HCV Screening Should Not Just Focus on At-Risk Populations

At the Conference on Retroviruses and Opportunistic Infections (CROI 2017) in Seattle, Washington, researchers from MedStar Health Research Institute in Maryland presented new data on hepatitis C virus (HCV)-positive non-baby boomers.

It’s widely acknowledged that those individuals belonging to the baby boomer age group (those born between 1946 and 1964) are at higher risk of acquiring HCV infection. According to the Centers for Disease Control and Prevention (CDC), these individuals are five times more likely to be infected with HCV. However, other at-risk populations may not be getting adequately tested for the virus.

Baby boomers are at a higher risk for HCV, but the reason why isn’t completely understood. Some researchers say that HCV transmission was highest from the 1960s to 1980s; others attribute it more to the fact that this group was exposed to infected medical equipment before sufficient transmission precautions were put into place. This is why the CDC recommends that all people in this population get tested for HCV, even if they don’t have any other risk factors. Beyond baby boomers, those who have ever injected drugs and those who received a blood transfusion or organ donation before 1992 are also advised to get tested.

The study presented at CROI2017 examined 329 non-baby boomers tested between July 1, 2015 and June 30, 2016. The case-control analysis did not match controls for age, sex, or race—although clinical studies typically do—because the researchers wanted to observe potential differences.

Of the study participants, 80 (1.7%) were HCV antibody positive (Ab+) or indeterminate, compared to the 249 HCV antibody negative (Ab-) controls.

Baseline characteristics for the 329 participants differed based on whether they were Ab+ or Ab-: respectively, the results showed that about 55.8% and 45% were female, 48.2% and 36.3% were African American, and 69.1% and 46.3% held private insurance. The average age differed depending on whether or not the participants were in the “baby boomer” age group—around 36 years and 75 years between the two antibody groups.

Risk factors that could contribute to HCV infections were documented among the participants. For the Ab+ and Ab- groups, participants had opiate prescriptions (40% and 20.1%), elevated liver function tests (17.5% and 14.5%), drug use (35% and 1.6%), high sexual behavior (6.3% and 16.9%), renal disease (2.5% and 2%), sexually transmitted infections (10% and 10%), and HIV (5% and 2.8%). One participant had a blood transfusion (Ab+), two had cirrhosis (Ab+), and three had alcohol abuse (two Ab+, one Ab-).

About 50% of those participants in the age clusters of 46 to 50 and 71 to 75 tested positive.

The researchers explained, “There was a significant interaction for age and opiate prescription use with those over 40 with an opiate prescribed 11x more likely to be hepatitis C Ab+.” Participants were also more likely to be HCV Ab+ if they had drug use, Medicaid (over private insurance), and were Caucasian (over any other race).

Previous research has found that drug use is a strong indicator of HCV-positive status, and this recent study backs that up. However, the researchers found that more non-baby boomers with HCV are Caucasian than African American—which is the opposite among baby boomers.

A total of 18 HCV Ab+ (23%) and 123 HCV Ab- (49%) participants did not have any risk factors indicated in the study.

The authors concluded, “Testing non-[baby boomer] patients only on the basis of risk factors has the potential to miss a significant number of hepatitis C Ab+ patients.”