Frequency, factors and costs associated with injection site infections: findings from a national multi-site survey of injecting drug users in England

Economic evaluation of the effect of needle and syringe programs on skin, soft tissue, and vascular infections in people who inject drugs: a microsimulation modelling approach

BACKGROUND

Needle and syringe programs (NSP) are effective harm-reduction strategies against HIV and hepatitis C. Although skin, soft tissue, and vascular infections (SSTVI) are the most common morbidities in people who inject drugs (PWID), the extent to which NSP are clinically and cost-effective in relation to SSTVI in PWID remains unclear. The objective of this study was to model the clinical- and cost-effectiveness of NSP with respect to treatment of SSTVI in PWID.

METHODS

We performed a model-based, economic evaluation comparing a scenario with NSP to a scenario without NSP. We developed a microsimulation model to generate two cohorts of 100,000 individuals corresponding to each NSP scenario and estimated quality-adjusted life-years (QALY) and cost (in 2022 Canadian dollars) over a 5-year time horizon (1.5% per annum for costs and outcomes). To assess the clinical effectiveness of NSP, we conducted survival analysis that accounted for the recurrent use of health care services for treating SSTVI and SSTVI mortality in the presence of competing risks.

RESULTS

The incremental cost-effectiveness ratio associated with NSP was $70,278 per QALY, with incremental cost and QALY gains corresponding to $1207 and 0.017 QALY, respectively. Under the scenario with NSP, there were 788 fewer SSTVI deaths per 100,000 PWID, corresponding to 24% lower relative hazard of mortality from SSTVI (hazard ratio [HR] = 0.76; 95% confidence interval [CI] = 0.72-0.80). Health service utilization over the 5-year period remained lower under the scenario with NSP (outpatient: 66,511 vs. 86,879; emergency department: 9920 vs. 12,922; inpatient: 4282 vs. 5596). Relatedly, having NSP was associated with a modest reduction in the relative hazard of recurrent outpatient visits (HR = 0.96; 95% CI = 0.95-0.97) for purulent SSTVI as well as outpatient (HR = 0.88; 95% CI = 0.87-0.88) and emergency department visits (HR = 0.98; 95% CI = 0.97-0.99) for non-purulent SSTVI.

CONCLUSIONS

Both the individuals and the healthcare system benefit from NSP through lower risk of SSTVI mortality and prevention of recurrent outpatient and emergency department visits to treat SSTVI. The microsimulation framework provides insights into clinical and economic implications of NSP, which can serve as valuable evidence that can aid decision-making in expansion of NSP services.

Community-Acquired Staphylococcus aureus Bacteremia Among People Who Inject Drugs: A National Cohort Study in England, 2017-2020

BACKGROUND

People who inject drugs (PWID) are at increased risk of community-acquired Staphylococcus aureus bacteremia (CA-SAB), but little is known about clinical outcomes of CA-SAB in PWID compared with the wider population of patients with CA-SAB.

METHODS

Three national datasets were linked to provide clinical and mortality data on patients hospitalized with CA-SAB in England between 1 January 2017 and 31 December 2020. PWID were identified using the International Classification of Diseases, Tenth Revision code for "mental health and behavioral disorder due to opioid use" (F11). Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) for associations of PWID with 30-day all-cause mortality and 90-day hospital readmission.

RESULTS

In 10 045 cases of CA-SAB, 1612 (16.0%) were PWID. Overall, 796 (7.9%) patients died within 30 days of CA-SAB admission and 1189 (11.8%) patients were readmitted to hospital within 90 days of CA-SAB. In those without infective endocarditis, there was strong evidence of lower odds of mortality among PWID compared with non-PWID (aOR, 0.47 [95% confidence interval {CI}: .33-.68]; P < .001), whereas there was no association in CA-SAB case fatality with endocarditis (aOR, 1.40 [95% CI: .87-2.25]; P = .163). PWID were less likely to be readmitted within 90 days of CA-SAB (aOR, 0.79 [95% CI: .65-.95]; P = .011).

CONCLUSIONS

In this large cohort study of patients with CA-SAB in England, PWID had lower odds of death in the absence of endocarditis and lower odds of readmission within 90 days compared to non-PWID patients. This study highlights the overrepresentation of PWID among patients with CA-SAB nationally.

Staphylococcus aureus carriage and prevalence of skin and soft tissue infections among people who inject drugs: a longitudinal study

People who inject drugs are frequently colonized with Staphylococcus aureus and have an increased risk for skin and soft tissue infections. This longitudinal study aims to describe S. aureus carriage in this group and the risk for infections during a 1-year follow-up. We included 61 participants from the Malmö Needle Exchange Program. Mapping of S. aureus carriage was conducted by screening cultures every third month and S. aureus growth was semi-quantified. Data regarding infections and living conditions were collected from structured interviews. Statistics included univariate analysis with the Fischer's exact test, univariate logistic regression and multivariate logistic regression. S. aureus carriage was detected in 46-63% of participants, and 75% reported one or more infections during the study period. Self-reported infections were associated with carriage in perineum (OR 5.08 [95% CI 1.45-17.73]), in skin lesions (OR 1.48 [95% CI 1.21-1.81]), and unstable housing situation (OR 12.83 [95% CI 1.56-105.81]). Thus, people who inject drugs are frequent carriers of S. aureus and report a surprisingly high prevalence of skin and soft tissue infections. Homeless people and those with skin carriage seem to be at highest risk. Effective clinical interventions are needed, aiming at preventing infections in this vulnerable group.

Kentucky Outreach Service Kiosk (KyOSK) Study protocol: a community-level, controlled quasi-experimental, type 1 hybrid effectiveness study to assess implementation, effectiveness and cost-effectiveness of a community-tailored harm reduction kiosk on HIV, HCV and overdose risk in rural Appalachia

INTRODUCTION

Many rural communities bear a disproportionate share of drug-related harms. Innovative harm reduction service models, such as vending machines or kiosks, can expand access to services that reduce drug-related harms. However, few kiosks operate in the USA, and their implementation, impact and cost-effectiveness have not been adequately evaluated in rural settings. This paper describes the Kentucky Outreach Service Kiosk (KyOSK) Study protocol to test the effectiveness, implementation outcomes and cost-effectiveness of a community-tailored, harm reduction kiosk in reducing HIV, hepatitis C and overdose risk in rural Appalachia.

METHODS AND ANALYSIS

KyOSK is a community-level, controlled quasi-experimental, non-randomised trial. KyOSK involves two cohorts of people who use drugs, one in an intervention county (n=425) and one in a control county (n=325). People who are 18 years or older, are community-dwelling residents in the target counties and have used drugs to get high in the past 6 months are eligible. The trial compares the effectiveness of a fixed-site, staffed syringe service programme (standard of care) with the standard of care supplemented with a kiosk. The kiosk will contain various harm reduction supplies accessible to participants upon valid code entry, allowing dispensing data to be linked to participant survey data. The kiosk will include a call-back feature that allows participants to select needed services and receive linkage-to-care services from a peer recovery coach. The cohorts complete follow-up surveys every 6 months for 36 months (three preceding kiosk implementation and four post-implementation). The study will test the effectiveness of the kiosk on reducing risk behaviours associated with overdose, HIV and hepatitis C, as well as implementation outcomes and cost-effectiveness.

ETHICS AND DISSEMINATION

The University of Kentucky Institutional Review Board approved the protocol. Results will be disseminated in academic conferences and peer-reviewed journals, online and print media, and community meetings.

TRIAL REGISTRATION NUMBER

NCT05657106.

Evidence of telescoping in females across two decades of US treatment admissions for injection drug use: 2000-2020

Background

People who inject drugs (PWID) have an increased risk of soft tissue infection, drug overdose and death. Females may be particularly vulnerable due to barriers to substance use disorder (SUD) treatment entry, stigma, and telescoping, or the greater severity in substance use-related comorbidity and consequences despite a shorter history of use. We set out to identify sex differences in United States injection drug use (IDU).

Methods

The Treatment Episode Dataset-Admission (2000-2020) provided data to identify PWID undergoing their initial SUD treatment admission. Mann-Whitney U test, chi-square, and Spearman correlations were used for ordinal variables, categorical variables, and to assess similarity of male/female trends over the 21 years, respectively. The probabilistic index (PI) and Cramer's V provided effect sizes for Mann-Whitney U tests and chi-square tests, respectively.

Results

A total of 13,612,978 records existed for cases entering their initial treatment. Mapping to a history of IDU left 1,458,695 (561,793 females). Females had a higher prevalence among PWID across all 21 years; IDU trends were essentially identical between males and females (r = 0.97). Females endorsed beginning their primary substance later in life (PI = 0.47, p < 0.0001) and entered treatment after a shorter period of substance use (PI = 0.57, p < 0.0001).

Conclusions

We saw evidence of telescoping among PWID with a SUD entering their initial episode of treatment. Interventions should be implemented prior to the transition to IDU, and this window of opportunity is shortened in females. Utilizing gender-responsive treatment options may be a way to increase treatment-seeking earlier in the disease course.

Effect of incarceration and opioid agonist treatment transitions on risk of hospitalisation with injection drug use-associated bacterial infections: A self-controlled case series in New South Wales, Australia

BACKGROUND

Transitional times in opioid use, such as release from prison and discontinuation of opioid agonist treatment (OAT), are associated with health harms due to changing drug consumption practices and limited access to health and social supports. Using a self-controlled (within-person) study design, we aimed to understand if these transitions increase risks of injection drug use-associated bacterial infections.

