African Americans face a “triple whammy” when it comes to the hepatitis C virus, a new study finds.
Two aspects of this triple threat are well known: the high prevalence of the virus in the African-American community and the lower response to therapy of infected individuals, according to Zobair Younossi, MD, of Inova Fairfax Hospital in Fairfax, Va.
But there’s a third threat: African Americans don’t spontaneously clear the virus as often as other racial and ethnic groups, Younossi reported at the annual meeting of the American Association for the Study of Liver Diseases.
“I would call it a triple whammy — high prevalence, lower chance of spontaneous clearance, and then the lower chance of sustained virologic response,” said Younossi.
“This is the population that we really need to focus on and develop something that will help,” he said during a poster presentation.
Younossi and colleagues analyzed data collected from 2005 to 2008 by the National Health and Nutrition Examination Survey (NHANES), which included clinical and laboratory data on nearly 15,000 participants.
Included in the data were results for tests for hepatitis C antibodies and RNA, Younossi said, which allowed the researchers to look at rates of spontaneous clearance of the virus.
All told, they found that 192 of the 14,750 participants had antibodies to the virus. Also, 149 of the participants had hepatitis C RNA, indicating they remained infected. The other 43 had cleared the virus naturally.
In a univariate analysis, the only factor that was significantly different between the groups was the proportion of African Americans who remained infected versus those who had cleared the virus (P=0.0163), Younossi said.
The rate of clearance among African Americans in the cohort was 9.25%, compared with 27.2% among Caucasians and 31.2% among Hispanics.
In a multivariate analysis, Younossi said, the only independent predictor of not being able to clear the virus was African-American race. The odds ratio for non-clearance for African Americans, compared with Caucasians, was 3.80, with a 95% confidence interval from 1.31 to 11.36, which was significant at P=0.015.
The finding is, “not unexpected,” according to Gary Davis, MD, of Baylor College of Medicine in Houston, who was not involved in the study.
So how do you know if you have it? Here’s how to find out:
HCV Antibody Testing: Diagnosing hepatitis C begins with an antibody test. Antibodies to HCV can be detected in the blood, usually within two or three months after the virus enters the body. If a person is positive for HCV antibodies, he or she has been exposed to the virus in the past. About 15 to 25 percent of people who are initially infected with HCV are able to clear the virus from their bodies, usually within six months of exposure, so the next step is to look for the actual virus in the bloodstream, using a viral load test. If a person has an acute infection, meaning that he or she was recently infected with HCV, antibodies may not have formed yet, so a viral load is necessary to confirm infection.
HCV Viral Load Testing: A health care provider can request a qualitative HCV RNA test to determine if the virus is in a person’s bloodstream. A medical provider can also order a quantitative HCV RNA test to figure out a person’s HCV viral load (the amount of HCV in a measurement of blood). Various methods are used to detect HCV RNA, including TMA (transcription-mediated amplification), PCR (polymerase chain reaction), and bDNA (branched DNA). Qualitative viral load testing tends to be more sensitive than quantitative testing. Viral load testing using PCR or TMA are more sensitive than bDNA testing.
The HCV viral load is an important laboratory test. Though the HCV viral load test cannot determine if or when someone with hepatitis C will develop cirrhosis or liver failure, it can help determine the length of treatment needed. HCV viral load testing is also used during treatment to determine how well it is working.
For more information, visit the BDO Hepatitis C Channel.