METHODS: Collation and review of existing estimates of IDU prevalence and HIV prevalence from published and unpublished documents for the period 1998-2003. The strength of evidence for the information was assessed based on the source and type of study.
RESULTS: Estimates of IDU prevalence were available for 130 countries. The number of IDU worldwide was estimated as approximately 13.2 million. Over ten million (78%) live in developing and transitional countries (Eastern Europe and Central Asia, 3.1 million; South and South-east Asia, 3.3 million; East-Asia and Pacific, 2.3 million). Estimates of HIV prevalence were available for 78 countries. HIV prevalence among IDU of over 20% was reported for at least one site in 25 countries and territories: Belarus, Estonia, Kazakhstan, Russia, Ukraine, Italy, Netherlands, Portugal, Serbia and Montenegro, Spain, Libya, India, Indonesia, Malaysia, Myanmar, Nepal, Thailand, Viet Nam, China, Argentina, Brazil, Uruguay, Puerto Rico, USA and Canada.
CONCLUSIONS: These findings update previous assessments of the number of countries with IDU and HIV-infected IDU, and the previous quantitative global estimates of the prevalence of IDU. However, gaps remain in the information and the strength of the evidence often was weak.
RESULTS: Women and girls comprise one-third of people who use and inject drugs globally. There is substantial variation in HIV prevalence in this population, between and within countries. There is a pronounced lack of data examining HIV risk among particularly vulnerable subpopulations of women who use and inject drugs, including women who have sex with women, transgender women, racial and ethnic minority women, and young women. Women who use and inject drugs experience stigma and discrimination that affect access to services, and high levels of sexual risk exposures.
CONCLUSIONS: There are significant gaps in our understanding of the epidemiology of drug use and injecting among women and girls and HIV risk and prevalence in this population. Women are frequently underrepresented in studies of drug use and HIV risk and prevalence among people who inject drugs, limiting our understanding of possible sex differences in this population. Most research originates from developed countries and may not be generalizable to other settings. A great deal of work is needed to improve understanding of HIV among particularly vulnerable subpopulations, such as transgender women who use drugs. Better data are critical to efforts to advocate for the needs of women and girls who use and inject drugs.
DESIGN: Systematic review and meta-analysis.
SETTING: Primary care setting.
PARTICIPANTS: Of 1568 studies screened, 14 studies with 7035 PWID were included.
MEASURES: PubMed, Embase, Web of Sciences, CENTRAL and Cochrane review databases were searched without language restriction from their inception to 27 January 2016. All published study designs with control groups that reported the effectiveness of pharmacy-based NSP on outcomes of interest were included. Outcomes of interest are risk behaviour (RB), HIV/hepatitis C virus (HCV) prevalence and economic outcomes. The estimates of pooled effects of these outcomes were calculated as pooled odds ratio (OR) with 95% confidence interval (CI) using a random-effects model. Heterogeneity was assessed by I2 and χ2 tests.
FINDINGS: Most studies (nine of 14, 64.3%) were rated as having a serious risk of bias, while 28.6 and 7.1% were rated as having a moderate risk and low risk of bias, respectively. For sharing-syringe behaviour, pharmacy-based NSPs were significantly better than no NSPs for both main (OR = 0.50, 95% CI = 0.34-0.73; I2 = 59.6%) and sensitivity analyses, excluding studies with a serious risk of bias (OR = 0.52, 95% CI = 0.32-0.84; I2 = 41.4%). For safe syringe disposal and HIV/HCV prevalence, the evidence for pharmacy-based NSPs compared with other NSP or no NSP was unclear, as few of the studies reported this and most of them had a serious risk of bias. Compared with the total life-time cost of US$55 640 for treating a person with HIV infection, the HIV prevalence among PWID has to be at least 0.8% (for pharmacy-based NSPs) or 2.1% (for other NSPs) to result in cost-savings.
CONCLUSIONS: Pharmacy-based needle/syringe exchange programmes appear to be effective for reducing risk behaviours among people who inject drugs, although their effect on HIV/HCV prevalence and economic outcomes is unclear.
METHODS: We developed a linear optimisation model to estimate efficiency gains that could be achieved based on current procurement of OAT. We also developed a dynamic, compartmental population model of HIV transmission that included both injection and sexual risk to estimate the effect of OAT scale-up on HIV infections and mortality over a 10-year horizon. The compartmental population model was calibrated to HIV prevalence and incidence among PWID for 23 administrative regions of Ukraine. Sources for regional data included the SyrEx database, the Integrated Biological and Behavioral Survey, the Ukrainian Center for Socially Dangerous Disease Control of the Ministry of Health of Ukraine, the Public Health Center of the Ministry of Health of Ukraine, and the Ukrainian Census.
FINDINGS: Under a status-quo scenario (OAT coverage of 2·7% among PWID), the number of new HIV infections among PWID in Ukraine over the next 10 years was projected to increase to 58 820 (95% CI 47 968-65 535), with striking regional differences. With optimum allocation of OAT without additional increases in procurement, OAT coverage could increase from 2·7% to 3·3% by increasing OAT doses to ensure higher retention levels. OAT scale-up to 10% and 20% over 10 years would, respectively, prevent 4368 (95% CI 3134-5243) and 10 864 (7787-13 038) new HIV infections and reduce deaths by 7096 (95% CI 5078-9160) and 17 863 (12 828-23 062), relative to the status quo. OAT expansion to 20% in five regions of Ukraine with the highest HIV burden would account for 56% of new HIV infections and 49% of deaths prevented over 10 years.
INTERPRETATION: To optimise HIV prevention and treatment goals in Ukraine, OAT must be substantially scaled up in all regions. Increased medication procurement is needed, combined with optimisation of OAT dosing. Restricting OAT scale-up to some regions of Ukraine could benefit many PWID, but the regions most affected are not necessarily those with the highest HIV burden.
FUNDING: National Institute on Drug Abuse.