METHODS

We performed a self-controlled case series among a cohort of people with opioid use disorder (who had all previously accessed OAT) in New South Wales, Australia, 2001-2018. The outcome was hospitalisation with injecting-related bacterial infections. We divided participants' observed days into time windows related to incarceration and OAT receipt. We compared hospitalization rates during focal (exposure) windows and referent (control) windows (i.e., 5-52 weeks continuously not incarcerated or continuously receiving OAT). We estimated adjusted incidence rate ratios (aIRR) using conditional logistic regression, adjusted for time-varying confounders.

RESULTS

There were 7590 participants who experienced hospitalisation with injecting-related bacterial infections (35% female; median age 38 years; 78% hospitalised with skin and soft-tissue infections). Risk for injecting-related bacterial infections was elevated for two weeks following release from prison (aIRR 1.45; 95%CI 1.22-1.72). Risk was increased during two weeks before (aIRR 1.89; 95%CI 1.59-2.25) and after (aIRR 1.91; 95%CI 1.54-2.36) discontinuation of OAT, and during two weeks before (aIRR 3.63; 95%CI 3.13-4.22) and after (aIRR 2.52; 95%CI 2.09-3.04) OAT initiation.

CONCLUSION

Risk of injecting-related bacterial infections varies greatly within-individuals over time. Risk is raised immediately after prison release, and around initiation and discontinuation of OAT. Social contextual factors likely contribute to excess risks at transitions in incarceration and OAT exposure.

[Unsafe practices fostering cutaneous abscesses in people who inject substances : Results from the ANRS-OUTSIDER study]

INTRODUCTION

Cutaneous abscesses are a common complication of intravenous substance use. Although these skin and soft tissue infections represent one of the main causes of emergency room visits and hospitalizations in people who inject drugs (PWID), data on their prevalence and causes are scarce. The present study was part of the larger ANRS-OUTSIDER project and aimed to study the factors associated with skin abscesses in PWID, focusing in particular on the different stages of injection.

METHOD

Analyses were based on data of the 164 persons who regularly injected psychoactive substances participating in the French ANRS-OUTSIDER project. A face-to-face questionnaire collected data on sociodemographics, substance use, injection practices, and experience of skin abscesses in the previous six months. Factors associated with skin abscesses were studied using a logistic regression model.

RESULTS

Of the 140 participants for whom abscess data were recorded at inclusion, 35% reported having a skin abscess in the previous six months. Factors associated with skin abscesses were: benefiting from universal health coverage (PUMA/CMU/AME) (Odd ratio (OR) = 0.28, confidence interval (CI) à 95%=0.08-0.99), finding the vein to inject by touch (OR=3.44, 95% CI=1.41-8.43) and licking the needle before injection (OR=5.16, 95% CI=1.10-24.30).

CONCLUSION

Our results highlight that skin abscesses were very frequent among the complications observed in our sample of French PWID, and that certain injection practices fostered their occurrence. These data will provide stakeholders with useful information to improve prevention and harm reduction messages for PWID.

Development, acceptability and feasibility of a personalised, behavioural intervention to prevent bacterial skin and soft tissue infections among people who inject drugs: a mixed-methods Person-Based Approach study

BACKGROUND

Skin and soft tissue infections (SSTI) among people who inject drugs (PWID) are a public health concern. This study aimed to co-produce and assess the acceptability and feasibility of a behavioural intervention to prevent SSTI.

METHODS

The Person-Based Approach (PBA) was followed which involves: (i) collating and analysing evidence; (ii) developing guiding principles; (iii) a behavioural analysis; (iv) logic model development; and (v) designing and refining intervention materials. Co-production activities with target group representatives and key collaborators obtained feedback on the intervention which was used to refine its design and content. The intervention, harm reduction advice cards to support conversation between service provider and PWID and resources to support safer injecting practice, was piloted with 13 PWID by four service providers in Bristol and evaluated using a mixed-methods approach. Semi-structured interviews were conducted with 11 PWID and four service providers. Questionnaires completed by all PWID recorded demographic characteristics, SSTI, drug use and treatment history. Interviews were analysed thematically and questionnaires were analysed descriptively.

RESULTS

Published literature highlighted structural barriers to safer injecting practices, such as access to hygienic injecting environments and injecting practices associated with SSTI included: limited handwashing/injection-site swabbing and use of too much acidifier to dissolve drugs. Co-production activities and the literature indicated vein care and minimisation of pain as PWID priorities. The importance of service provider-client relationships and non-stigmatising delivery was highlighted through the co-production work. Providing practical resources was identified as important to address environmental constraints to safer injecting practices. Most participants receiving the intervention were White British, male, had a history of SSTI and on average were 43.6 years old and had injected for 22.7 years. The intervention was well-received by PWID and service providers. Intervention content and materials given out to support harm reduction were viewed positively. The intervention appeared to support reflections on and intentions to change injecting behaviours, though barriers to safer injecting practice remained prominent.

CONCLUSIONS

The PBA ensured the intervention aligned to the priorities of PWID. It was viewed as acceptable and mostly feasible to PWID and service providers and has transferability promise. Further implementation alongside broader harm reduction interventions is needed.

Hormone Replacement Therapy Does Not Eliminate Risk Factors for Joint Complications following Total Joint Arthroplasty: A Matched Cohort Study

Aging causes a reduction in testosterone and estrogen, which is linked to diminished bone mineral density. Hormone replacement therapy and its effect on the outcome of joint arthroplasties is unclear. The purpose of this study was to analyze the impact of testosterone replacement therapy (TRT) and estrogen replacement therapy (ERT) on the medical and joint outcomes of total hip (THA) and total knee arthroplasties (TKA). A retrospective cohort study was conducted using the PearlDiver database. Patients who received TRT or ERT perioperatively were matched to controls. Rates of 90-day medical complications and 2-year joint complications were queried. Patients who received TRT had an increased risk of revision, periprosthetic joint infection, and pooled joint complications within 2 years following a THA and increased rates of septic and aseptic revisions, and aseptic loosening after TKA compared to the control cohort. Patients receiving ERT had increased rates of aseptic loosening and pooled joint complications within 2 years following THA and increased rates of all-cause revisions and pooled joint complications after TKA. Patients who received TRT demonstrated significantly higher rates of revision rates and PJI. Patients who received perioperative ERT were significantly more likely to have increased risks of revision rates and joint infections.

The impact of opioid agonist treatment on hospitalisations for injecting-related diseases among an opioid dependent population: A retrospective data linkage study

BACKGROUND

Injecting-related bacterial and fungal infections cause substantial illness and disability among people who use illicit drugs. Opioid agonist treatment (OAT) reduces injecting frequency and the transmission of blood borne viruses. We estimated the impact of OAT on hospitalisations for non-viral infections and examine trends in incidence over time.

METHODS

We conducted a retrospective cohort study using linked administrative data. The cohort included 47 163 individuals starting OAT between August 2001 and December 2017 in New South Wales, Australia, with 454 951 person-years of follow-up. The primary outcome was hospitalisation for an injecting-related disease. The primary exposure was OAT status (out of OAT, first four weeks of OAT, and OAT retention [i.e., more than four weeks in treatment]). Covariates included demographic characteristics, year of hospitalisation, and recent clinical treatment.

RESULTS

9122 participants (19.3%) had at least one hospitalisation for any injecting-related disease. Compared to time out of treatment, retention on OAT was associated with a reduced rate of injecting-related diseases (adjusted rate ratio[ARR]=0.92; 95%CI 0.87-0.97). The first four weeks of treatment was associated with an increased rate (ARR 1.53, 95%CI 1.38-1.70), which we believe is explained by referral pathways between hospital and community OAT services. The age-adjusted incidence rates of hospitalisations for any injecting-related disease increased from 34.8 (95% CI =30.2-40.0) per 1000 person-years in 2001 to 54.9 (95%CI=51.3-58.8) in 2017.

INTERPRETATION

Stable OAT is associated with reduced hospitalisations for injecting-related bacterial infections; however, OAT appears insufficient to prevent these harms as the rate of these infections is increasing in Australia.

Self and professional treatment of skin and soft tissue infections among women who inject drugs: Implications for wound care provision to prevent endocarditis

Background:

Skin and soft tissue infections (SSTI) are common among people who inject drugs and can result in severe health consequences, including infective endocarditis. Numerous barriers to accessing care often prevent people who inject drugs from seeking healthcare including past negative healthcare experiences, transportation, and shame around drug use. These barriers can lead some people who inject drugs to self-care instead of seeking formal treatment.

Methods:

We explored the prevalence of SSTIs and associated treatment behaviors among women who inject drugs and sell sex (N = 114). Women reported their drug use and SSTI histories. Those who experienced an SSTI reported if they self-treated their SSTIs and/or sought formal treatment.

Results:

Half (50.0%) experienced at least one SSTI in the past 6 months. SSTIs were more common among those who injected painkillers (24.6% vs 8.8%, p = 0.02) and who had ever been treated for endocarditis (28.1% vs 10.5%, p = 0.02). SSTIs were less common among those who injected multiple times per day (17.9% vs 38.6%, p = 0.01) and always injected with a sterile syringe (19.3% vs 42.1%, p = 0.01). Among those who experienced an SSTI, most (85.7%) reported self-treating, and half (52.6%) sought formal care. The emergency room was the most common source of care (73.3%).

