May 9, 2011 -- Screening all people born between 1946 and 1970 for the hepatitis C virus would greatly reduce the number of people with advanced liver disease linked with the virus, according to new research.
''Current recommendations are to screen high-risk people," says researcher Lisa McGarry, MPH, director of health economics and outcomes research at Ingenix Life Sciences, a health information, technology, and consulting service.
Intravenous drug users are considered at high risk.
McGarry and her colleagues suggest that all people in the age group known as baby boomers, along with those born a few years after, be screened.
McGarry presented her research yesterday at Digestive Disease Week in Chicago.
Otther experts who reviewed the research say the model is not enough information to suggest a change in the recommendation for hepatitis C testing.
Hepatitis C Testing: The Disease Model
Using a computerized model of disease progression, the researchers projected the outcomes for the age-based screening they propose.
They chose the baby boomer population as well as those born a few years after because the hepatitis C infection rate is particularly high among them. According to the researchers, about 1.6 million people in the U.S. aged 40 to 64 are infected but do not know it.
The virus is spread primarily through contact with the blood of an infected person, according to the CDC. Most people become infected by sharing needles or other equipment used to inject IV drugs.
People who got a blood transfusion before 1992, when screening of the blood supply became available, are also at risk. Less often, people become infected when sharing personal care items such as toothbrushes or razors that have been in contact with an infected person's blood. Infection can occur after having sex with an infected person, but that risk is considered low. The risk becomes greater if a person has multiple sex partners, rough sex, an STD, or HIV.
Health care workers who have needlestick injuries when caring for an infected person can also become infected.
Using the model, the researchers determined how many people would be infected and undiagnosed without age-based screening. They computed how far the disease would have progressed.
Next, they looked at the effect of screening the entire population in that age range. They looked at how screening and detection would affect progression to advanced liver disease, if infected, and to death.
Age-based screening is worth it, they conclude.
''The age-based screening program could prevent more than 100,000 cases of advanced liver disease and save almost 60,000 lives over the course of the lifetime of this group born from 1946 to 1970," McGarry tells WebMD.
It would prevent more than 7,000 liver transplants, McGarry tells WebMD.
The eligible population, she estimates, would be about 101 million.
The test is a blood test and costs about $30, she says. It detects antibodies to the virus. If that test is positive, a second test is done to confirm.
Earlier treatment due to earlier detection would result in a net cost saving to the health care system, the researchers say.
Age-Based Hepatitis C Testing: Other Views
Currently, the U.S. Preventive Services Task Force, which issues recommendations on testing and other health issues, does not recommend routine testing, says Virginia Moyer, MD, chair of the task force.
The recommendation on hepatitis C testing is not technically current, she says, as it was issued in 2004. "Our goal is to update recommendations every five years, sooner if important new evidence becomes available," she tells WebMD.
"I think this one has been of lower priority for updating, perhaps because there has not been a lot of new evidence, nor has there been a widespread call for a change. From the point of view of the task force, this is the kind of evidence that might help us move forward with an update."
The model alone would not be enough to change the recommendation, says Moyer, who is also professor of pediatrics at Baylor College of Medicine, Houston.
"We would not base a recommendation solely on modeling, but we do use modeling to help us understand the trade-offs, which is what these authors are attempting to evaluate," she says.
When the task force does take up the issue of hepatitis C testing, "I think this is a piece of information they need to take a look at," says Aaron Glatt, MD, a spokesman for the Infectious Diseases Society of America and president of St. Joseph Hospital in Bethpage, N.Y.
He reviewed the findings for WebMD but was not involved in the study.
The researchers should refine the model to zero in on those in the age group with the most risk, he says. "There may be ways to knock down that 100 million people to 40 million," he says.
For instance, he says, by asking about risk factors in the past, some people may be declared low risk. The key, he says, is for people to think of risk factors from decades ago, not current ones.