days, surgical requirements and health-care costs in Australia. The increase in these infections is likely due to a complex interplay of microbiological, individual, social and environmental factors.

CONCLUSION

Acute infections in people who inject drugs in Australia represent a significant burden to both patients and health-care systems. Flexible health-care models, such as low-threshold wound clinics, would help directly target, and address early interventions, for these infections.

Mortality associated with bacterial and fungal infections and overdose among people with drug use diagnoses

PURPOSE

Hospital visits for drug use-related bacterial and fungal infections have increased alongside overdose deaths. The incidence of mortality from these infections and the comparison to overdose mortality is not established.

METHODS

This cohort study examined mortality outcomes among adults with drug use diagnoses who were insured by public and private plans during 2007 through 2018 in North Carolina. We examined bacterial- and fungal infection-related mortality and overdose mortality using cumulative incidence functions.

RESULTS

Among 131,522 people with drug use diagnoses, the median age was 45 years (interquartile range: 31-57), 58% were women and 65% had an opioid use disorder diagnosis. The 1-year incidence of bacterial and fungal infection-associated mortality was progressively higher as age increased (35-49 years: 9 per 10,000 people, 50-64 years: 23 per 10,000, 65+ years: 50 per 10,000 people). Conversely, the 1-year incidence of overdose mortality was markedly lower among older adults compared to those under the age of 65 (18-34 years: 34 deaths per 10,000 people; 35-49 years: 47 per 10,000; 50-64 years: 41 per 10,000; 65+ years: 9 per 10,000).

CONCLUSIONS

Bacterial and fungal infections and overdose were notable causes of death among adults with drug use diagnoses, and varied by age group.

A Study Protocol to Increase Engagement in Evidence Based Hospital and Community Based Care Using a Serious Injection Related Infections (SIRI) Checklist and Enhanced Peer for Hospitalized PWID (ShaPe)

Background

With the opioid crisis, surging methamphetamine use, and healthcare disruptions due to SARS-CoV-2, serious injection related infections (SIRIs), like endocarditis, have increased significantly. Hospitalizations for SIRI provide a unique opportunity for persons who inject drugs (PWID) to engage in addiction treatment and infection prevention, yet many providers miss opportunities for evidence-based care due to busy inpatient services and lack of awareness. To improve hospital care, we developed a 5-item SIRI Checklist for providers as a standardized reminder to offer medication for opioid use disorder (MOUD), HIV and HCV screening, harm reduction counseling, and referral to community-based care. We also formalized an Intensive Peer Recovery Coach protocol to support PWID on discharge. We hypothesized that the SIRI Checklist and Intensive Peer Intervention would increase use of hospital-based services (HIV, HCV screening, MOUD) and linkage to community-based care: PrEP prescription, MOUD prescription, and related outpatient visit(s).

Methods

This is a feasibility study and randomized control trial of a checklist and intensive peer intervention for hospitalized PWID with SIRI admitted to UAB Hospital. We will recruit 60 PWID who will be randomized to one of 4 groups (SIRI Checklist, SIRI Checklist + Enhanced Peer, Enhanced Peer, and Standard of Care). Results will be analyzed using a 2x2 factorial design. We will use surveys to collect data on drug use behaviors, stigma, HIV risk, and PrEP interest and awareness. Our primary outcome of feasibility will include the ability to recruit hospitalized PWID and retain them in the study to determine post-discharge clinical outcomes. Additionally, we will explore clinical outcomes using a combination of patient surveys and electronic medical record data (HIV, HCV testing, MOUD and PrEP prescriptions).This study is approved by UAB IRB #300009134.

Discussion

This feasibility study is a necessary step in designing and testing patient-centered interventions to improve public health for rural and Southern PWID. By testing low barrier interventions that are accessible and reproducible in states without access to Medicaid expansion and robust public health infrastructure, we aim to identify models of care that promote linkage and engagement in community care.

Trial Registration

NCT05480956.

Epidemiology and Management of invasive infections among people who Use drugs (EMU): protocol for a prospective, multicentre cohort study

INTRODUCTION

People who inject drugs (PWID) are at risk of invasive infections such as bloodstream infections, endocarditis, osteomyelitis and septic arthritis. Such infections require prolonged antibiotic therapy, but there is limited evidence about the optimal care model to deliver to this population. The Epidemiology and Management of invasive infections among people who Use drugs (EMU) study aims to (1) describe the current burden, clinical spectrum, management and outcomes of invasive infections in PWID; (2) determine the impact of currently available models of care on completion of planned antimicrobials for PWID admitted to hospital with invasive infections and (3) determine postdischarge outcomes of PWID admitted with invasive infections at 30 and 90 days.