Conclusions:

When experiencing SSTIs, women often opted to self-treat rather than seek formal healthcare. A lack of formal care can lead to infections progressing to serious conditions, like endocarditis. Self-treatment with non-prescribed antibiotics may further result in antibiotic-resistant infections. Low threshold, stigma free, community-based wound care programs are warranted.

Severe bacterial infections in people who inject drugs: the role of injection-related tissue damage

Background

In the context of the current U.S. injection drug use epidemic, targeted public health harm reduction strategies have traditionally focused on overdose prevention and reducing transmission of blood-borne viral infections. Severe bacterial infections (SBI) associated with intravenous drug use have been increasing in frequency in the U.S. over the last decade. This qualitative study aims to identify the risk factors associated with SBI in hospitalized individuals with recent injection drug use.

Methods

Qualitative analysis (n = 15) was performed using an in-depth, semi-structured interview of participants admitted to Bellevue Hospital, NYC, with SBI and recent history of injection drug use. Participants were identified through a referral from either the Infectious Diseases or Addition Medicine consultative services. Interviews were transcribed, descriptively coded, and analyzed for key themes.

Results

Participants reported a basic understanding of prevention of blood-borne viral transmission but limited understanding of SBI risk. Participants described engagement in high risk injection behaviors prior to hospitalization with SBI. These practices included polysubstance use, repetitive tissue damage, nonsterile drug diluting water and multipurpose use of water container, lack of hand and skin hygiene, re-use of injection equipment, network sharing, and structural factors leading to an unstable drug injection environment. Qualitative analysis led to the proposal of an Ecosocial understanding of SBI risk, detailing the multi-level interplay between individuals and their social and physical environments in producing risk for negative health outcomes.

Conclusions

Structural factors and injection drug use networks directly impact drug use, injection drug use practices, and harm reduction knowledge, ultimately resulting in tissue damage and inoculation of bacteria into the host and subsequent development of SBI. Effective healthcare and community prevention efforts targeted toward reducing risk of bacterial infections could prevent long-term hospitalizations, decrease health care expenditures, and reduce morbidity and mortality.

Immediate Interventions After Surgery to Reduce Readmission for Upper Extremity Infections

ABSTRACT

Upper extremity infections (UEIs), commonly caused by intravenous drug use and direct trauma to the hand, can be devastating. Many studies support hand therapy postoperatively to improve outcomes. This population of patients often experience increased returns to the emergency department (ED) for treatment, repeat surgery, poor function, and increased hospital expenditure.This is a 2-phase study to investigate and intervene on the care pathway for patients undergoing surgery for UEI at a single urban university hospital. For the first 6-month phase, all patients with UEI requiring surgery received the standard of care, including written discharge instructions, a scheduled follow-up, and a determination for hand therapy based on evaluation. During the second phase, over the following 6 months, all patients with UEI requiring surgery received an intervention before discharge, in addition to standard of care, including a scripted educational session on the importance of hand therapy by a resident physician, home exercise program instructions, and a referral to hand therapy before discharge. Outcome measures were assessed for 6 months. Outcome measures included follow-up, hand therapy attendance, ED visits for the same complaint, readmissions, and reoperations.Forty-seven patients were in the first control group without intervention and 41 patients were in the second intervention group. Of the control group, 43% attended a follow-up appointment, 2% attended hand therapy, and 45% presented to the ED, resulting in a total of 167 visits. Eleven presented to the ED and were readmitted for complications from surgery, all 11 required a second operation. In the intervention group, 54% attended a follow-up appointment (P = 0.044), more patients attended hand therapy (22% P = 0.013), and 24% presented to the ED (P = 0.047), resulting in 40 ED visits.Seven were readmitted for complications from surgery and 4 required a second operation (P = 0.1). Early, simple intervention and education prove to be an effective method to decrease emergency department burden and healthcare expenditure for treatment of a challenging population. Although additional education and referral to hand therapy utilization do not change operation rates, it decreased returns to the ED, readmissions, and increased follow-up.

Methods and indicators to validate country reductions in incidence of hepatitis C virus infection to elimination levels set by WHO

One of the main goals of the 2016 Global Health Sector Strategy on viral hepatitis is the elimination of hepatitis C virus (HCV) as a public health problem by 2030, defined as an 80% reduction in incidence and 65% reduction in mortality relative to 2015. Although monitoring HCV incidence is key to validating HCV elimination, use of the gold-standard method, which involves prospective HCV retesting of people at risk, can be prohibitively resource-intensive. Additionally, few countries collected quality data in 2015 to enable an 80% decrease by 2030 to be calculated. Here, we first review different methods of monitoring HCV incidence and discuss their resource implications and applicability to various populations. Second, using mathematical models developed for various global settings, we assess whether trends in HCV chronic prevalence or HCV antibody prevalence or scale-up levels for HCV testing, treatment, and preventative interventions can be used as reliable alternative indicators to validate the HCV incidence target. Third, we discuss the advantages and disadvantages of an absolute HCV incidence target and suggest a suitable threshold. Finally, we propose three options that countries can use to validate the HCV incidence target, depending on the available surveillance infrastructure.

Under the Skin: The Relationship Between Subcutaneous Injection and Skin Infections Among People Who Inject Drugs

OBJECTIVES

People who inject drugs (PWID) are at increased risk for numerous negative health outcomes. Subcutaneous injections (aka skin popping) can result in greater risk of skin and soft tissue infections (SSTIs), but less is known about PWID who choose this route of administration. This study compares subcutaneous injectors to intravenous injectors, characterizes those who inject subcutaneously, and examines whether subcutaneous injection is associated with SSTIs in the past year.

METHODS

A cohort of hospitalized PWID (n = 252) were interviewed regarding injection-related behaviors, history of SSTI, and knowledge of subcutaneous injection risk. We examined differences between those who do and do not inject subcutaneously and used a negative binomial regression model to estimate adjusted odds associating subcutaneous injection and SSTI.

RESULTS

Participants averaged 38 years, with 58.3% male, 59.5% White, 20.6% Black, and 15.9% Latinx. PWID who performed subcutaneous injection were not demographically different from other PWID; however, the mean rate of past year SSTIs was higher for persons injecting subcutaneously than for those who did not (1.98 vs 0.96, P < 0.001). Persons injecting subcutaneously did not differ from those who injected intravenously in terms of their knowledge of subcutaneous injection risk (P = 0.112) and knowledge score was not associated with SSTIs (P = 0.457).

CONCLUSIONS

PWID who perform subcutaneous injections are demographically similar to other PWID but had higher rates of past year SSTIs. Knowledge of subcutaneous injection risk was not associated with SSTI risk.

Association of skin infections with sharing of injection drug preparation equipment among people who inject drugs

BACKGROUND

Sharing needles and injection drug preparation equipment (IDPE) among people who inject drugs (PWID) are well-established risk factors for viral transmission. Shared needles and IDPE may serve as bacterial niduses for skin and soft tissue infections (SSTI). Given the rising rates of SSTI in PWID, we investigated the association of needle and IDPE sharing on incidence of SSTI in a cohort of PWID.

METHODS

Inpatient PWID (N = 252) were recruited to a randomized controlled trial of an intervention aimed at reducing infections. The primary outcome was self-reported incidence of SSTI one-year post-hospitalization. In this secondary analysis, we assessed two variables: 1) sharing of IDPE alone, 2) sharing needles with or without IDPE, and compared these groups separately to persons who reported no sharing of needles or IDPE via a mixed-effects negative binomial regression model to estimate the effect of baseline sharing behavior on SSTI during follow-up via incidence rate ratios (IRR).

RESULTS

Participant characteristics: 38 years [mean], 58% male, 60% White, 90% primarily injected opioids, 1.58 (± 2.35) mean SSTI in the year prior to baseline. In terms of sharing behavior, 29% didn't share needles or IDPE, 13% shared IDPE only, and 58% shared needles with or without IDPE three months prior to baseline. After adjusting for co-variables, PWID who shared IDPE alone had a 2.2 fold higher IRR of SSTI (95%CI 1.27; 3.85, p = 0.005) and PWID who shared needles with or without IDPE had a 3.31 fold higher IRR of SSTI (95%CI 2.04; 5.37, p < 0.001), compared to those who did not share any equipment. The number of SSTI at baseline was associated with an IRR of 1.20 of SSTI during follow-up (95%CI 1.09; 1.32, p < 0.001).

CONCLUSIONS

In this cohort of hospitalized PWID, we found a significant association between baseline sharing of IDPE alone and of sharing of needles with or without IDPE with one-year incidence of SSTI.

Injecting drug use, the skin and vasculature

Damage to the skin, subcutaneous tissues and blood vessels are among the most common health harms related to injecting drug use. From a limited range of early reports of injecting-related skin and soft tissue damage there is now an increasing literature relating to new drugs, new contaminants and problems associated with unsafe injection practices. Clinical issues range from ubiquitous problems associated with repeated minor localised injection trauma to skin and soft tissue and infections around injection sites, to systemic blood infections and chronic vascular disease. The interplay of limited availability and access to sterile injecting equipment, poor injecting technique, compromised drug purity, drug toxicity and difficult personal and environmental conditions give rise to injection-related health harms. This review of injecting-related skin, soft tissue and vascular damage focuses on epidemiology and causation, clinical examination and investigation, treatment and prevention.

