People Who Inject Drugs (PWID)

"This report describes data from 11,437 PWID who participated in NHBS in 2018, of whom 69% identified as male, 30% female, and 1% transgender; 39% were white, 33% were black, and 21% were Hispanic or Latino; 36% were aged ≥50 years (Table 1). Among all participants, 26% had no health insurance, 21% had not visited a health care provider, and the household income of 75% of participants was at or below the federal poverty level.

"In 2018, 6% of participants with a valid NHBS HIV test result tested positive for HIV (Table 2). By gender, HIV prevalence was as follows: 6% among males, 6% among females, and 28% among transgender. By race and ethnicity, HIV prevalence was as follows: 9% among blacks, 8% among Hispanics or Latinos, and 4% among whites.

"CDC recommends that persons at increased risk of HIV infection, including PWID, undergo HIV testing at least annually [10]. Among participants who did not report a previous HIV-positive test result or who had received their first HIV-positive test result less than 12 months before the interview, 55% reported that they had been tested for HIV in the 12 months before the interview, and 90% reported that they had ever been tested (Table 3).

"Among participants who reported being tested for HIV in the 12 months before the interview, 66% reported their most recent test was performed in a clinical setting while 29% reported being tested in a nonclinical setting, such as an HIV counseling and testing site, an HIV street outreach program or mobile unit, a SSP, or at home (Table 4)."

"Globally, there are nearly 15.6 million people (aged 15–64) who inject drugs (PWID), with an estimated 2.6 million PWID in North America (Degenhardt et al., 2017). Canada and the United States (US) have both seen significant increases in the rate of injection drug use, as well as a rise in the rate of infections and fatal overdose related to injection drug use (Jacka et al., 2020; Levitt et al., 2020). The risk of fatal overdose significantly increases when people inject drugs alone, and may be prevented with timely intervention (i.e. administration of naloxone, an overdose prevention medication) (Colledge et al., 2019). There is also an increased risk of disease transmission (e.g. HIV, hepatitis) and serious infections associated with injecting drugs, which are often related to using unsterile equipment, injecting in unhygienic settings, or rushed injections (Colledge et al., 2019). The increase in injection drug use and the risks associated with using alone, in unhygienic or unsupervised settings necessitate the need for services that support safe injection practices among PWID."

"People who use heroin (PWUH) have increased morbidity and mortality compared to the general population [1]. A syndemic of opioid overdose, human immunodeficiency virus (HIV), hepatitis C virus (HCV), skin and soft tissue infections (SSTI), and infective endocarditis accounts for many of the poor health outcomes among PWUH [2,3,4,5]. Heroin can be consumed in several ways, including injection and smoking [6]. High-risk injection behaviors, including syringe sharing and reuse of non-sterile injection equipment, are established routes of HIV and HCV transmission and increase risk of SSTI and infective endocarditis [7,8,9]. Opioid overdose is a common cause of mortality among PWUH, with higher overdose risk among those who inject [10,11,12].

"Because smoking heroin does not injure the skin or introduce non-sterile equipment into blood or tissue, this method of consumption does not entail the same risk of blood-borne infections or SSTI compared to injection. While similar pharmacological effects can be achieved by smoking or injecting heroin, peak plasma concentrations are 2–4 times lower when heroin is smoked, which may reduce risk of lethal opioid overdose [13, 14]. Programs that encourage PWUH to transition from injecting to smoking heroin may decrease injection frequency and thereby reduce harms associated with heroin use, including risks of infection and overdose [15]. Distribution of smoking equipment may also help PWUH avoid using pipes fashioned from cans or other poor-quality materials that easily crack or overheat, thereby reducing risk of developing burns or cuts on the lips that can serve as sites of infection [16,17,18]. Pipe distribution programs may also reduce pipe sharing, a risk behavior potentially associated with respiratory virus or HCV transmission [17,18,19,20]."

"In this pilot pretest–posttest quasi-experimental study, we saw a lower proportion of SSP clients exclusively inject heroin and a higher proportion of SSP clients consume heroin through both injection and smoking after the implementation of a heroin pipe distribution program. The proportion of SSP clients who reported syringe reuse was also lower following the heroin pipe distribution intervention. We did not observe any difference in self-reported health outcomes associated with drug use between the pre- and post-intervention periods; however, the short follow-up period and small sample size of this pilot study may have contributed to this null finding. Our results suggest heroin pipe distribution may be a novel RTI that can be added to existing SSPs to further reduce harms associated with heroin use. This study also highlights the potential for public health service innovations to be developed by marginalized communities and the importance of placing PWUD in leadership positions in efforts to optimize harm reduction programming.

