摘要：Objectives. To compare US trends in rates of injection drug use (IDU), specifically opioid injection, with national trends in the incidence of acute HCV infection to assess whether these events correlated over time. Methods. We calculated the annual incidence rate and demographic and risk characteristics of reported cases of acute HCV infection using surveillance data from 2004 to 2014 and the annual percentage of admissions to substance use disorder treatment facilities reporting IDU for the same time period by type of drug injected and demographic characteristics. We then tested for trends. Results. The annual incidence rate of acute HCV infection increased more than 2-fold (from 0.3 to 0.7 cases/100 000) from 2004 to 2014, with significant increases among select demographic subgroups. Admissions for substance use disorder attributed to injection of heroin and prescription opioid analgesics increased significantly, with an almost 4-fold increase in prescription opioid analgesic injection. Significant increases in opioid injection mirrored those for reported cases of acute HCV infection among demographic subgroups. Conclusions. These findings strongly suggest that the national increase in acute HCV infection is related to the country’s opioid epidemic and associated increases in IDU. Hepatitis C virus infection is the most common chronic blood-borne infection in the United States and a substantial cause of morbidity and mortality. 1 Injection drug use (IDU) is the primary risk factor for HCV transmission and the leading cause of incidence in the United States. 2 HCV infection can occur rapidly after IDU initiation: A meta-analysis examining the time from onset of injection to incidence of HCV infection found a cumulative incidence of 28% (95% confidence interval = 17%, 42%) at 1 year of drug injection. 3 Consequently, once the virus is introduced into a network of persons who inject drugs (PWID), it can circulate quickly through the reuse of contaminated drug injection equipment—specifically, needles, syringes, cookers, and filters. 4,5 Other factors associated with increased risk for HCV infection include having a high injection frequency, 6 using high dead-space syringes, 7 and injecting prescription opioid analgesics (POAs). 8,9 The demographic characteristics and behavioral risk factors associated with the increase in cases of acute HCV infection correspond to the populations and behaviors that characterize the nation’s opioid epidemic. State surveillance data indicate a nationwide increase in reported cases of acute HCV infection since 2004, with the largest increases occurring east of the Mississippi River and exceptionally high concentrations in central Appalachia. 10 Findings from an analysis of data of 4 central Appalachian states from 2006 to 2012 showed that 45% of the increases in acute cases of HCV infection were among young persons (aged ≤ 30 years), with nearly three-quarters (196/265) of persons who reported a risk factor citing IDU. 11 Over the same time period, these 4 states also experienced a significant increase in the proportion of young persons admitted to substance use disorder (SUD) treatment who reported injecting opioids, including heroin and POAs. Similar increases in IDU and HCV infection have been documented in Massachusetts, 12 Wisconsin, 13 and New York, 14 and most recently a major HIV outbreak in southeastern Indiana was facilitated by the injection of the prescription opioid oxymorphone, with 92% of persons newly identified with HIV coinfected with HCV. 15 Overall, these reports suggest that national increases in acute HCV infections are being fueled by the nation’s opioid epidemic. To improve our understanding of the relationship between the epidemics of acute HCV infection and opioid use and misuse, we extend our previous 4-state analysis of central Appalachia 11 to the country as a whole. In this work, we examine cases of acute HCV infection reported by US states from 2004 to 2014 in conjunction with analyzing national SUD admissions data from the Substance Abuse and Mental Health Services Administration’s (SAMHSA’s) Treatment Episode Data Set–Admissions (TEDS) for trends in any opioid injection, heroin injection, POA injection, and other (i.e., nonopioid drug) injection for the same time period. We expected to find concurrent increases in SUD treatment admissions among persons with opioid use disorders who inject drugs and acute HCV infections on a national scale, echoing the dual epidemics previously identified in Appalachia.