Recurring Severe Injection-Related Infections in People Who Inject Drugs and the Need for Safe Injection Sites in Madrid, Spain

BACKGROUND

An estimated 58 749 people with opioid use disorder engaged in opioid agonist therapy (OAT) in 1132 centers in Spain during 2017. We aimed to calculate the incidence of severe injection-related infections in people who inject drugs (PWID) engaged in OAT in harm reduction settings without a safe consumption space.

METHODS

A retrospective cohort study was performed in PWID engaged in OAT and in a mobile harm reduction unit to quantify admissions to a referral hospital for any severe injection-related infections between 1 January 2016 and 31 December 2019. A Cox proportional hazard regression analysis was used to assess factors associated with any severe injection-related infection.

RESULTS

Two hundred thirty-seven PWID who engaged in OAT were included in the study. After a median follow-up of 5.5 months (interquartile range [IQR], 1.3-22.7 months), a total of 104 episodes of severe injection-related infections occurred among 56 individuals, and admission due to a second event occurred in 35.7% of this same group. The incidence density of any type of severe injection-related infection was 26.8 (95% confidence interval [CI], 20.2-34.8) episodes per 100 person-years, and the incidence density of complicated skin and soft tissue infections that required hospital admission was 20.4 (95% CI, 15.0-27.3) episodes per 100 person-years. Fifty-six (53.8%) of all the episodes were patient-directed discharge (PDD), and people who had 2 or more hospital admissions had a higher PDD frequency.

CONCLUSIONS

Severe injection-related infections remain highly prevalent among PWID cared for in a harm reduction setting without a safe consumption space. PDD was more frequent among higher-risk individuals who presented 2 or more hospital readmissions.

The wound that closes doors: Lived experiences and complexities of injection-related injuries and infections among people who inject drugs through an ethnographic lens

BACKGROUND

Besides HIV, people who inject drugs (PWID) experience other biomedical adversities, including injection-related injuries and infections. Yet, they are often inadequately addressed due to the prioritisation of HIV-related issues. This article explored the risk environment and socio-structural adversities of PWID living with injection-related injuries and infections, as well as existing management and treatment challenges of these conditions in harm reduction interventions.

METHODS

We undertook an ethnographic study from April 2018 to December 2019 in selected areas of Dhaka, Bangladesh. This component of the study involved 2500 hours of observations and informal conversations, 35 in-depth interviews and five focus group discussions with PWID experiencing injection-related injuries and infections. We also performed seven key-informant interviews with service providers and clinical experts. We applied thematic analysis and used various theoretical social scientific conceptualisations to analyse the relationship between the biomedical realities and socio-structural vulnerabilities of PWID.

RESULTS

Our findings indicated that PWID's physical, legal and socio-economic environments predisposed PWID to risky practices which ultimately precipitated injection-related injuries and infections. These injection-related injuries and infections consequently displaced them in spheres of social exclusion, stigmatisation, physical pain and disability and, hence, fueled their feelings of distress and despondence. Our findings also presented limitations in the management strategy of these injection-related injuries and infections. Specifically, service providers misconstrued all these complexities as "abscesses", thus applying a simplistic "one-size-fits-all" approach without accounting for the diversity of these complexities. This led to a paucity of tailored care and management approaches which could precipitate unfavourable treatment outcomes, such as chronic and complicated cases with antibiotic resistance.

CONCLUSION

Injection-related injuries and infections nestled PWID within various prongs of biomedical and socio-structural adversity, without viable and targeted treatment modalities. Thus, it is integral to nurture a multifaceted harm reduction intervention tailored to their biomedical and socio-structural needs.

Soft Tissue, Bone, and Joint Infections in People Who Inject Drugs

Infections are a common complication among people who inject drugs (PWID). Skin and soft tissue infections (SSTI) as well as bone and joint infections comprise a significant source of morbidity and mortality among this population. The appropriate recognition and management of these infections are critical for providers, as is familiarity with harm-reduction strategies. This review provides an overview of the presentation and management of SSTI and bone and joint infections among PWID, as well as key prevention measures that providers can take.

Hospital Costs of Injection Drug Use in Florida

People who inject drugs (PWID) experience significant injection-related infections (IRIs) at significant healthcare system cost. This study used and validated an algorithm based on the International Classification of Diseases, Tenth Revision, to estimate hospitalized PWID populations, assess the total statewide morbidity for IRIs among PWID, and calculate associated costs of care.

Socioeconomic stability is associated with lower injection frequency among people with distinct trajectories of injection drug use

BACKGROUND

Little is known about how socioeconomic circumstances relate to injection frequencies among people who inject drugs (PWID) with diverse trajectories of injection. We aimed to characterize trajectories of injection drug use in a community-based sample of PWID over 7.5 years and to investigate the extent to which two modifiable factors reflecting socioeconomic stability-stable housing and stable income-relate to injection frequencies across distinct trajectories.

METHODS

HEPCO is an open, prospective cohort study of PWID living in Montréal with repeated follow-up at three-month or one-year intervals. Self-reported data on injection frequency, housing and income are collected at each visit. Injection frequency was defined as the number of injection days (0-30), reported for each of the past three months. Using group-based trajectory modeling, we first estimated average trajectories of injection frequency. Then, we estimated the trajectory group-specific average shift upward or downward associated with periods of stable housing and stable income relative to periods when these conditions were unstable.

RESULTS

Based on 19,527 injection frequency observations accrued by 529 participants followed over 2011-2019 (18.3% female, median age: 41), we identified five trajectories of injection frequency: three characterized by sustained injection at different frequencies (28% infrequent; 19% fluctuating; 19% frequent), one by a gradual decline (12%), and another by cessation (28%). Periods of stable housing and stable income were each independently associated with a lower injection frequency, on average, in all five trajectory groups (2.2-7.5 fewer injection days/month, depending on the factor and trajectory group).

CONCLUSION

Trajectories of injection drug use frequency were diverse and long-lasting for many PWID. Despite this diversity, socioeconomic stability was consistently associated with a lower injection frequency, emphasizing the close relationship between access to fundamental necessities and injection patterns in all PWID, irrespective of whether they are on a path to cessation or sustained injecting.

A randomized controlled trial of a brief behavioral intervention to reduce skin and soft tissue infections among people who inject drugs

BACKGROUND

People who inject drugs (PWID) are at high risk for skin and soft tissue infections (SSTIs), but few interventions have targeted their reduction. The goal of the current study was to test the effects of a brief skin and needle hygiene behavioral intervention (SKIN) in a two-group randomized controlled trial with 12-month follow-up.

METHOD

PWID (N = 252) were recruited from inpatient hospital units at a single urban medical center site and randomly assigned to an assessment-only (AO) condition or SKIN, which was a two-session intervention that included psychoeducation, behavioral skills demonstrations, and motivational interviewing. Mixed effects generalized linear models assessed the impact of the intervention on frequency of: 1) self-reported SSTIs, 2) uncleaned skin injections, and 3) injection.

RESULTS

Participants were 58.3 % male, 59.5 % White, and averaged 38 years of age. SKIN participants had 35 % fewer SSTIs compared to AO (p = .179), a difference of nearly one infection per year. The mean rate of uncleaned skin injections was about 66 % lower (IRR = 0.34, 95 % CI 0.20; 0.59, p < .001) among SKIN participants compared to AO. Almost one-third of participants reported no injection over follow-up and the mean rate of injection during follow-up was about 39 % lower (IRR = 0.61; 95 % CI 0.36; 1.02, p = .058) among persons randomized to SKIN than AO.

CONCLUSIONS

The SKIN intervention reduced uncleaned skin injections but did not reduce SSTIs significantly more than a control condition. Brief interventions can improve high-risk practices among PWID and lead to clinically meaningful outcomes.

Predictors of skin and soft tissue infections among sample of rural residents who inject drugs

Introduction

Skin and soft tissue infections (SSTIs) are among the leading causes of morbidity and mortality for people who inject drugs (PWID). Studies demonstrate that certain injection practices correlate with SSTI incidence among PWID. The opioid epidemic in the USA has particularly affected rural communities, where access to prevention and treatment presents unique challenges. This study aims to estimate unsafe injection practices among rural-dwelling PWID; assess treatments utilized for injection related SSTIs; and gather data to help reduce the overall risk of injection-related SSTIs.

Methods

Thirteen questions specific to SSTIs and injection practices were added to a larger study assessing unmet health care needs among PWID and were administered at six syringe exchange programs in rural Wisconsin between May and July 2019. SSTI history prevalence was estimated based on infections reported within one-year prior of response and was compared to self-reported demographics and injection practices.

Results

Eighty responses were collected and analyzed. Respondents were white (77.5%), males (60%), between the ages 30 and 39 (42.5%), and have a high school diploma or GED (38.75%). The majority of respondents (77.5%) reported no history of SSTI within the year prior to survey response. Females were over three times more likely to report SSTI history (OR = 3.07, p = 0.038) compared to males. Water sources for drug dilution (p = 0.093) and frequency of injecting on first attempt (p = 0.037), but not proper skin cleaning method (p = 0.378), were significantly associated with a history of SSTI. Injecting into skin (p = 0.038) or muscle (p = 0.001) was significantly associated with a history of SSTI. Injection into veins was not significantly associated with SSTI (p = 0.333).