"Despite the non-randomized design of this pilot study, several findings suggest heroin pipe distribution may have prompted changes in heroin consumption behaviors among PWUH. The proportion of SSP clients who exclusively injected heroin was lower by a quarter, while the proportion who both injected and smoked heroin was higher by over a quarter after heroin pipe distribution began. Twenty-four percent of respondents who used heroin reported heroin pipe distribution had reduced their heroin injection. Higher proportions of SSP clients who received heroin pipes exclusively smoked heroin or both smoked and injected heroin compared to SSP clients who did not receive a heroin pipe. We are unaware of any prior published research investigating heroin pipes as an RTI; however, pre–post-analyses examining foil distribution at SSPs in Europe found similar changes in drug consumption behaviors, with up to 85% of SSP clients having used foil to inhale rather than inject heroin on at least one occasion [23, 28]. Our non-randomized study design cannot control for confounding and prevents firm conclusions as to whether this observed shift from injection to smoking can be attributed to the intervention. Additionally, only 14% of respondents who used heroin completed surveys during both the pre- and post-intervention periods, and thus, outcomes may have been impacted by changes in the SSP client population across time periods. Further experimental research is needed to clarify the causal relationship between heroin pipe distribution and reductions in heroin injection. Study designs that are randomized by individual may be complicated by heroin pipe sharing across intervention and control groups. Cluster randomization may better control for contamination given extensive social networks and resource exchange among PWUD [29]."

"There are an estimated 15.6 million people who inject drugs (PWID) globally (3.2 million women and 12.5 million men). Among these persons, an estimated 17.8% are living with HIV, 52.3% are Hepatitis C (HCV)-antibody positive, and 9.1% are Hepatitis B (HBV) surface antigen positive [1]. PWID are also at high risk for skin and soft tissue infections and infective endocarditis [2–5]. In addition, injection drug use increases risks for fatal and nonfatal overdose [6–9]. Global estimates suggest that 82.9% of PWID primarily inject opioids, underscoring the urgency of implementing evidence-based response strategies to mitigate the range of adverse consequences associated with the opioid crisis [1]."

"Importantly, our results show that evidence of injection was more prevalent among decedents with xylazine and heroin and/or fentanyl detections. Despite limited literature on the health effects of chronic xylazine use, regular injection of xylazine has been associated with skin ulcers, abscesses and lesions in Puerto Rico.^{2 3} Semistructured interviews with people who use xylazine in Puerto Rico revealed that regular use of xylazine leads to skin ulcers.⁴ As skin ulcers are painful, people may continually inject at the site of the ulcer to alleviate the pain as xylazine is a potent α2-adrenergic agonist that mediates via central α2-receptors, which decreases perception of painful stimuli.¹ People may self-treat the wound by draining or lancing it, which can exacerbate negative outcomes.⁸ While Philadelphia has seen a rise in skin and soft tissue infections relating to injection drug use, it is not yet clear whether or not this is due to increased presence of xylazine in the drug supply.⁹"

"Canada is in the midst of a devastating overdose crisis that has been further exacerbated by the COVID-19 pandemic and, in particular, the subsequent increased toxicity of the drug supply [1]. Between January 2016 and June 2022, close to 33,000 people died from an overdose in Canada, with the provinces of British Columbia, Ontario, and Alberta accounting for 88% of those deaths [2]. Fentanyl, and to a lesser extent fentanyl analogues, have contributed to a sharp rise in the toxicity of the unregulated drug supply and fatal overdoses [2]. Between January and June 2022, fentanyl was detected in 76% of overdose deaths in Canada [2]. In Ontario, fentanyl is involved in 88% of fatal overdoses [3]. In Toronto, this number rises to 93% [3]."

"UNODC, UNAIDS, WHO and the World Bank jointly estimate that some 11.2 million persons worldwide injected drugs in 2020. There has been no measurable change in the estimated global prevalence of injecting drug use from the previous estimate for 2019, which was also 0.22 per cent of the population aged 15–64. However, any trend data must be viewed with caution as the methodologies used to produce national or subnational PWID population size estimations may have changed.