METHODS AND ANALYSIS

EMU is a prospective multicentre cohort study of Australian public hospitals who provide care to PWIDs with invasive infections. All patients who have injected drugs in the previous six months and are admitted to a participating site for management of an invasive infection are eligible. EMU has two components: (1) EMU-Audit will collect information from medical records, including demographics, clinical presentation, management and outcomes; (2) EMU-Cohort will augment this with interviews at baseline, 30 and 90 days post-discharge, and data linkage examining readmission rates and mortality. The primary exposure is antimicrobial treatment modality, categorised as inpatient intravenous antimicrobials, outpatient antimicrobial therapy, early oral antibiotics or lipoglycopeptide. The primary outcome is confirmed completion of planned antimicrobials. We aim to recruit 146 participants over a 2-year period.

ETHICS AND DISSEMINATION

EMU has been approved by the Alfred Hospital Human Research Ethics Committee (Project number 78815.) EMU-Audit will collect non-identifiable data with a waiver of consent. EMU-Cohort will collect identifiable data with informed consent. Findings will be presented at scientific conferences and disseminated by peer-review publications.

TRIAL REGISTRATION NUMBER

ACTRN12622001173785; Pre-results.

Outcomes of Partial Oral Antibiotic Treatment for Complicated Staphylococcus aureus Bacteremia in People Who Inject Drugs

BACKGROUND

Staphylococcus aureus represents the leading cause of complicated bloodstream infections among persons who inject drugs (PWID). Standard of care (SOC) intravenous (IV) antibiotics result in high rates of treatment success but are not feasible for some PWID. Transition to oral antibiotics may represent an alternative treatment option.

METHODS

We evaluated all adult patients with a history of injection drug use hospitalized from January 2016 through December 2021 with complicated S. aureus bloodstream infections, including infective endocarditis, epidural abscess, vertebral osteomyelitis, and septic arthritis. Patients were compared by antibiotic treatment (standard of care intravenous [SOC IV] antibiotics, incomplete IV therapy, or transition from initial IV to partial oral) using the primary composite endpoint of death or readmission from microbiologic failure within 90 days of discharge.

RESULTS

Patients who received oral antibiotics after an incomplete IV antibiotic course were significantly less likely to experience microbiologic failure or death than patients discharged without oral antibiotics (P < .001). There was no significant difference in microbiologic failure rates when comparing patients who were discharged on partial oral antibiotics after receiving at least 10 days of IV antibiotics with SOC regimens (P > .9).

CONCLUSIONS

Discharge of PWID with partially treated complicated S. aureus bacteremias without oral antibiotics results in high rates of morbidity and should be avoided. For PWID hospitalized with complicated S. aureus bacteremias who have received at least 10 days of effective IV antibiotic therapy after clearance of bacteremia, transition to oral antibiotics with outpatient support represents a potential alternative if the patient does not desire SOC IV antibiotic therapy.

"They Just Assume That We're All Going to Do the Wrong Thing With It. It's Just Not True": Stakeholder Perspectives About Peripherally Inserted Central Catheters in People Who Inject Drugs

Background

In the absence of adequate harm reduction opportunities, people who inject drugs (PWID) are at increased risk for serious infections. Infectious diseases guidelines recommend extended periods of intravenous antibiotic treatment through peripherally inserted central catheters (PICCs), but PWID are often deemed unsuitable for this treatment. We conducted semi-structured interviews and focus groups to understand the perspectives and opinions of patients and clinicians on the use of PICCs for PWID.

Methods

We approached patients and clinicians (doctors, nurses, PICC nurses, social workers, and case workers) involved in patient care at Tufts Medical Center (Boston, Massachusetts) between August 2019 and April 2020 for semi-structured interviews and focus groups.

Results

Eleven of 14 (79%) patients agreed to participate in an in-depth interview, and 5 role-specific clinician focus groups (1 group consisting of infectious diseases, internal medicine, and addiction psychiatry doctors, 2 separate groups of floor nurses, 1 group of PICC nurses, and 1 group of social workers) were completed. Emergent themes included the overall agreement that PICCs improve healthcare, patients' feelings that their stage of recovery from addiction was not taken into consideration, and clinicians' anecdotal negative experiences driving decisions on PICCs.

Conclusions

When analyzed together, the experiences of PWID and clinicians shed light on ways the healthcare system can improve the quality of care for PWID hospitalized for infections. Further research is needed to develop a system of person-centered care for PWID that meets the specific needs of patients and improves the relationship between them and the healthcare system.