Conclusion

Higher-risk injection practices were common among participants reporting a history of SSTIs in this rural sample. Studies exploring socio-demographic factors influencing risky injection practices and general barriers to safer injection practices to prevent SSTIs are warranted. Dissemination of education materials targeting SSTI prevention and intervention among PWID not in treatment is warranted.

Opioid Use Disorder and Associated Infectious Disease: The Role of the Laboratory in Addressing Health Disparities

BACKGROUND

Opioid use disorder, defined as a pattern of problematic opioid use leading to clinically significant impairment, has resulted in considerable morbidity and mortality throughout the world. This is due, at least in part, to the marginalized status of patients with opioid use disorder, limiting their access to appropriate laboratory testing, diagnosis, and treatment. Infections have long been associated with illicit drug use and contribute considerably to morbidity and mortality. However, barriers to testing and negative stigmas associated with opioid use disorder present unique challenges to infectious disease testing in this patient population.

CONTENT

This review addresses the associations between opioid use disorder and infectious organisms, highlighting the health disparities encountered by patients with opioid use disorder, and the important role of laboratory testing for diagnosing and managing these patients.

SUMMARY

Infections are among the most frequent and adverse complications among patients with opioid use disorder. As a result of health disparities and systemic biases, patients that misuse opioids are less likely to receive laboratory testing and treatment. However, laboratories play a crucial in identifying patients that use drugs illicitly and infections associated with illicit drug use.

Long-term infective endocarditis mortality associated with injection opioid use in the United States: a modeling study

BACKGROUND

The expansion of the U.S. opioid epidemic has led to significant increases in infections such as infective endocarditis (IE), which is tied to injection behaviors. We aimed to estimate the population-level IE mortality among people who inject opioids and compare the risk of IE death against the risks of death from other causes.

METHODS

We developed a microsimulation model of the natural history of injection opioid use. We defined injection behavior profile by both injection frequency and injection techniques. We accounted for competing risks of death and populated the model with primary and published data. We modeled cohorts of 1 million individuals with different injection behavior profiles until age 60. We combined model-generated estimates with published data to project the total expected IE deaths in the U.S. by 2030.

RESULTS

The probability of death from IE by age 60 years for 20-, 30-, and 40-year-old men with high frequency use with higher infection risk techniques compared to lower risk techniques for IE was 53.8% versus 3.7%, 51.4% versus 3.1%, and 44.5% versus 2.2%, respectively. The predicted population-level attributable fraction of 10-year mortality for IE among all risk groups was 20%. We estimated that approximately 257,800 people are expected to die from IE by 2030.

CONCLUSIONS

The expected burden of IE among people who inject opioids in the U.S. is large. Adopting a harm reduction approach, including expansion of syringe service programs, to address injection behaviors could have a major impact on decreasing the mortality associated with the opioid epidemic.

Clonal expansion of community-associated meticillin-resistant Staphylococcus aureus (MRSA) in people who inject drugs (PWID): prevalence, risk factors and molecular epidemiology, Bristol, United Kingdom, 2012 to 2017

Background: In 2015, Bristol (South West England) experienced a large increase in cases of meticillin-resistant Staphylococcus aureus (MRSA) infection in people who inject drugs (PWID).

Aim: We aimed to characterise and estimate the prevalence of MRSA colonisation among PWID in Bristol and test evidence of a clonal outbreak.

Methods: PWID recruited through an unlinked-anonymous community survey during 2016 completed behavioural questionnaires and were screened for MRSA. Univariable logistic regression examined associations with MRSA colonisation. Whole-genome sequencing used lineage-matched MRSA isolates, comparing PWID (screening and retrospective bacteraemia samples from 2012-2017) with non-PWID (Bristol screening) in Bristol and national reference laboratory database samples.

Results: The MRSA colonisation prevalence was 8.7% (13/149) and was associated with frequently injecting in public places (odds ratio (OR): 5.5; 95% confidence interval (CI):1.34–22.70), recent healthcare contact (OR: 4.3; 95% CI: 1.34–13.80) and injecting in groups of three or more (OR: 15.8; 95% CI: 2.51–99.28). People reporting any one of: injecting in public places, injection site skin and soft tissue infection or hospital contact accounted for 12/13 MRSA positive cases (sensitivity 92.3%; specificity 51.5%). Phylogenetic analysis identified a dominant clade associated with infection and colonisation among PWID in Bristol belonging to ST5-SCCmecIVg.

Conclusions: MRSA colonisation in Bristol PWID is substantially elevated compared with general population estimates and there is evidence of clonal expansion, community-based transmission and increased infection risk related to the colonising strain. Targeted interventions, including community screening and suppression therapy, education and basic infection control are needed to reduce MRSA infections in PWID.

Incidence and treatment costs of severe bacterial infections among people who inject heroin: A cohort study in South London, England

BACKGROUND

People who inject drugs often get bacterial infections. Few longitudinal studies have reported the incidence and treatment costs of these infections.

METHODS

For a cohort of 2335 people who inject heroin entering treatment for drug dependence between 2006 and 2017 in London, England, we reported the rates of hospitalisation or death with primary causes of cutaneous abscess, cellulitis, phlebitis, septicaemia, osteomyelitis, septic arthritis, endocarditis, or necrotising fasciitis. We compared these rates to the general population. We also used NHS reference costs to calculate the cost of admissions.

RESULTS

During a median of 8.0 years of follow-up, 24 % of patients (570/2335) had a severe bacterial infection, most commonly presenting with cutaneous abscesses or cellulitis. Bacterial infections accounted for 13 % of all hospital admissions. The rate was 73 per 1000 person-years (95 % CI 69-77); 50 times the general population, and the rate remained high throughout follow-up. The rate of severe bacterial infections for women was 1.50 (95 % CI 1.32-1.69) times the rate for men. The mean cost per admission was £4980, and we estimate that the annual cost of hospital treatment for people who inject heroin in London is £4.5 million.

CONCLUSIONS

People who inject heroin have extreme and long-term risk of severe bacterial infections.

Association of Self-Reported Abscess With High-Risk Injection-Related Behaviors Among Young Persons Who Inject Drugs

Abscess is a common source of morbidity for people who inject drugs. We used data from the Study to Assess Hepatitis C Risk to measure prevalence of abscess and identify factors associated with the history of abscess. Of 541 participants, 388 (72%) were male and 149 (28%) were female. Almost half (n = 258, 48%) reported ever having an abscess. Persons who inject drugs with an abscess history were significantly more likely to have more injection partners (p = .01), inject heroin daily (p < .05), and share cookers (p = .001) and less likely to report using new syringes with each injection (p = .02). Most reported self-treating their last abscess and increasing drug use when having an abscess. High-risk injection-related activity was associated not only with infections such as HIV and hepatitis C virus but also with abscess. Nurses should screen patients presenting with abscess for high-risk practices and provide prevention education.

Factors associated with skin and soft tissue infections among people who inject drugs in the United Kingdom: A comparative examination of data from two surveys

BACKGROUND

People who inject drugs (PWID) are at high risk of injection-related skin and soft tissue infections (SSTI). If not treated promptly, these can lead to serious health complications, which are a considerable healthcare burden. Data from two community surveys, with different approaches, were used to assess SSTI prevalence and associated factors among PWID to inform intervention implementation.

METHODS

Data were analysed from two surveys, a national surveillance survey (n=2,874; 2017-18) of infections among PWID in the United Kingdom (UK) and an in-depth survey (n=455; 2018-19) of SSTI among PWID based in London, UK. Multivariable logistic regression models were constructed to ascertain the factors associated with self-reported SSTI.

RESULTS

High prevalence of SSTI were reported in both samples: 52 % of participants from the national surveillance survey reported having SSTI within the preceding 12 months and 65 % of the London sample reported a lifetime history of SSTI. The factors associated with SSTI in both surveys were similar, including older age; number of years injecting; number of attempts required to inject into the vein; injecting into the hands, feet, groin or neck and re-using or sharing needles/syringes.

CONCLUSIONS

The number of PWID reporting SSTI in the UK is concerningly high. The two surveys used different recruitment approaches but found similar associations. We provide strong evidence of a relationship between venous access difficulty and SSTI. To stem the increase of SSTI and related complications in the UK, it is crucial that interventions attend to the underlying causes of venous damage among PWID.

Self-treatment of skin infections by people who inject drugs

BACKGROUND AND AIMS

Persons who inject drugs (PWID) experience high rates of skin and soft tissue infections (SSTI) and often access emergency or inpatient treatment. However, many PWID do not seek care and self-treat some or all of their infections. The goal of the current study was to examine predictors of self-treatment of SSTI in a sample of hospitalized PWID, and describe methods of and reasons for self-treatment.

METHODS

PWID (N = 252) were recruited from inpatient medical units at an urban safety-net hospital to join a behavioral intervention trial. The baseline interview focused on past-year SSTI incidence and related treatment, including reasons for not accessing medical care and methods of self-treatment.

