Estimated Number of People Who Inject Drugs in the United States

Abstract

Background Public health data signal increases in the number of people who inject drugs (PWID) in the United States during the past decade. An updated PWID population size estimate is critical for informing interventions and policies aiming to reduce injection-associated infections and overdose, as well as to provide a baseline for assessments of pandemic-related changes in injection drug use. Methods We used a modified multiplier approach to estimate the number of adults who injected drugs in the United States in 2018. We deduced the estimated number of non-fatal overdose events among PWID from two of our previously published estimates: the number of injection-involved overdose deaths and the meta-analyzed ratio of non-fatal to fatal overdose. The number of non-fatal overdose events was divided by prevalence of non-fatal overdose among current PWID for a population size estimate. Results There were an estimated 3,694,500 (95% CI: 1,872,700–7,273,300) PWID in the U.S. in 2018, representing 1.46% (95% CI: 0.74% – 2.87%) of the adult population. The estimated prevalence of injection drug use was highest among male persons (2.1%; 95% CI: 1.1–4.2%), non-Hispanic White persons (1.8%; 95% CI: 0.9–3.6%), and adults aged 18–39 years (1.8%; 0.9–3.6%). Conclusions Using transparent, replicable methods and largely publicly available data, we provide the first update to the number of people who inject drugs in the U.S. in nearly ten years. Findings suggest the population size of PWID has substantially grown in the past decade and that prevention services for PWID should be proportionally increased.

Integrated Infectious Disease and Substance Use Disorder Care for the Treatment of Injection Drug Use–Associated Infections: A Prospective Cohort Study With Historical Control

“…We observed secondary improvements in SUD care engagement and antibiotic completion as well as decreased rates of PDD. Between 2011 and 2018, the estimated number of PWID in the US increased by 5-fold to 3.7 million people [ 27 ]. The consequence of this trend is demonstrated by surging rates of drug overdose deaths [ 2 ].…”

Maternal hepatitis C prevalence and trends by county, US: 2016–2020

“…In addition, some of the bias analyses suggested downward trends in maternal hepatitis C prevalence, which is incongruous with the recent syndemics of hepatitis C infection, injection drug use and drug overdose deaths in the US. [21][22][23] In the absence of nationally representative data on trends and differences in the degree of misclassification, these sensitivity analyses were considered exploratory, as it is unknown how misclassification has truly changed over time and by urban-rural category.…”

“…Third, the misclassification bias analyses were based on available HCV infection sensitivity data from select states and examined several plausible misclassification scenarios, finding that estimated trends were heavily influenced by the magnitude of the assumed differences in misclassification over time and by urban–rural category. In addition, some of the bias analyses suggested downward trends in maternal hepatitis C prevalence, which is incongruous with the recent syndemics of hepatitis C infection, injection drug use and drug overdose deaths in the US 21–23 …”

“We want everything in a one-stop shop”: acceptability and feasibility of PrEP and buprenorphine implementation with mobile syringe services for Black people who inject drugs

“…While HIV incidence decreased among PWID between 2004 and 2015, the recent surge in HIV outbreaks associated with IDU has destabilized our progress toward EHE targets for this high-priority community, particularly Black PWID, who comprise 27% of new HIV diagnoses due to IDU [ 1 – 5 , 7 , 13 ]. The increasing frequency of outbreaks has been fueled by the convergence of the opioid and stimulant use disorder crises in the US [ 14 – 19 ], which has led to significantly more people injecting drugs than ever before [ 20 ]. With over 108,000 people losing their lives to preventable overdose in 2021 [ 21 ], comprehensive HIV prevention has become progressively more complicated.…”

“…Recent meta-analyses indicate that buprenorphine decreases the risk of all-cause mortality for people with OUD by approximately 50% [ 47 ]. However, despite increases in the number of people in the US receiving buprenorphine in recent years, numerous studies indicate significant racial/ethnic disparities in buprenorphine treatment access [ 20 , 43 , 48 – 53 ]; Black patients with OUD are 77% less likely to receive buprenorphine prescriptions compared with White patients [ 43 ] as the result of structural racism within the healthcare system.…”