Changes in the development of opioid tolerance on re-exposure among people who use heroin: A qualitative study.

BACKGROUND AND AIMS: This qualitative study aimed to explore how the development of tolerance to both the psychoactive and respiratory depressant effects of heroin on re-exposure are experienced by people who use heroin. METHODS: Semi-structured one-to-one interviews were conducted with 20 adults who currently or previously used heroin (for at least 6 months), with any type of administration (injected, smoked) and experience of abstinence (at least 2 weeks) and relapse. Topic guides explored the participants understanding of tolerance, their experience of developing tolerance to heroin and of tolerance following relapse. Interviews were audio-recorded and transcribed. Thematic analysis was used to generate salient themes. RESULTS: The analysis produced three broad themes: lay understanding of tolerance; tolerating tolerance; and rapid tolerance development following relapse. Tolerance was defined as the body adapting to regular drug use, so that the drug no longer produced the same level of effect. Tolerance was experienced as interacting and co-developing with physical dependence and the symptoms of withdrawal. Indeed, several participants did not differentiate between tolerance and dependence. Most participants did not notice tolerance to respiratory depression. Tolerance levels fluctuated-increasing over periods of regular use and reducing when abstinent. Using more drug was the most common response to increasing tolerance to the desired effects. On re-use following abstinence, tolerance was experienced as developing more quickly in the most recent relapse compared to the first. Tolerance was also perceived to return more quickly with each abstinence-relapse cycle. CONCLUSIONS: Qualitative accounts of tolerance report that tolerance returns more quickly with each relapse episode. By elucidating the mechanism(s) involved and potentially discovering how they could be switched on prior to relapse occurring we might be able to develop a beneficial harm reduction treatment for people in abstinence that would protect against overdose occurring on subsequent relapse.

Acceptability of, and barriers and facilitators to, a pilot physical health service for people who inject drugs: A qualitative study with service users and providers.

BACKGROUND: People who inject drugs may experience difficulty accessing or maintaining involvement with traditional healthcare services. This is associated with increased health inequalities and bio-psychosocial difficulties. Embedding physical healthcare services within community-based drug services may provide a practical and feasible approach to increase access and delivery of healthcare. This study explored the acceptability of, and barriers and facilitators to, embedding a pilot physical healthcare service within a community-based drug service in the United Kingdom (Bristol, England). METHODS: Semi-structured interviews were conducted with service users (people who inject drugs) (n = 13), and a focus group was conducted with service providers (n = 11: nine harm reduction workers, two nurses, one service manager). Topic guides included questions to explore barriers and facilitators to using and delivering the service (based on the COM-B Model), and acceptability of the service (using the Theoretical Framework of Acceptability). Transcripts were analysed using a combined deductive framework and inductive thematic analysis approach. RESULTS: The service was viewed as highly acceptable. Service users and providers were confident they could access and provide the service respectively, and perceived it to be effective. Barriers included competing priorities of service users (e.g. drug use) and the wider service (e.g. equipment), and the potential impact of the service being removed in future was viewed as a barrier to overall healthcare access. Both service users and providers viewed embedding the physical health service within an existing community-based drug service as facilitating accessible and holistic care which reduced stigma and discrimination. CONCLUSIONS: The current study demonstrated embedding a physical health service within an existing community-drug based and alcohol service was acceptable and beneficial. Future studies are required to demonstrate cost-effectiveness and ensure long-term sustainability, and to determine transferability of findings to other settings, organisations and countries.

Perceived availability and carriage of take-home naloxone and factors associated with carriage among people who inject drugs in England, Wales and Northern Ireland.