RESULTS

Of study participants, 162 (64%) reported having at least one SSTI in the past year. This subset was 59.9% White/Caucasian with a mean age of 38.0 (SD + 10.5). One-third of these participants (32.3%) reported ever self-treating SSTI in the past year. In a logistic regression model, number of past-year infections (OR = 1.81, p < .001) and positive outlook (OR = 2.46, p < .001) were associated with self-treatment of SSTI. Common methods of self-treatment included mechanically draining sores, applying heat/warm compress, and cleaning affected areas. Continued drug use and belief that infections were not serious and could be self-treated were two main reasons for not seeking professional medical care.

CONCLUSIONS

Interventions targeting SSTI among PWID should include education on when to seek medical care and the risks of serious infection, and could be implemented at local clinics or harm reduction programs to increase access.

Use of alcohol swabs to clean injecting sites among people who regularly inject drugs in Australia

INTRODUCTION AND AIMS

Cleaning drug injection sites with alcohol swabs prior to injecting reduces risk of abscesses and other skin and soft tissue infections (SSTI). Better understanding of swabbing behaviours can inform interventions to improve injecting hygiene. We aimed to determine the socio-demographic, drug use and injecting risk exposure correlates of swabbing prior to injecting and reasons for not swabbing.

DESIGN AND METHODS

The Illicit Drug Reporting System recruited participants who had injected drugs at least monthly in the past six months in June-July 2017 from all Australian capital cities via needle and syringe programs and word-of-mouth. A structured interview was used to collect information on drug use and related behaviour, as well as swabbing practices. Logistic regression was used to identify factors associated with not swabbing at last injection.

RESULTS

Of 853 respondents, one-quarter (26%) reported that they did not swab prior to their last injection. In adjusted analyses, crystal methamphetamine as the last drug injected, past month receptive or distributive syringe sharing, and past month re-use of one's own needle were significantly associated with not swabbing at last injection. Among participants who did not swab at last injection, swabbing was frequently considered unnecessary and a small number disliked using alcohol swabs.

DISCUSSION AND CONCLUSIONS

Efforts are needed to increase awareness of the importance of injecting hygiene in preventing SSTI. Interventions to increase swabbing should be included as part of a wider package of injecting hygiene education, particularly in light of associations with receptive and/or distributive syringe sharing.

Injecting-related health harms and overuse of acidifiers among people who inject heroin and crack cocaine in London: a mixed-methods study

Background

Venous access is a priority for people who inject drugs (PWID). Damage and scarring of peripheral veins can exacerbate health harms, such as skin and soft tissue infections (SSTI), and promote transitions to femoral and subcutaneous injecting. Brown heroin available in Europe requires acidification for injection preparation. In this paper, we present mixed-methods data to explore our hypothesis of a link between overly acidic injection solutions, venous damage and SSTI risk.

Methods

We present a structured survey (n = 455) and in-depth qualitative interview (n = 31) data generated with PWID in London for the Care & Prevent study. Participants provided life history data and detail on injecting environments and drug preparation practices, including the use of acidifiers. Bivariate and multivariate analyses were conducted using a logistic regression for binary outcomes to explore associations between outcomes and excessive acidifier use. Grounded theory principles informed inductive qualitative analysis. Mixed-methods triangulation was iterative with results comparison informing the direction and questions asked of further analyses.

Results

Of the 455 participants, most (92%) injected heroin and/or crack cocaine, with 84% using citric as their primary acid for drug preparation. Overuse of acidifier was common: of the 418 who provided an estimate, 36% (n = 150) used more than ½ a sachet, with 30% (n = 127) using a whole sachet or more. We found associations between acidifier overuse, femoral injecting and DVT, but not SSTI. Qualitative accounts highlight the role of poor heroin quality, crack cocaine use, information and manufacturing constraints in acidifier overuse. Painful injections and damage to peripheral veins were common and often attributed to the use of citric acid.

Conclusions

To reduce injecting-related injury and associated consequences, it is crucial to understand the interplay of environmental and practice-based risks underpinning venous damage among PWID. Overuse of acidifier is a modifiable risk factor. In the absence of structural supports such as safe injecting facilities or the prescribing of pharmaceutical diamorphine, there is an urgent need to revisit injecting paraphernalia design and distribution in order to alleviate health harms and distress among the most marginalised.

Reducing injection intensity is associated with decreased risk for invasive bacterial infection among high-frequency injection drug users

Background

Bacterial infection is a major cause of morbidity and mortality for persons who inject drugs (PWID). Injection cessation may help abrogate such infections, but maintaining complete cessation is challenging. Limited data exists on the role of reduced injection intensity on invasive bacterial infection risk. We sought to evaluate decreased risk for bacterial infections following cessation and substantive reduction in the injection intensity.

Methods

Participants were persons in the AIDS Linked to the Intravenous Experience (ALIVE) cohort with initial high-frequency injection drug use (> 1 daily). Pooled logistic regression with generalized estimating equations was used to estimate risk for invasive bacterial infection (pneumonia, endocarditis, or sepsis) among participants achieving complete injection cessation or reduced injection intensity relative to those with sustained high-frequency use.

Results

Of 2247 study participants with 12,469 paired study visits, complete injection cessation was achieved at 13.5% and reduced injection intensity at 25.5% of study visits. Adjusting for sociodemographics and HIV status, injection cessation was associated with a 54% reduction of bacterial infection at 3 months (odds ratio [OR] 0.46, 95% CI 0.25–0.84) and a 46% reduction at 6 months (OR 0.54, 95% CI 0.36–0.81). Reduced injection intensity was associated with a 36% reduction of infection at 3 months (OR 0.64, 95% CI 0.43–0.96) and a 26% reduction at 6 months (OR 0.74, 95% CI 0.56–0.98).

Conclusions

Both complete cessation and reduced injection frequency demonstrate substantial benefit in reducing invasive bacterial infection risk among PWID. With high rates of relapse into injection use, targeting sustained reductions in drug use intensity may be a key harm reduction modality for improving clinical outcomes in this population.

Electronic supplementary material

The online version of this article (10.1186/s12954-019-0312-8) contains supplementary material, which is available to authorized users.

Evaluating the cost-effectiveness of existing needle and syringe programmes in preventing hepatitis C transmission in people who inject drugs

AIM

To evaluate the cost-effectiveness of needle and syringe programmes (NSPs) compared with no NSPs on hepatitis C virus (HCV) transmission in the United Kingdom.

DESIGN

Cost-effectiveness analysis from a National Health Service (NHS)/health-provider perspective, utilizing a dynamic transmission model of HCV infection and disease progression, calibrated using city-specific surveillance and survey data, and primary data collection on NSP costs. The effectiveness of NSPs preventing HCV acquisition was based on empirical evidence.

SETTING AND PARTICIPANTS

UK settings with different chronic HCV prevalence among people who inject drugs (PWID): Dundee (26%), Walsall (18%) and Bristol (45%) INTERVENTIONS: Current NSP provision is compared with a counterfactual scenario where NSPs are removed for 10 years and then returned to existing levels with effects collected for 40 years.

MEASUREMENTS

HCV infections and cost per quality-adjusted life year (QALY) gained through NSPs over 50 years.

FINDINGS

Compared with a willingness-to-pay threshold of £20 000 per QALY gained, NSPs were highly cost-effective over a time-horizon of 50 years and decreased the number of HCV incident infections. The mean incremental cost-effectiveness ratio was cost-saving in Dundee and Bristol, and £596 per QALY gained in Walsall, with 78, 46 and 40% of simulations being cost-saving in each city, respectively, with differences driven by coverage of NSP and HCV prevalence (lowest in Walsall). More than 90% of simulations were cost-effective at the willingness-to-pay threshold. Results were robust to sensitivity analyses, including varying the time-horizon, HCV treatment cost and numbers of HCV treatments per year.

CONCLUSIONS

Needle and syringe programmes are a highly effective low-cost intervention to reduce hepatitis C virus transmission, and in some settings they are cost-saving. Needle and syringe programmes are likely to remain cost-effective irrespective of changes in hepatitis C virus treatment cost and scale-up.

The experiences of people who inject drugs of skin and soft tissue infections and harm reduction: A qualitative study

BACKGROUND

Bacterial skin and soft tissue infections (SSTI) among people who inject drugs (PWID) are considered a public health concern. There is a lack of qualitative research examining the lived experience of PWID who have had SSTI. This paper explores PWID views and experiences of their SSTI, their perceptions on the causes of their SSTI and their harm reduction (HR) behaviours. The implications for HR service delivery and practice will be discussed.

METHODS

Between October 2015-January 2016, 22 in-depth interviews were conducted with PWID who had experienced a SSTI within the past year. Interviewees were recruited from an injecting equipment provision service and a drug treatment service in Glasgow and Edinburgh respectively. The interview transcripts were transcribed verbatim and underwent thematic analysis.

RESULTS

We found that the experience of SSTI can cause strong negative feelings, including panic and stigma and that there was limited knowledge of SSTI prior to first hand experience. The awareness of the unacceptable social and physical consequences of SSTI fostered a sense of personal responsibility and agency which led to the introduction or improved HR uptake. However, when PWID were struggling to inject or when their physical and political environments were compromised there was an increased risk for SSTI and reduced effectiveness of HR.

CONCLUSION

Compared to HCV and HIV, SSTI as an injecting related harm has received less policy attention. Policy makers need to address SSTI HR within enabling environments, such as 'safer environment interventions'. It is recommended that peer based support, improved NSP provision and medically supervised injecting facilities are needed to deliver SSTI HR.

