High Dead Space Syringes Research Articles

Commentary on Hancock et al. (2020): Low dead space syringes are just one component of an integrated package of care needed to tackle HCV and social exclusion among people who inject drugs.

Commentary on Hancock et al. (2020): Low dead space syringes are just one component of an integrated package of care needed to tackle HCV and social exclusion among people who inject drugs.

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

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). 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 10years, with costs and health benefits (quality-adjusted life-years: QALYs) tracked over 50years. Bristol, UK. PWID attending NSP. 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. Net monetary benefit. Benefits were measured in QALYs. 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 50years 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. 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.

Usage of low dead space syringes and association with hepatitis C prevalence amongst people who inject drugs in the UK

IntroductionSyringes with attached needles (low dead space syringes [LDSS]) retain far less blood following injection than syringes with detachable needles (high dead space syringes [HDSS]). People who inject drugs (PWID) who share needles/syringes may be less likely to acquire Hepatitis C virus (HCV) infection using LDSS, compared with HDSS, but data are limited. MethodsUtilizing drug behavior and HCV antibody testing data from the UK 2014/2015 Unlinked Anonymous Monitoring Survey of PWID, we calculated the percentage of syringes used in the past month that were LDSS. We investigated which injecting characteristics and demographic factors were associated with 100% LDSS (against 0–99%) usage, and whether 100% LDSS use was associated with antibody HCV-status, after adjusting for confounders. ResultOf 2174 participants, 55% always used LDSS, 27% always used HDSS, and 17% used both LDSS and HDSS. PWID that had injected into their groin during the past month were unlikely to use LDSS, adjusted odds ratio (aOR) 0.14 (95% confidence interval 0.11–0.17), compared to those not using the groin. Those injecting crack were less likely to use LDSS than those not, aOR 0.79 (0.63–0.98). Polydrug use was negatively associated with LDSS use, aOR 0.88 (0.79-0.98) per additional drug. LDSS use was associated with lower prevalent HCV among all PWID (aOR 0.77, [0.64–0.93]), which was stronger among recent initiates (aOR 0.53 [0.30–0.94]) than among experienced PWID (aOR 0.81 [0.66–0.99]). DiscussionPeople who inject into their groin were less likely to use LDSS. Exclusive LDSS use was associated with lower prevalence of HCV amongst PWID that started injecting recently, suggesting LDSS use is protective against HCV.

Options for reducing HIV transmission related to the dead space in needles and syringes

BackgroundWhen shared by people who inject drugs, needles and syringes with different dead space may affect the probability of HIV and hepatitis C virus (HCV) transmission differently.MethodsWe measured dead space in 56 needle and syringe combinations obtained from needle and syringe programs across 17 countries in Europe and Asia. We also calculated the amounts of blood and HIV that would remain in different combinations following injection and rinsing.ResultsSyringe barrel capacities ranged from 0.5 to 20 mL. Needles ranged in length from 8 to 38 mm. The average dead space was 3 μL in low dead space syringes with permanently attached needles, 13 μL in high dead space syringes with low dead space needles, 45 μL in low dead space syringes with high dead space needles, and 99 μL in high dead space syringes with high dead space needles. Among low dead space designs, calculated volumes of blood and HIV viral burden were lowest for low dead space syringes with permanently attached needles and highest for low dead space syringes with high dead space needles.ConclusionThe dead space in different low dead space needle and syringe combinations varied substantially. To reduce HIV transmission related to syringe sharing, needle and syringe programs need to combine this knowledge with the needs of their clients.

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

BackgroundIt 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. MethodsSemi-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. ResultsDecisions 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. ConclusionDetachable 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.