The practice and embodiment of "goofballs": A qualitative study exploring the co-injection of methamphetamines and opioids

BACKGROUND

Polysubstance use is common among people who use drugs, including the co-use of stimulants and opioids. Research suggests the practice of simultaneous co-injection of methamphetamines and opioids, often referred to as "goofballs", is increasing. As a relatively unique drug use practice, little qualitative research currently exists on goofball injecting. This study explores the practice and embodied experiences of goofball injecting.

METHODS

This article draws on in-depth interviews conducted across two qualitative studies undertaken in Vancouver, Canada's Downtown Eastside neighbourhood examining changing dynamics in relation to stimulant use and experiences with an overdose prevention site-based safer supply intervention, respectively. Interviews containing discussions of goofball use (n=29) were extracted from each study and merged into a single qualitative dataset. Data were analysed thematically and focused on the practices and embodied experiences of goofball injection.

RESULTS

Our analysis uncovered how goofball injection represented a complex drug use practice driven by the desire to achieve particular embodied experiences not attainable by using either drug individually. We identified three distinct practices of goofball use: 1) to alter or enhance the effects of opioids; 2) to alter or enhance the effects of methamphetamines; and 3) to balance out the effects of both drugs.

CONCLUSION

Our study fills an important gap in the polysubstance use literature specifically exploring the co-injection of methamphetamines and opioids. Our findings highlight the need to implement and expand interventions and services attentive to polysubstance use and the role of pleasure in drug taking practices, including expanding non-medicalized opioid and stimulant safer supply initiatives across North America.

Natural Language Processing and Machine Learning to Identify People Who Inject Drugs in Electronic Health Records

Background

Improving the identification of people who inject drugs (PWID) in electronic medical records can improve clinical decision making, risk assessment and mitigation, and health service research. Identification of PWID currently consists of heterogeneous, nonspecific International Classification of Diseases (ICD) codes as proxies. Natural language processing (NLP) and machine learning (ML) methods may have better diagnostic metrics than nonspecific ICD codes for identifying PWID.

Methods

We manually reviewed 1000 records of patients diagnosed with Staphylococcus aureus bacteremia admitted to Veterans Health Administration hospitals from 2003 through 2014. The manual review was the reference standard. We developed and trained NLP/ML algorithms with and without regular expression filters for negation (NegEx) and compared these with 11 proxy combinations of ICD codes to identify PWID. Data were split 70% for training and 30% for testing. We calculated diagnostic metrics and estimated 95% confidence intervals (CIs) by bootstrapping the hold-out test set. Best models were determined by best F-score, a summary of sensitivity and positive predictive value.

Results

Random forest with and without NegEx were the best-performing NLP/ML algorithms in the training set. Random forest with NegEx outperformed all ICD-based algorithms. F-score for the best NLP/ML algorithm was 0.905 (95% CI, .786-.967) and 0.592 (95% CI, .550-.632) for the best ICD-based algorithm. The NLP/ML algorithm had a sensitivity of 92.6% and specificity of 95.4%.

Conclusions

NLP/ML outperformed ICD-based coding algorithms at identifying PWID in electronic health records. NLP/ML models should be considered in identifying cohorts of PWID to improve clinical decision making, health services research, and administrative surveillance.

Trends and characteristics of primary pyogenic spine infections among people who do and do not inject drugs: Northeast New York State, 2007 to 2018

Background:

Pyogenic spine infections (PSIs) are challenging to diagnose and treat. People who inject drugs (PWID) are at increased risk and contribute to rising PSI incidence.

Objective:

To analyze trends and characterize PSI in persons who do and do not inject drugs in northeast New York State (NYS), a predominantly rural region.

Methods:

A retrospective study of PSI patients at a regional tertiary care hospital from 2007 to 2018 was conducted. PSI incidence, population demographics, microbiology, surgical interventions, length of stay (LOS), and costs were compared between injection substance use disorder (ISUD) and non-ISUD cohorts.

Results:

Two hundred and seventy patients (59 ISUD and 211 non-ISUD) were included in this study. PSI incidence due to ISUD increased 1175% during the study time periods. The median age of the ISUD and non-ISUD cohorts was 39 and 65, respectively. Staphylococcus aureus was the most common causative organism, although a variety of bacterial and fungal pathogens were identified. Nearly half of the patients in each cohort required surgical intervention. Median acute care LOS was 12 days and comparable between cohorts. However, the ISUD cohort was frequently discharged against medical advice, or transferred back to acute care hospitals to complete antibiotic courses. Median inpatient hospital costs were approximately $25,000 and were comparable between cohorts. These costs do not reflect inpatient costs once the patient was transferred back to the referring hospital, nor costs for outpatient care. Medicaid and Medicare were the most common primary insurance payers for the ISUD and non-ISUD cohorts, respectively.