BACKGROUND: In 2019-2020, record-high numbers of overdoses have been reported across the UK. We estimated perceived availability to and carriage of naloxone and explored factors associated with carriage among people who inject drugs (PWID) engaged with services in England, Wales, and Northern Ireland. METHODS: Participants were PWID enrolled in the Unlinked Anonymous Monitoring Survey in 2019 who reported past-year injection drug use (n = 2,139). Recruitment occurred through specialist and community drug agencies located across the UK, excluding Scotland. Socio-demographic, behavioural and service use characteristics were self-reported. Participants were asked whether they carry naloxone (timeframe unspecified). If they answered "no", they were further asked whether it is available in their area. Perceived naloxone availability and carriage were estimated by requirement region, classified using the Nomenclature of Territorial Units for Statistics 1. We used the Gelberg-Andersen Model of healthcare access to explore predisposing, enabling and need factors associated with regionally-aggregated naloxone carriage. RESULTS: Perceived naloxone availability was ≥95% in all 11 regions; naloxone carriage varied (mean: 61.1; range: 48%-71%; P<0.01). Among predisposing factors, female gender (adjusted odds ratio (AOR): 1.52; 95% confidence interval (CI): 1.21-1.91) was positively associated with naloxone carriage, whilst recruitment in Yorkshire and the Humber-relative to London-was negatively associated (AOR: 0.55; 95%CI: 0.37-0.82). Among enabling factors, past-year contact with needle and syringe programmes (AOR: 1.74; 95%CI: 1.39-2.18) and currently receiving treatment for drug use (AOR: 1.75; 95%CI: 1.24-2.46) were positively associated with naloxone carriage. Among need characteristics, past-month heroin injection, with or without past-month high-risk drinking or benzodiazepine use, was positively associated with carriage relative to no heroin injection (range of AORs: 1.71-2.58). CONCLUSION: Perceived naloxone availability is very high among PWID attending services in England, Wales, and Northern Ireland. Naloxone carriage is moderately high and varying across regions, and appears improved through recent engagement with harm-reduction programs.

Living Under Coronavirus and Injecting Drugs in Bristol (LUCID-B): A qualitative study of experiences of COVID-19 among people who inject drugs.

BACKGROUND: People who inject drugs (PWID) are a high-risk group for COVID-19 transmission and serious health consequences. Restrictions imposed in the UK in response to the pandemic led to rapid health and housing service alterations. We aimed to examine PWID experiences of: 1) challenges relating to the COVID-19 public health measures; 2) changes to opioid substitution therapy (OST) and harm reduction services; and 3) perceived effects of COVID-19 on drug use patterns and risk behaviour. METHODS: Telephone semi-structured interviews were conducted with 28 PWID in Bristol, Southwest of England. Analysis followed a reflexive thematic analysis. RESULTS: Concern about COVID-19 and adherence to public health guidance varied. Efforts made by services to continue providing support during the pandemic were appreciated and some changes were preferred, such as less frequent OST collection, relaxation of supervised consumption and needle and syringe programmes (NSP) home delivery. However, remote forms of contact were highlighted as less beneficial and more difficult to engage with than in-person contact. Public health guidance advising people to 'stay home' led to increased isolation, boredom, and time to ruminate which impacted negatively on mental health. Lockdown restrictions directly impacted on sources of income and routine. Changes in drug use were explained as a consequence of isolation and fewer interactions with peers, problems accessing drugs, reduced drug purity and reduced financial resources. CONCLUSION: This study captures the significant impacts and challenges of the COVID-19 pandemic on the lives of PWID. While rapid adaptations to service delivery to help mitigate the risks of COVID-19 were appreciated and some changes such as relaxation of supervised daily OST consumption were viewed positively, barriers to access need further attention. Going forwards there may be opportunities to harness the positive aspects of some changes to services.

Detachable low dead space syringes for the prevention of hepatitis C among people who inject drugs in Bristol, UK: an economic evaluation.