Event-level analyses of sex-risk and injection-risk behaviors among nonmedical prescription opioid users

ABSTRACTBackground: Nonmedical prescription opioid use has been linked to hepatitis C virus (HCV) infection among people who inject drugs and with using high dead space syringes that retain more blood and transfer more HIV if shared. Little is known regarding its effects on sex-risk behaviors. Objectives: This paper examines event-level associations between nonmedical prescription opioid use and sharing high dead space syringes (injection risk) and unprotected intercourse (sex risk) behaviors. Methods: We recruited 1,985 participants from two overlapping risk groups—drug users and men who have sex with men (MSM)—and their sex partners. Participants completed an interview that included event-level sex questions with recent sex partners and injection questions with recent injection partners. We used multivariable generalized estimating equations (GEE) to assess the associations between nonmedical prescription opioid use and unprotected intercourse during sexual encounters and sharing syringes during injection episodes, while adjusting for within-person correlations. Results: When both partners used nonmedical prescription opioids, its use was independently associated with unprotected intercourse in sexual encounters (OR = 2.24; 95% CI = 1.12, 4.49). The use of nonmedical prescription opioids was also associated with sharing high dead space syringes during injection episodes (OR = 6.57; 95% CI = 1.63, 26.51). Conclusion: Nonmedical prescription opioid use is associated with an increase in the risk of unprotected sex and sharing high dead space syringes. HIV and HCV prevention interventions for nonmedical prescription opioid users should address sex-risk behaviors and encourage the use of acceptable low dead space needles and syringes.

Using Pharmacies in a Structural Intervention to Distribute Low Dead Space Syringes to Reduce HIV and HCV Transmission in People Who Inject Drugs.

Ongoing injection drug use contributes to the HIV and HCV epidemics in people who inject drugs. In many places, pharmacies are the primary source of sterile syringes for people who inject drugs; thus, pharmacies provide a viable public health service that reduces blood-borne disease transmission. Replacing the supply of high dead space syringes with low dead space syringes could have far-reaching benefits that include further prevention of disease transmission in people who inject drugs and reductions in dosing inaccuracies, medication errors, and medication waste in patients who use syringes. We explored using pharmacies in a structural intervention to increase the uptake of low dead space syringes as part of a comprehensive strategy to reverse these epidemics.

High dead-space syringe use among people who inject drugs in Tijuana, Mexico

Background: High dead-space syringes (HDSS) are believed to confer an elevated risk of acquiring HIV and other blood-borne infections. Objectives: We identified prevalence and correlates of HDSS use among injection drug users (IDU) in Tijuana, Mexico, where syringe purchase and possession is legal without a prescription. Methods: Beginning in 2011, IDU who reported being 18 years or older and injected drugs within the last month were recruited into a prospective study. At baseline and semi-annually, 557 IDU underwent HIV-testing and interviewer-administered surveys. Logistic regression was used to identify correlates of using HDSS. Results: Of 557 IDU, 40% had ever used HDSS, mostly because no other syringe type was available (72%), or because they were easier to get (20%). Controlling for sex and age at first injection, use of HDSS was associated with cocaine as the first drug injected (Adjusted Odds Ratio [AOR]: 2.68; Confidence Interval 95% [CI]: 1.15–6.22), having been stopped or arrested by police (AOR: 1.84; 95% CI: 1.11–3.07), being deported from the US (AOR: 1.64; 95% CI:1.06–2.53), and believing it is illegal to carry syringes (AOR:1.78; 95% CI: 1.01–3.15). Conclusion: Use of HDSS is surprisingly common among IDU in Tijuana. Efforts are needed to expand coverage of low-dead space syringes through existing syringe exchange programs. Education is required to increase awareness of the harms associated with HDSS, and to inform IDU that syringe possession is legal across Mexico.

Influence of pharmacokinetics on the abuse liability of controlled-release opioid formulations: The case of oxycodone

Influence of pharmacokinetics on the abuse liability of controlled-release opioid formulations: The case of oxycodone

Could low dead-space syringes really reduce HIV transmission to low levels?