Conclusions:

Incidence of PSI has increased significantly coincident with the opioid epidemic and has had significant impact on a large, rural region of NYS. PSIs consume large amounts of healthcare resources. This study can inform hospitals and public health agencies regarding the need for substance abuse harm reduction strategies.

Comparative 1-Year Outcomes of Invasive Staphylococcus aureus Infections Among Persons With and Without Drug Use: An Observational Cohort Study

BACKGROUND

Persons who use drugs (PWUD) face substantial risk of Staphylococcus aureus infections. Limited data exist describing clinical and substance use characteristics of PWUD with invasive S. aureus infections or comparing treatment and mortality outcomes in PWUD vs non-PWUD. These are needed to inform optimal care for this marginalized population.

METHODS

We identified adults hospitalized from 2013 to 2018 at 2 medical centers in San Francisco with S. aureus bacteremia or International Classification of Diseases-coded diagnoses of endocarditis, epidural abscess, or vertebral osteomyelitis with compatible culture. In addition to demographic and clinical characteristic comparison, we constructed multivariate Cox proportional hazards models for 1-year infection-related readmission and mortality, adjusted for age, race/ethnicity, housing, comorbidities, and methicillin-resistant S. aureus (MRSA).

RESULTS

Of 963 hospitalizations for S. aureus infections in 946 patients, 372 of 963 (39%) occurred in PWUD. Among PWUD, heroin (198/372 [53%]) and methamphetamine use (185/372 [50%]) were common. Among 214 individuals using opioids, 98 of 214 (46%) did not receive methadone or buprenorphine. PWUD had lower antibiotic completion than non-PWUD (70% vs 87%; P < .001). While drug use was not associated with increased mortality, 1-year readmission for ongoing or recurrent infection was double in PWUD vs non-PWUD (28% vs 14%; adjusted hazard ratio [aHR], 2.0 [95% confidence interval {CI}: 1.3-2.9]). MRSA was independently associated with 1-year readmission for infection (aHR, 1.5 [95% CI: 1.1-2.2]).

CONCLUSIONS

Compared to non-PWUD, PWUD with invasive S. aureus infections had lower rates of antibiotic completion and twice the risk of infection persistence/recurrence at 1 year. Among PWUD, both opioid and stimulant use were common. Models for combined treatment of substance use disorders and infections, particularly MRSA, are needed.

Treatment experiences for skin and soft tissue infections among participants of syringe service programs in North Carolina

INTRODUCTION

Bacterial and fungal infections, such as skin and soft tissue infections (SSTIs) and infective endocarditis (IE), are increasing among people who use drugs in the United States. Traditional healthcare settings can be inaccessible and unwelcoming to people who use drugs, leading to delays in getting necessary care. The objective of this study was to examine SSTI treatment experiences among people utilizing services from syringe services programs. This study was initiated by people with lived experience of drug use to improve quality of care.

METHODS

We conducted a cross-sectional survey among participants of five syringe services programs in North Carolina from July through September 2020. Surveys collected information on each participant's history of SSTIs and IE, drug use and healthcare access characteristics, and SSTI treatment experiences. We examined participant characteristics using counts and percentages. We also examined associations between participant characteristics and SSTI history using binomial linear regression models.

RESULTS

Overall, 46% of participants reported an SSTI in the previous 12 months and 10% reported having IE in the previous 12 months. Those with a doctor they trusted with drug use-related concerns had 27 fewer (95% confidence interval = - 51.8, - 2.1) SSTIs per every 100 participants compared to those without a trusted doctor. Most participants with a SSTI history reported delaying (98%) or not seeking treatment (72%) for their infections. Concerns surrounding judgment or mistreatment by medical staff and self-treating the infection were common reasons for delaying or not seeking care. 13% of participants used antibiotics obtained from sources other than a medical provider to treat their most recent SSTI. Many participants suggested increased access to free antibiotics and on-site clinical care based at syringe service programs to improve treatment for SSTIs.

CONCLUSIONS

Many participants had delayed or not received care for SSTIs due to poor healthcare experiences. However, having a trusted doctor was associated with fewer people with SSTIs. Improved access to non-judgmental healthcare for people who use drugs with SSTIs is needed. Expansion of syringe services program-based SSTI prevention and treatment programs is likely a necessary approach to improve outcomes among those with SSTI and IE.