BACKGROUND AND AIMS: Traditional detachable syringes used by people who inject drugs (PWID) retain larger volumes of blood when the plunger is depressed than syringes with fixed needles-referred to as high (HDSS) and low dead space syringes (LDSS), respectively. Evidence suggests that using HDSS may result in greater hepatitis C virus (HCV) transmission risk than LDSS. We evaluated the cost-effectiveness of an intervention to introduce detachable LDSS in a needle and syringe programme (NSP). DESIGN: HCV transmission and disease progression model with cost-effectiveness analysis using a health-care perspective. Detachable LDSS are associated with increased costs (£0.008) per syringe, yearly staff training costs (£536) and an estimated decreased risk (by 47.5%) of HCV transmission compared with HDSS. The intervention was modelled for 10 years, with costs and health benefits (quality-adjusted life-years: QALYs) tracked over 50 years. SETTING: Bristol, UK. PARTICIPANTS AND CASES: PWID attending NSP. INTERVENTION AND COMPARATOR: Gradual replacement of HDSS at NSP, with 8, 58 and 95% of HDSS being replaced by detachable LDSS in 2016, 2017 and 2018, respectively. Comparator was continuing use of HDSS. MEASUREMENTS: Net monetary benefit. Benefits were measured in QALYs. FINDINGS: Introducing detachable LDSS was associated with a small increase in intervention costs (£21 717) compared with not introducing detachable LDSS, but considerable savings in HCV-related treatment and care costs (£4 138 118). Overall cost savings were £4 116 401 over 50 years and QALY gains were 1000, with an estimated 30% reduction in new infections over the 10-year intervention period. In all sensitivity analyses, detachable LDSS resulted in cost savings and additional QALYs. Threshold analyses suggested that detachable LDSS would need to reduce HCV transmission risk of HDSS by 0.26% to be cost-saving and 0.04% to be cost-effective. CONCLUSIONS: Replacing high dead space syringes with detachable low dead space syringes in needle and syringe programmes in the United Kingdom is likely to be a cost-saving approach for reducing hepatitis C virus transmission.

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.

Impact of current and scaled-up levels of hepatitis C prevention and treatment interventions for people who inject drugs in three UK settings-what is required to achieve the WHO's HCV elimination targets?

AIMS: To estimate the impact of existing high-coverage needle and syringe provision (HCNSP, defined as obtaining more than one sterile needle and syringe per injection reported) and opioid substitution therapy (OST) on hepatitis C virus (HCV) transmission among people who inject drugs (PWID) in three UK settings and to determine required scale-up of interventions, including HCV treatment, needed to reach the World Health Organization (WHO) target of reducing HCV incidence by 90% by 2030. DESIGN: HCV transmission modelling using UK empirical estimates for effect of OST and/or HCNSP on individual risk of HCV acquisition. SETTING AND PARTICIPANTS: Three UK cities with varying chronic HCV prevalence (Bristol 45%, Dundee 26%, Walsall 19%), OST (72-81%) and HCNSP coverage (28-56%). MEASUREMENTS: Relative change in new HCV infections throughout 2016-30 if current interventions were stopped. Scale-up of HCNSP, OST and HCV treatment required to achieve the WHO elimination target. FINDINGS: Removing HCNSP or OST would increase the number of new HCV infections throughout 2016 to 2030 by 23-64 and 92-483%, respectively. Conversely, scaling-up these interventions to 80% coverage could achieve a 29 or 49% reduction in Bristol and Walsall, respectively, whereas Dundee may achieve a 90% decrease in incidence with current levels of intervention because of existing high levels of HCV treatment (47-58 treatments per 1000 PWID). If OST and HCNSP are scaled-up, Walsall and Bristol can achieve the same impact by treating 14 or 40 per 1000 PWID annually, respectively (currently two and nine treatments per 1000 PWID), while 18 and 43 treatments per 1000 PWID would be required if OST and HCNSP are not scaled-up. CONCLUSIONS: Current opioid substitution therapy and high-coverage needle and syringe provision coverage is averting substantial hepatitis C transmission in the United Kingdom. Maintaining this coverage while getting current drug injectors onto treatment can reduce incidence by 90% by 2030.

