Impact of CDC Recommendations on Age Cohort-Based Screening for HCV in Primary Care
Hugo E. Vargas, MD
Chair, Division of Hepatology, Mayo Clinic
The field of hepatology finds itself at a pivotal moment in its history. We have long recognized hepatitis C virus (HCV) as a masterful foe that evaded many efforts to stop the slow devastation that it yields without successful treatment. Because most hepatologists today rely on the miracle of liver transplantation to rescue our patients from cirrhosis and its complications, we are uniquely positioned to encounter the common and frustrating clinical scenario of the patient who arrives at the diagnosis of HCV the same day it is revealed that cirrhosis is already well established. Since the onset of my clinical efforts more than 20 years ago, I have toiled with a long, challenging therapy anchored on the use of interferon which, pegylated or not, limited my ability to incite enthusiasm even in the most motivated of patients. We are now entering a hopeful era when we will eliminate interferons as a base for our treatment approach and broaden the spectrum of patients we can treat safely. With this promise in front, the question can be fairly asked: how will we define our success?
We have long known that a vast majority of our potential patients have no idea that they can be at risk for a viral infection that is insidious and costly to manage once it has played out its course. The valuable data gleaned from the National Health and Nutrition Examination Survey (NHANES) places the national (excluding homeless and institutionalized people) prevalence of HCV infection at 1.5 percent. Adjusting for those not accounted for in the surveys, we estimate that 4.5 to 5 million Americans may be infected with the virus. One may ask, if these numbers are known, why is there a problem? The sad truth is among those infected, 45 to 85 percent are not even aware of their “at-risk” status and thus lack the motivation to seek screening. Strategies to test those who were covered by the risk-based approach of the 1998 CDC recommendations have, not surprisingly, been less than effective. Some reports place the prevalence of HCV testing in these groups as low as 17 percent. This is why the current CDC recommendation to include non-risk-based, one-time testing of adults born between 1945 and 1965 is an important step to address this deficiency at a timely point in history.1
Using NHANES results and CDC surveillance data, recommendations have been issued to test the baby-boomer generation. CDC noted increases in non-A, non-B hepatitis (read HCV before we had identified it) that steadily increased from 1965 to the late 1980s when HCV was identified. Analysis of birth cohort sets that revealed the disproportionate distribution of HCV infections among surveyed individuals led to the selection of the currently recommended birth cohort. We need to know that the incidence of HCV in this baby-boomer cohort is 3.25 percent, and that 76.5 percent of all HCV-infected Americans are found in this birth cohort of the American population.
We have long known that a vast majority of our potential patients have no idea they can be at risk for a viral infection that is insidious and costly to manage once it has played out its course.
The CDC recommendation arrived at the same time as the impressive headlines of new, potentially all-oral direct antiviral regimens claiming fantastic viral responses in the range of 85 to 95 percent in phase II and early phase III data. It is difficult to contain the excitement of seeing interferon-free options for even my sickest patients come to light, coupled with a recommendation to bring the largest group in society to benefit from treatment to recognition and education about the effective treatments available to them. The U.S. Preventive Services Task Force was convinced, after initial misgivings, to give birth cohort screening an important “B” grade ranking, communicated by the publication of several papers confirming that sustained viral response to HCV treatment leads to less cirrhosis, less hepatocellular carcinoma and decreased demand for expensive care such as liver transplantation.2 Ultimately, this means a decrease in deaths due to HCV.
Does this mean that the work of hepatology is done? My answer is a resounding NO! We have to recognize that however effective, treatment of 5 million Americans will not be easy. Many do not have access to care. Importantly, those incarcerated may return to society with unrecognized disease, unrealized medical coverage, and they will remain a seedbed for future infection. Recent reports from CDC reveal both that injection drug use may be leading to a new wave of infections in younger populations and increased incidence of HCV in men who have sex with men who are infected with HIV. For those patients who are willing to be treated presently, the cost of therapy may exceed $100,000. Success will be defined by how we overcome all those challenges and advocate for our patients, support our primary care colleagues, and expand the pool of HCV treating clinicians to fully help the enormous need.
Dr. Vargas serves as the chair of the AASLD Ethics Committee.
1. Smith, B.D., et al., Recommendations for the identification of chronic hepatitis C virus infection among persons born during 1945-1965. MMWR. Recommendations and reports: Morbidity and mortality weekly report. Recommendations and reports/Centers for Disease Control, 2012. 61(RR-4): p. 1-32.
2. Moyer, V.A., Screening for hepatitis C virus infection in adults: U.S. Preventive Services Task Force recommendation statement. Annals of internal medicine, 2013. 159(5): p. 349-57.