Changes in supervised drug-injecting practices following a community-based educational intervention: A longitudinal analysis

BACKGROUND

People who inject drugs face several health issues because of unsafe injecting practices. We aimed to evaluate changes in supervised drug-injecting practices following the implementation of a face-to-face educational intervention.

METHODS

The national study ANRS-AERLI was conducted in 17 harm reduction (HR) facilities in France between 2011 and 2013. Eight offered the intervention and nine did not. We conducted a pre-post analysis focusing on injecting practices data, collected in the 8 HR facilities providing the intervention. The intervention consisted of providing face-to-face educational sessions including direct observation of injecting practices, counseling about safer injecting, and shared discussion. Injecting practices were collected following a checklist and classified as safe or unsafe. To assess changes in injecting practices, practices were compared before (at baseline) and after at least one educational session.

FINDINGS

Mixed logistic models showed that the 78 participants included were more likely to improve in the following drug-use steps: setting up a clean preparation area (Adjusted Odds Ratio (AOR) = 3.4, 95% Confidence Interval (95% CI) = 1.6-7.6), hand washing (AOR = 7.2, 95% CI = 3.1-16.4), skin cleaning (AOR = 5.6, 95% CI = 2.5-12.1), choice of safe injection site (AOR = 6.5, 95% CI = 1.5-28.8) and post-injection bleeding management (AOR = 12.8, 95% CI = 5.5-29.9). Furthermore, participants were less likely to lick their needles before injecting (AOR = 8.1, 95% CI = 1.5-43.4) and to perform booting/flushing (AOR = 2.5, 95% CI = 1.2-5.3).

CONCLUSIONS

The AERLI intervention seems to be effective in increasing safe drug-injecting practices.

Drawing attention to a neglected injecting-related harm: a systematic review of AA amyloidosis among people who inject drugs

BACKGROUND AND AIMS

Chronic skin and soft tissue infections (SSTI) among people who inject drugs (PWID) can lead to AA amyloidosis: a serious, yet neglected, multi-organ disease. We aim to synthesize findings on the epidemiology, risk factors, clinical outcomes, screening recommendations and challenges to treatment for AA amyloidosis among PWID.

METHODS

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched the following bibliographic databases in July 2017: CINAHL Plus, Embase, Global Health, MEDLINE, PsycEXTRA, PsycINFO and SCOPUS. Studies were included if they investigated AA amyloidosis in PWID. Studies were not restricted to location, study type, year or language of publication. Study heterogeneity precluded meta-analysis; we present a narrative review of the literature.

RESULTS

Thirty-seven papers from eight countries met inclusion criteria. A total of 781 PWID are reported on, of whom 177 had AA amyloidosis. Where disease causality is established, it is attributed to chronic inflammation caused by injecting-related SSTIs. Most (88.7%) PWID with AA amyloidosis had SSTIs. The proportion of PWID with AA amyloidosis at post-mortem ranged from 1.6% (Germany) to 22.5% (Serbia). Biopsy studies reported from 5.26% (Portugal) to 50% (Germany) of AA amyloidosis in PWID with suspected or known kidney disease. Following diagnosis, the typical trajectory for PWID with AA amyloidosis was rapid deterioration of renal function requiring haemodialysis. Treatment difficulties, end-stage renal failure and premature death from sepsis were observed. Good outcomes, including reversibility of AA amyloidosis, are attributed to rapid treatment of the underlining inflammation and injecting cessation. Notably, given the population in question, no studies were published in addiction or harm reduction journals; most (92%) appeared in specialist nephrology and medical journals.

CONCLUSION

There is strong evidence of an association between skin and soft tissue infections (SSTIs) and AA amyloidosis. Among people who inject drugs, injecting-related SSTIs are a significant cause of morbidity and premature mortality and there is evidence of increasing SSTI prevalence. Limitations in the literature make it difficult to estimate AA amyloidosis prevalence among people who inject drugs.

Risk Factors Associated With Skin and Soft Tissue Infections Among Hospitalized People Who Inject Drugs

OBJECTIVES

Skin and soft tissue infections (SSTIs) are common among people who inject drugs (PWID), and can lead to serious morbidity and costly emergency room and hospital utilization. A range of high-risk injection practices may contribute to these infections. The goal of the current study was to examine risk practices that were associated with SSTIs in a sample of hospitalized PWID.

METHODS

PWID (N = 143; 40.6% female) were recruited from inpatient medical units at a large urban hospital and completed a baseline interview that focused on infection risk. Measures included demographics, substances used/injected, and self-report of SSTIs (ie, abscesses, ulcers, or cellulitis) within the past year. The Bacterial Infections Risk Scale for Injectors-a 7-item index-assessed specific behaviors expected to increase the risk of acquiring SSTIs (eg, injection without skin cleaning, intramuscular injection).

RESULTS

The sample was 58% Caucasian and averaged 38.7 (SD = 10.7) years of age. Ninety-three participants (65%) reported at least 1 SSTI within the past year. Using a logistic regression model, the Bacterial Infections Risk Scale for Injectors (odds ratio 1.87, P = 0.004) and total number of injections over the past 3 months (odds ratio 2.21, P = 0.002) were associated with past year SSTIs.

CONCLUSIONS

In conclusion, rates of past-year SSTIs were high in this sample of hospitalized PWID. Results suggest that interventions should target specific injection practices to reduce infection risk.

Experiences with skin and soft tissue infections among people who inject drugs in Philadelphia: A qualitative study

OBJECTIVES

To understand how people who inject drugs (PWID) experience skin and soft tissue infections (SSTI) and make decisions to seek or delay medical treatment.

METHODS

We conducted semi-structured, in-depth interviews in 2015 with 19 PWID at a syringe exchange program in Philadelphia. We analyzed the data using standard qualitative techniques.

RESULTS

PWID described adequate knowledge about SSTI, although they could not always implement knowledge about SSTI prevention due to environmental constraints. Participants reported different experiences with incident SSTI. Some sought immediate medical care at initial presentation. Most, however, waited to seek care. Previous positive and negative healthcare experiences, both in general -including stigma and withdrawal- and specific to SSTI, influenced this decision. Among those who delayed medical care, some reported self-treatment, including increased drug use for pain control, and lancing and draining their own wounds.

CONCLUSION

Reducing the incidence of SSTI and promoting earlier treatment are important public health priorities. Both require ongoing attention and improvements to the environments in which PWID inject and receive care.

Both localized and systemic bacterial infections are predicted by injection drug use: A prospective follow-up study in Swedish criminal justice clients

Background

Both skin and soft tissue infections (SSTI) and systemic bacterial infections are common in people who inject drugs (PWID), but data on incidence and risk factors are lacking. We compared registered diagnoses for such infections in Swedish criminal justice clients with regard to injecting drug use.

Methods

Baseline interview data from the Swedish Prison and Probation Service on drug use in PWID and non-PWID with problematic alcohol use were linked to follow-up data from national Swedish registers on hospital diagnoses and/or death. Associations between drug use and later diagnosis of SSTI and systemic bacterial infection (septicemia or bacterial infection of the heart, bone/joints or central nervous system) were analyzed by Cox regression.

Results

Incidence rates of SSTI was 28.3 per 1,000 person-years for PWID (n = 2,444) and 10.0 for non-PWID with problematic alcohol use (n = 735). Incidence rates of systemic bacterial infection was 9.1 per 1,000 person-years for PWID and 2.7 per 1,000 person-years for non-PWID. Injection drug use was associated with a significantly increased risk of bacterial infections, for main drugs heroin (SSTI: Hazard ratio [HR] 2.45; systemic infection: HR 2.75), amphetamine (SSTI: HR 1.60; systemic infection: HR 2.19), and polysubstance use (SSTI: HR 1.92; systemic infection: HR 2.01). In relation to injection use of amphetamine and polysubstance use, PWID mainly using heroin had higher risk of SSTI.

Conclusions

Injection drug use predicted both SSTI and systemic bacterial infection, with a particularly high risk of SSTI in PWID mainly using heroin. The results imply the need for increased attention to bacterial infections among PWID, in terms of clinical management, prevention and research.

Prevalence and risk factors for injection site skin infections among people who inject drugs (PWID) in Tehran

BACKGROUND/OBJECTIVES

Injection drug use is one of the major public health problems in Iran. Injection drug use is associated with numerous negative health outcomes, such as blood-borne infections (HIV, HCV) and injection site skin infections (abscesses, cellulitis). The aim of this study was to determine prevalence of injection site skin infections and its associated risk factors among people who inject drugs (PWID) in Tehran, Iran.

METHODS

The cross-sectional study was conducted from March to August 2016 in Tehran province. A total of 500 PWID were recruited by convenience and snowball sampling from Drop-in Centers (DIC) in the South of Tehran. Our primary outcomes were self-report of ever having injection sites skin infections and receiving treatment for them. We first examined associations between individual variables and lifetime history of having injection site infections in bivariate analysis using the chi-square or Fisher's exact tests, as appropriate. Variables with P-value <.2 were included in a multiple logistic regression model.

RESULTS

Overall, 40% (CI95%: 30.3%, 52.2%) of participants reported ever having an injection site infection. In the multivariable model, those with low socioeconomic status (AOR = 2.4, P = .03), self-reported as HIV positive (AOR =1.6, P = .01), reporting more than 3 injections per day (AOR = 4.1, P = .03) and reuse of their own syringes (AOR = 8.5, P = .03) were more likely to have injection sites skin infections. PWID who used needle and syringe program (NSP) services were less likely to report injection site infections (AOR = 0.5, P = .04).

