People who are cured of or have spontaneously cleared hepatitis C virus (HCV) are at higher risk of reinfection if they are HIV positive or inject drugs. Meanwhile, among injection drug users who have cleared the virus, mental health treatment and opioid substitution therapy (OST) are each associated with a reduced risk of HCV reinfection.
Publishing their findings in The Lancet, researchers analyzed data from the British Columbia Hepatitis Testers Cohort, which includes information on all individuals tested for HCV or HIV at the British Columbia Centre for Disease Control Public Health Laboratory between 1990 and 2013.
The study included 5,915 people who cleared hep C, 3,690 of them spontaneously (meaning without medical intervention) and 2,225 through an HCV-treatment cure. A total of 452 of the overall cohort (8 percent) were subsequently reinfected with hep C, including 402 of them (11 percent) from the spontaneous clearance group and 50 (2 percent) from the group cured through treatment.
The overall cohort was followed for a cumulative 35,672 years and a median 5.4 years. The median time between clearing the virus and reinfection was 3 years. This translated to an overall reinfection rate of 1.27 percent of the cohort per year of follow-up.
The reinfection rate was 1.59 percent per year of follow-up in the spontaneous clearance group and 0.48 percent in the group cured through treatment. After adjusting the data for various factors, the study authors found that spontaneous clearance was associated with a 171 percent increased likelihood of reinfection compared with having a treatment-based cure. Having HIV was linked to a 125 percent increased likelihood of reinfection compared with not having HIV. And injecting drugs was linked to a 53 percent increased likelihood of reinfection compared with not injecting drugs.
Looking at the 1,604 members of the overall cohort who reported current injection drug use, the researchers found that receiving OST was associated with a 27 percent reduced likelihood of reinfection while receiving mental health counseling services was associated with a 29 percent reduction in risk.
The researchers concluded that OST and mental health counseling among injection drug users who clear HCV could reduce their risk of reinfection.
To read a press release about the study, click here.
To read the study abstract, click here.