"Approximately 59 per cent of PWID worldwide reside in East and South-East Asia, Eastern Europe and North America. Injecting drug use remains particularly prevalent in Eastern Europe and, to a lesser extent, Central Asia and Transcaucasia, and North America, with rates that are 5.8, 2.6 and 2.5 times the global average, respectively."

"Safer supply programs are not designed or implemented with the explicit goal of changing injection practices. However, the experiences of clients and providers help us understand how a structural intervention, such as safer supply, can impact other aspects of IDU (e.g., frequency of injection) and its associated health risks (e.g., HIV, HCV, etc.). As Perlman and Jordan [37] point out, structural interventions are important because “structural factors contribute potently to creating the context that renders individuals and areas vulnerable to the syndemic of [overdose, HCV, and HIV]” (p.109). These interventions work upstream, to change the “risk environment” [38, 39], rather than solely focusing on mitigating the downstream consequences at the level of the individual. Our study findings suggest that changing the “risk environment,” by providing an alternative to the toxic drug supply, creates more opportunities for risk reduction. Changes in injection practices identified in this analysis offer a compelling example.

"Our findings suggest that clients enrolled in safer supply programs changed their injection practices in three intersecting ways: (1) they changed how often they injected, (2) they changed what they injected, and (3) they changed their mode of consumption (from injecting to swallowing or snorting). These findings add to existing research [16,17,18] by providing a more dynamic understanding of injection practices in the context of safer supply programs and further supporting the idea that safer supply can contribute to reducing injection-related health risks in addition to overdose risks [40]. We posit that safer supply programs have the potential to address disease prevention and health promotion gaps that other stand-alone downstream harm reduction interventions (e.g., needle and syringe programs) cannot address, by working upstream and providing a safer alternative to fentanyl. As Rhodes [38] reminds us, harm reduction interventions such as needle and syringe exchange programs are crucial, but their effectiveness at preventing injection-related health risks can be undermined by a particular “risk environment.” For example, if a particular shift in the drug supply results in people injecting more frequently, such is the case with fentanyl, an HIV outbreakFootnote1 could occur even in jurisdictions where needle and syringe exchange programs are available [38].

"It is important to note, however, that not all changes in injection practices could be attributed directly to safer supply programs. We identified several indirect factors, such as poor venous access and having to inject hydromorphone tablets not intended for intravenous administration (for more on this, see study by Ivsins and colleages [17] and guidance by the British Columbia Centre on Substance Use [42]), which shaped the decision to stop injecting. Having the option of taking safer supply medications orally made this decision possible, but it is unclear if all clients who stopped injecting would have done so if they had access to a range of injectable safer supply medications and/or had better venous access. Moreover, it is unclear to what extent clients continued to inject because the safer supply medications dosage/potency was not meeting their needs, as suggested by clients who spoke of the need to supplement with fentanyl, and/or because they wanted to continue injecting. Future research should aim at exploring these nuances because safer supply programs are not intended as interventions to stop clients from injecting. If clients want to inject, they should be able to do so and access injectable safer supply medications (including injectable hydromorphone) as well as sterile supplies and supervised safer consumption services—a priority echoed in a recent report on substance use patterns and safer supply preferences of PWUD in British Colombia [43]."

"Overall, the number of PWID per 10,000 persons aged 15–64 years varied from 31 to 345 across MSAs [Metropolitan Statistical Areas], median 104.4 (mean 127.4; standard deviation 66.7; percentile range 76–162) in 1992 and from 34 to 324 across MSAs, median 91.5 (mean 103.6; standard deviation 56.4; percentile range 61–125 ) in 2007 indicating an overall decline in PWID prevalence across MSAs.

"Figure 5 shows the overall trajectory of the PWID prevalence rates based on the multilevel model. Trend analysis of the overall results is consistent with a decline in the early study period, followed by an increase in 2000–02, and then remaining stable thereafter over time. On average there has been very little change since 2002 (mean 105.0) to 2007 (mean 103.6). Overall, across the 96 MSAs the mean PWID prevalence mostly decreased during our study period, as did the dispersion of estimates over time."