The U.S. Preventive Services Task Force now recommends routine hepatitis C virus screening for individuals at high risk, and one-time screening for adults born between 1945 and 1965.
The recommendation marks a change from 2004 when the U.S. Preventive Services Task Force (USPSTF) recommended against screening in adults not at increased risk, and found insufficient evidence for screening those at high risk. The update, published online June 25 in Annals of Internal Medicine, comes on the heels of a similar recommendation May 10 from the Centers for Disease Control and Prevention (MMWR 2013;62[18]:357-61).
Both the USPSTF and the CDC cite recent evidence that indicates increased HCV risk among baby boomers, as well as substantial evidence of improved outcomes with treatment, and both note that screening could have important public health implications (Ann. Intern. Med. 2013 June 25 [doi:10.7326/0003-4819-159-5-201309030-00672]).
Courtesy US. Dept of Veterans Affairs
According to Dr. Albert Siu of the U.S. Preventive Services Task Force, three out of four patients with Hepatitis C are baby boomers.
"Baby boomers account for three out of four people with hepatitis C," according to Dr. Albert Siu of the USPSTF and the Mount Sinai School of Medicine, New York. "Many people in this age group contracted hepatitis C from a blood transfusion or unknown or unreported high-risk behaviors."
Although many of these adults may be asymptomatic, the evidence is convincing that one-time screening could identify millions who are infected before they develop serious liver disease, Dr. Siu noted in a statement.
The prevalence of HCV infection peaked in 2001 at 3.6 million persons, and the yearly incidence has declined from more than 200,000 cases in the 1980s to 16,000 in 2009.
However, the overrepresentation of those born between 1945 and 1965 among the infected population is concerning, and it may be associated with blood transfusions received before the introduction of screening in 1992. A history of other risk factors for exposure decades earlier could also account for the disease burden in this population, according to the USPSTF report.
Of note, many adults in this age group are unaware of their infection.
"A risk-based approach may miss detection of a substantial proportion of the HCV-infected persons in the birth cohort because of a lack of patient disclosure or knowledge about prior risk status," according to the USPSTF report. "As a result, one-time screening for HCV infection in the birth cohort may identify infected patients at earlier stages of disease who could benefit from treatment before developing complications from liver damage."
HCV infection is the leading cause of complications from chronic liver disease. In fact, HCV-related end-stage liver disease is the most common indication for liver transplants among U.S. adults, accounting for more than 30% of cases.
"Studies suggest that about one-half of the recently observed threefold increase in incidence of hepatocellular carcinoma is related to acquisition of HCV infection 2-4 decades earlier," according to the task force report.
The USPSTF concluded that the benefit of screening baby boomers is likely similar to the benefit of screening those at high risk and outweighs any risks of harm, such as the possibility of overtreatment.
The task force also concluded that although birth cohort screening is likely less efficient than risk-based screening, birth cohort screening will likely benefit a greater number of individuals overall. In fact, birth cohort screening provides nearly twice the benefit of risk-based screening, according to a modeling study reviewed by the USPSTF.
The task force concluded with moderate certainty that screening in both the high-risk and baby boomer populations is of moderate net benefit.
Baby boomers not at otherwise increased risk need to be screened only once. Adults at any age who are at increased risk of HCV because of injection drug use should be screened periodically. The USPSTF found no evidence for a specific recommendation regarding screening frequency.
The task force’s recommendations, as well as a fact sheet explaining the recommendation statement, can be viewed here.