CONCLUSION

We have identified several risk factors for injection sites infections among PWID, including frequency of injection per day, reuse of their own syringes, not using NSP services, HIV status, socioeconomic status with skin infections in PWID. Prevention strategies to reduce skin infections should focus on high-risk injection behaviors and improving access to NSP services.

'Care and Prevent': rationale for investigating skin and soft tissue infections and AA amyloidosis among people who inject drugs in London

BACKGROUND

Skin and soft tissue infections (SSTIs) are a leading cause of morbidity and mortality among people who inject drugs (PWID). International data indicate up to one third of PWID have experienced an SSTI within the past month. Complications include sepsis, endocarditis and amyloid A (AA) amyloidosis. AA amyloidosis is a serious sequela of chronic SSTI among PWID. Though there is a paucity of literature reporting on AA amyloidosis among PWID, what has been published suggests there is likely a causal relationship between AA amyloidosis and injecting-related SSTI. If left untreated, AA amyloidosis can lead to renal failure; premature mortality among diagnosed PWID is high. Early intervention may reverse disease. Despite the high societal and individual burden of SSTI among PWID, empirical evidence on the barriers and facilitators to injecting-related SSTI prevention and care or the feasibility and acceptability of AA amyloidosis screening and treatment referral are limited. This study aims to fill these gaps and assess the prevalence of AA amyloidosis among PWID.

METHODS

Care and Prevent is a UK National Institute for Health Research-funded mixed-methods study. In five phases (P1-P5), we aim to assess the evidence for AA amyloidosis among PWID (P1); assess the feasibility of AA amyloidosis screening, diagnostic and treatment referral among PWID in London (P2); investigate the barriers and facilitators to AA amyloidosis care (P3); explore SSTI protection and risk (P4); and co-create harm reduction resources with the affected community (P5). This paper describes the conceptual framework, methodological design and proposed analysis for the mixed-methods multi-phase study.

RESULTS

We are implementing the Care and Prevent protocol in London. The systematic review component of the study has been completed and published. Care and Prevent will generate an estimate of AA amyloidosis prevalence among community recruited PWID in London, with implications for the development of screening recommendations and intervention implementation. We aim to recruit 400 PWID from drug treatment services in London, UK.

CONCLUSIONS

Care and Prevent is the first study to assess screening feasibility and the prevalence of positive proteinuria, as a marker for AA amyloidosis, among PWID accessing drug treatment services. AA amyloidosis is a serious, yet under-recognised condition for which early intervention is available but not employed.

Opiate Injection-Associated Skin, Soft Tissue, and Vascular Infections, England, UK, 1997-2016

In England, UK, hospital admissions caused by bacterial infections associated with opioid use have increased annually since 2012, after 9 years of decline, mirroring trends in overdose deaths. The increase occurred among persons of both sexes and in all age groups and suggests preventive measures need reviewing.

Health outcomes associated with crack-cocaine use: Systematic review and meta-analyses

BACKGROUND

Crack-cocaine use is prevalent largely in socio-economically marginalized populations in the Americas. Its use has been associated with diverse health outcomes, yet no recent or systematic reviews of these exist.

METHODS

A systematic review of health outcomes associated with crack-cocaine use was performed, using MEDLINE, Scopus, Web of Science, CINAHL, PsycINFO, and LILACS up to October 2016. Search terms included crack-cocaine and health outcome-related keywords, targeting peer-reviewed studies on quantified health outcomes associated with crack-cocaine use. Random effects meta-analyses produced pooled odds ratios. Levels of evidence for major results were assessed using the GRADE approach. A review protocol was registered with PROSPERO (CRD42016035486).

RESULTS

Of 4700 articles returned, 302 met eligibility criteria, reporting on health outcomes for 14 of 22 ICD-10 chapters. Conclusive evidence and meta-analyses showed positive associations between crack-cocaine use and blood/sexually transmitted diseases (HIV and hepatitis C virus, others); moderate evidence and meta-analyses supported associations with neonatal health, and violence. There were mixed associations for mental and other health outcomes, yet insufficient evidence to perform meta-analyses for many categories (e.g., mortality). Most underlying research was of limited or poor quality, with crack-cocaine commonly assessed as a secondary covariate.

CONCLUSIONS

Crack-cocaine use was associated with a range of health outcomes, although it was unclear if there was direct causal impact, interactions between risk factors, or external drivers of both crack-cocaine use and outcomes. Rigorous epidemiological studies are needed to systematically assess health outcomes of crack-cocaine use and underlying pathways, also to inform evidence-based interventions.

Evaluation of an online injecting drug use stigma intervention targeted at health providers in New South Wales, Australia

People who inject drugs are highly stigmatised. Discriminatory experiences are commonly reported, particularly in health care settings. This article evaluates an online stigma reduction training module targeting health providers working with people who inject drugs. A total of 139 participants completed a pre- and post-survey including attitude items and items depicting hypothetical scenarios and concerns around client behaviours. Participants' attitudes towards people who inject drugs were more positive and they showed less concerns about client behaviours after completing the online training module. Findings highlight the benefits of online training in reducing discriminatory attitudes towards people who inject drugs and improving confidence in working with this client group.

Association between harm reduction intervention uptake and skin and soft tissue infections among people who inject drugs

BACKGROUND

Bacterial skin and soft tissue infections (SSTIs) are a health issue for people who inject drugs (PWID). There is a lack of evidence on the associations between harm reduction (HR) uptake and SSTIs. This paper examines the associations between the uptake of injecting equipment (IE) and opiate substitution treatment (OST) on SSTIs among PWID, and the injecting behaviours associated with having had an SSTI. This is the first large-scale, national study to examine the association between IE uptake and SSTIs.

METHODS

A cross-sectional, voluntary and anonymous survey was undertaken with PWID recruited from pharmacies/agencies providing IE across mainland Scotland during 2013-2014. Participants were asked: if they had an SSTI within the past year; about their uptake of HR within the past 6 months (including needle/syringes (N/S), paraphernalia and OST); and about their frequency of injecting, sharing of IE and re-use of own N/S. Data from 1876 PWID who had reported injecting within the past 6 months were analysed.

FINDINGS

In multivariate logistic regression, those with high combined IE-OST uptake (adjusted odds ratio [AOR] 0.614, 95% CI 0.458-0.823, p=0.001) and medium combined IE-OST uptake (AOR 0.725, 95% CI 0.546-0.962, p=0.026) had lower odds of having had an SSTI compared to those with low combined IE-OST uptake.

CONCLUSIONS

IE and OST uptake may reduce the level of SSTIs among PWID, suggesting increasing combined uptake may be beneficial. Nevertheless, a sizeable proportion of PWID with high HR uptake experienced SSTIs, suggesting the importance of other interventions.

Are the testing needs of key European populations affected by hepatitis B and hepatitis C being addressed? A scoping review of testing studies in Europe

Aim

To investigate whether or not key populations affected by hepatitis B and hepatitis C are being tested sufficiently for these diseases throughout the European region.

Methods

We searched MEDLINE and EMBASE for studies on HBV and HCV testing in the 53 Member States of the World Health Organization European Region following PRISMA criteria.

Results

136 English-language studies from 24 countries published between January 2007 and June 2013 were found. Most studies took place in 6 countries: France, Germany, Italy, the Netherlands, Turkey, and the United Kingdom. 37 studies (27%) addressed HBV, 46 (34%) HCV, and 53 (39%) both diseases. The largest categories of study populations were people who use drugs (18%) and health care patient populations (17%). Far fewer studies focused on migrants, prison inmates, or men who have sex with men.

Conclusions

The overall evidence base on HBV and HCV testing has considerable gaps in terms of the countries and populations represented and validity of testing uptake data. More research is needed throughout Europe to guide efforts to provide testing to certain key populations.

A systematic review of injecting-related injury and disease among people who inject drugs

BACKGROUND

Non-viral injecting-related injuries and diseases (IRID), such as abscesses and vascular damage, can result in significant morbidity and mortality if untreated. There has been no systematic assessment of the prevalence of non-viral IRID among people who inject drugs; this review aimed to address this gap, as well as identify risk factors for experience of specific IRID.

METHODS

We searched MEDLINE, Embase and CINAHL databases to identify studies on the prevalence of, or risk factors for, IRID directly linked to injecting in samples of people who inject illicit drugs.

RESULTS

We included 33 studies: 29 reported IRID prevalence in people who inject drugs, and 17 provided data on IRID risk factors. Skin and soft tissue infections at injecting sites were the most commonly reported IRID, with wide variation in lifetime prevalence (6-69%). Female sex, more frequent injecting, and intramuscular and subcutaneous injecting appear to be associated with skin and soft tissue infections at injecting sites. Cleaning injecting sites was protective against skin infections. Other IRID included infective endocarditis (lifetime prevalence ranging from 0.5-12%); sepsis (2-10%); bone and joint infections (0.5-2%); and thrombosis and emboli (3-27%).

CONCLUSIONS

There were significant gaps in the data, including a dearth of research on prevalence of IRID in low- and middle-income countries, and potential risk and protective factors for IRID. A consistent approach to measurement, including standardised definitions of IRID, is required for future research.