Acceptability of low dead space syringes and implications for their introduction: A qualitative study in the West of England.

BACKGROUND: It is recommended that needle and syringe programmes (NSP) distribute low dead space syringes (LDSS) to reduce blood-borne virus transmission. We explored the acceptability of detachable LDSS among people who inject drugs (PWID) and staff who work to support them. METHODS: Semi-structured interviews were performed with 23 PWID (15 men and 8 women) and 13 NSP staff members (6 men and 7 women) in Bath and Bristol, England. Recruited PWID reflected varying demographic characteristics, drug use and injecting preferences. Interviews explored experiences of different types of injecting equipment, facilitators and barriers of changing this equipment and attitudes towards detachable LDSS. Interviews were audio recorded, transcribed verbatim and analysed using the Framework Method. RESULTS: Decisions about injecting practices were underpinned by several factors, including early experiences and peer initiation; awareness and availability of alternatives; and the ability to inject successfully. Rinsing and re-using syringes represented a quandary where rinsing could encourage re-use, but not rinsing could result in the re-use of unclean equipment. Most PWID were reluctant to change equipment particularly in the absence of any problems injecting. Prioritising getting a 'hit' over the prevention of potential problems was an important barrier to change. Overall detachable LDSS are likely to be acceptable. Lower risk of transferring infections and reduced drug wastage were valued benefits of detachable LDSS. There was a preference for a gradual introduction of detachable LDSS in which PWID are given an opportunity to try the new equipment alongside their usual equipment. CONCLUSION: Detachable LDSS are likely to be acceptable and should therefore be offered to those using detachable high dead space syringes and/or fixed 1ml LDSS syringes to inject into deeper femoral veins. An intervention is needed to support their introduction with 'training', 'education', 'persuasion' and eventual 'restriction' components.

Enhancing motivation within a rapid opioid substitution treatment feasibility RCT: a nested qualitative study.

BACKGROUND: Opioid substitution treatment (OST) has multiple benefits for heroin injectors and is an evidence-based major component of international treatment. The current qualitative study sought to explore participants' attitudes to and reasons for participating in a feasibility randomised trial in primary care offering 'same day' OST (methadone) for injecting heroin users compared to usual care. METHODS: Twenty injecting heroin users (8 intervention and 12 controls; 16 males and 4 females) were interviewed; purposive sampling was used to select a maximum variation sample from those who agreed; and analysis used thematic methods. RESULTS: Motivation to join the trial included the need to secure treatment set against some ambivalence due to previous negative experiences of trying to obtain OST. Positive effects of securing methadone via the trial, included self-reported improvements in health and self-care; reduction in crime, stress and drug use. Completing the baseline questionnaires at recruitment appeared to enhance motivation for treatment for all participants. For some control participants, this motivation seemed to increase a sense of self-efficacy and cognitive dissonance generated was resolved by seeking treatment from their GP. Self-determination theory suggests that behaviour change may have been initiated during the recruitment appointment, resulting in an increased determination to seek treatment amongst control participants. CONCLUSIONS: Taking part in the 'script in a day' trial enabled participants in the intervention arm to gain same-day access to methadone and reduce their drug use. For those in the control arm, completing the baseline questionnaires at recruitment appeared to create cognitive dissonance between their current health state and own aspirations, so increasing motivation for treatment. Over 50% obtained and were still in receipt of OST (methadone or buprenorphine) at the 3 month follow-up. We suggest that a regular 'health evaluation' for injecting heroin users not in treatment, paired with low-barrier access to treatment, may be a way of exploring this and encouraging more into obtaining OST more quickly and at the best time for them. This intervention should be delivered without pressure for change. CLINICAL TRIAL REGISTRATION: This trial is registered with International Standard Randomised Controlled Trial Number Register: SCript In a Day for injecting drug users: feasibility trial: ISRCTN16846554.