Studies published by Zule and colleagues have suggested that use of low dead-space syringes (LDSS) instead of high dead-space syringes (HDSS) by injecting drug users (IDUs) could dramatically reduce HIV transmission. However, evidence is limited because experiments have considered a small range of syringe types and have been unable to reliably estimate the efficacy of using LDSS for reducing HIV transmission. We critically appraise available evidence to determine whether using LDSS is likely to dramatically reduce HIV transmission.We systematically review the literature on the dead-space volume of syringes and estimate the factor difference in blood volume transferred from sharing LDSS or HDSS. Existing data on the relationship between host viral load and HIV transmission risk is used to evaluate the likely efficacy of using LDSS instead of HDSS. An HIV transmission model is used to make conservative impact projections for switching to using LDSS, and explore the implications of heterogeneity in IDU transmission risk and syringe preferences.Although highly variable, reviewed studies suggest that HDSS have on average 10 times the dead-space volume of LDSS and could result in 6/54/489 times more blood being transferred after 0/1/2 water rinses. Assuming a conservative 2-fold increase in HIV transmission risk per 10-fold increase in infected blood inoculum, HDSS use could be associated with a mean 1.7/3.6/6.5-fold increase in transmission risk compared to LDSS for 0/1/2 rinses. However, even for a low efficacy estimate, modelling suggests that partially transferring to LDSS use from using HDSS could dramatically reduce HIV prevalence (generally >33% if LDSS use is 50%), but impact will depend on IDU behavioural heterogeneity and syringe preference.Indirect evidence suggests that encouraging HDSS users to use LDSS could be a powerful HIV prevention strategy. There is an urgent need to evaluate the real life effectiveness of this strategy.

Implementation of low dead-space syringes needs consultation and engagement with drug users

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.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.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.Detachable LDSS are likely to be acceptable and should therefore be offered to those using detachable high dead space syringes and/or fixed 1 ml LDSS syringes to inject into deeper femoral veins. An intervention is needed to support their introduction with ‘training’, ‘education’, ‘persuasion’ and eventual ‘restriction’ components.

Are major reductions in new HIV infections possible with people who inject drugs? The case for low dead-space syringes in highly affected countries

Circumstantial evidence from laboratory studies, mathematical models, ecological studies and bio behavioural surveys, suggests that injection-related HIV epidemics may be averted or reversed if people who inject drugs (PWID) switch from using high dead-space to using low dead-space syringes. In laboratory experiments that simulated the injection process and rinsing with water, low dead space syringes retained 1000 times less blood than high dead space syringes. In mathematical models, switching PWID from high dead space to low dead space syringes prevents or reverses injection-related HIV epidemics. No one knows if such an intervention is feasible or what effect it would have on HIV transmission among PWID. Feasibility studies and randomized controlled trials (RCTs) will be needed to answer these questions definitively, but these studies will be very expensive and take years to complete. Rather than waiting for them to be completed, we argue for an approach similar to that used with needle and syringe programs (NSP), which were promoted and implemented before being tested more rigorously. Before implementation, rapid assessments that involve PWID will need to be conducted to ensure buy-in from PWID and other local stakeholders. This commentary summarizes the existing evidence regarding the protective effects of low dead space syringes and estimates potential impacts on HIV transmission; it describes potential barriers to transitioning PWID from high dead space to low dead space needles and syringes; and it presents strategies for overcoming these barriers.

Abstinence and harm reduction: Can they work together?

