The increase in acute hepatitis C virus (HCV) infections relates directly to the growing opioid epidemic and increases in injection drug use, according to a new study.
“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,” stated researchers led by Jon E. Zibbell, PhD, of the Behavioral and Urban Health Program, RTI International, Atlanta, GA.
The researchers published their results in February 2018 American Journal of Public Health.
The study examined cases of acute HCV infection reported by US states from 2004 to 2014 in conjunction with an analysis for the same time period of national substance use disorder admissions data from the Substance Abuse and Mental Health Services Administration’s (SAMHSA’s) Treatment Episode Data Set–Admissions for trends in:
• Any opioid injection
• Heroin injection
• Prescription opioid analgesics injection
• Other non-opioid drug injection
The results show the annual incidence rate of acute HCV infection increased more than 2-fold from 0.3 cases per 100,000 to 0.7 cases per 100 000, with significant increases among select demographic subgroups. Injection drug use was the most frequently cited risk factor. More than 80% of acute case reports with an identified HCV-related risk indicated injection drug use in 2014.
“These increases indicate a striking demographic convergence among opioid use or misuse, injection drug use, and acute HCV infection,” the researchers stated.
In addition, 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.
The concurrent increase in cases of acute HCV infection and substance use disorder treatment admissions attributed to prescription opioid analgesics may be explained by the higher risk for HCV infection for those who inject opioids than for those who inject heroin and non-opioid drugs. “Our findings, which reveal national increases in both the number of persons injecting prescription opioid analgesics and the number of acute HCV infections, indicate a more widespread problem than previous studies have shown,” the researchers stated.
They also noted a concerning demographic shift in persons affected by acute HCV infection toward Hispanics. A finding not previously identified at the national level was the significant increase (429%) in both acute HCV infections and treatment admissions attributed to prescription opioid analgesics injection among Hispanics from 2004 to 2014.
“Substantial increases in the number of persons with opioid use disorders who inject drugs have the potential to thwart the nation’s efforts to control morbidity and mortality associated with HCV infection,” the researchers stated. “Integrated health services that include syringe service programs, medication-assisted treatment, and comprehensive HCV testing and linkage to care and treatment of HCV-infected PWID are essential to reduce prevalence and incidence among the population.”
They also noted that increasing access to curative HCV treatment, such as direct-acting antiviral agents, is a key component of a comprehensive program.