Studies published by Zule and colleagues have suggested that use of low dead-space syringes (LDSS) instead of high dead-space syringes (HDSS) by injecting drug users (IDUs) could dramatically reduce HIV transmission. However, evidence is limited because experiments have considered a small range of syringe types and have been unable to reliably estimate the efficacy of using LDSS for reducing HIV transmission. We critically appraise available evidence to determine whether using LDSS is likely to dramatically reduce HIV transmission.We systematically review the literature on the dead-space volume of syringes and estimate the factor difference in blood volume transferred from sharing LDSS or HDSS. Existing data on the relationship between host viral load and HIV transmission risk is used to evaluate the likely efficacy of using LDSS instead of HDSS. An HIV transmission model is used to make conservative impact projections for switching to using LDSS, and explore the implications of heterogeneity in IDU transmission risk and syringe preferences.Although highly variable, reviewed studies suggest that HDSS have on average 10 times the dead-space volume of LDSS and could result in 6/54/489 times more blood being transferred after 0/1/2 water rinses. Assuming a conservative 2-fold increase in HIV transmission risk per 10-fold increase in infected blood inoculum, HDSS use could be associated with a mean 1.7/3.6/6.5-fold increase in transmission risk compared to LDSS for 0/1/2 rinses. However, even for a low efficacy estimate, modelling suggests that partially transferring to LDSS use from using HDSS could dramatically reduce HIV prevalence (generally >33% if LDSS use is 50%), but impact will depend on IDU behavioural heterogeneity and syringe preference.Indirect evidence suggests that encouraging HDSS users to use LDSS could be a powerful HIV prevention strategy. There is an urgent need to evaluate the real life effectiveness of this strategy.

Modeling the effect of high dead‐space syringes on the human immunodeficiency virus (HIV) epidemic among injecting drug users

To illustrate the impact of different proportions of injecting drug users (IDUs) sharing high dead-space syringes (HDSS) or low dead-space syringes (LDSS) on the probability of human immunodeficiency virus (HIV) transmission; and thus the impact on injection-related HIV prevalence and incidence. A stochastic mathematical model was used to evaluate the impact of HDSS use in high- and low-risk IDU populations. Model parameters were obtained from peer-reviewed publications. Analytical solutions of a simplified deterministic model were obtained to explain the effect of HDSS on HIV endemic states. Simulation analysis shows that the HIV epidemic could be sustained even when a small percentage of sharing (10%) involved HDSS. The effect is much stronger in high-risk compared with low-risk populations. Steady state HIV prevalence increases with the proportion of HDSS, and for high- and low-risk populations reaches around 80% and 20%, respectively. For low-risk populations, the use of LDSS could result in the virtual elimination of HIV. These results are dependent upon an evidence-supported assumption of a significant difference in HIV transmission risk associated with HDSS versus LDSS. Our models suggest that injection-related HIV epidemics may not occur when most (e.g. 95% or more) IDUs use LDSS. While these results are based on indirect risk measures and a number of simplifying assumptions, the effect of blood retained in high dead-space syringes on HIV prevalence seems to be very strong, even using relatively conservative assumptions. The findings have potential implications for needle exchange programs and the types of syringes produced and distributed world-wide.

High dead-space syringes and the risk of HIV and HCV infection among injecting drug users

This study examines the association between using and sharing high dead-space syringes (HDSSs)—which retain over 1000 times more blood after rinsing than low dead-space syringes (LDSSs)—and prevalent HIV and hepatitis C virus (HCV) infections among injecting drug users (IDUs). A sample of 851 out-of-treatment IDUs was recruited in Raleigh–Durham, North Carolina, between 2003 and 2005. Participants were tested for HIV and HCV antibodies. Demographic, drug use, and injection practice data were collected via interviews. Data were analyzed using multiple logistic regression analysis. Participants had a mean age of 40 years and 74% are male, 63% are African American, 29% are non-Hispanic white, and 8% are of other race/ethnicity. Overall, 42% of participants had ever used an HDSS and 12% had shared one. HIV prevalence was 5% among IDUs who had never used an HDSS compared with 16% among IDUs who had shared one. The HIV model used a propensity score approach to adjust for differences between IDUs who had used an HDSS and those who had never used one. The HCV models included all potential confounders as covariates. A history of sharing HDSSs was associated with prevalent HIV (odds ratio = 2.50; 95% confidence interval = 1.01, 6.15). Use and sharing of HDSSs were also associated with increased odds of HCV infection. Prospective studies are needed to determine if sharing HDSSs is associated with increased HIV and HCV incidence among IDUs.