Should We Be Screening for Hepatitis C?
Abstract & Commentary
By Joseph E. Scherger, MD, MPH
Synopsis: Among veterans with risk factors for hepatitis C, a screening program yields results of limited value. The number needed to screen to yield a treatable case of hepatitis C was 451, but the number needed to screen for a successful outcome was more than 4000.
Source: Mallette C, et al. Outcome of screening for hepatitis C virus infection based on risk factors. Am J Gastroenterol. 2008;103:131-137. Summary review by Essential Evidence Plus:Daily POEM: Screening for hepatitis C has minimal benefit (NNS = 4000). Wiley Subscriptions Services. April 10, 2008.
Hepatitis C is the most common viral hepatitis leading to chronic liver disease. Most patients with antibodies to hepatitis C do not develop liver disease even with positive RNA viral levels. The Centers for Disease Control and Prevention recommends screening high risk patients for hepatitis C (HCV) infection. The U.S. Preventive Services Task Force found insufficient evidence to support this recommendation. The current treatment for HCV is toxic and expensive, and the long term successful outcome as measured by clearing of the viral levels is less than 50%. Given all this, should we be screening high risk patients and who should we be referring for evaluation and treatment?
Two large VA studies have been published this year on outcomes of screening high risk patients (Mallette, et al and Groom, et al).1 In the Mallette study review here, veterans at the Providence, RI Veterans Affairs Medical Center (VA) were given a questionnaire to assess for risk of hepatitis C. High risk factors were: serving in Vietnam, receiving blood products before 1992, intravenous drug or cocaine use, 5 or more alcoholic drinks per day for 10 or more years, 10 or more lifetime sexual partners, any male homosexual experience, blood exposure, hemodialysis, tattoo, current HIV or hepatitis B, or history of unexplained liver disease. Between October 1998 and May 2004, 25,701 patients were assessed and 8,471 had at least one risk factor. Of them, 5646 agreed to be tested, and 412 patients had a positive HCV test (7.3%). Of these, 260 were new diagnoses, and the authors used this number to support the screening program.
What happened to these 260 patients? One hundred forty-eight could not be reached for further evaluation reflecting the nature of this population with high levels of drug use and alcoholism. Among the 112 that did undergo a complete evaluation, about half (57) were treatment candidates. Only 18 underwent a full course of treatment and 6 had a sustained virologic response (less than 1 in 4000 screened). While the authors support the use of the screening program, the reviewers for Daily POEM (Wiley Subscription Services) consider screening for hepatitis C of minimal benefit. The results from a similar study at the Minneapolis VA by Groom, et al, yielded similar results.1
Screening, evaluation and treatment of hepatitis C is highly controversial. Given the high prevalence of this condition in the population, whether to screen or not and whom to evaluate and treat are vitally important questions. Enormous amounts of money are being spent on hepatitis C in a health care system strapped for funds.
I am the medical director of the indigent care program for San Diego County and am responsible for the medical policies, including screening and referral for evaluation and treatment of hepatitis C patients. We support hepatitis C screening of at risk patients, mainly because we think that this knowledge is important to reduce risk of spread through sexual relations and the use of blood products. Our local liver clinics are willing to treat any patients with a positive viral load, which is about 50% of antibody positive patients. However, based on the toxicity, expense and limited success of treatment, we only support referral of patients with a positive ALT level (at least 50% above normal). This is because 85% of HCV patients will not develop hepatitis and waiting for early evidence of disease does not significantly change the outcome. Similar policies are used by other public health agencies in an effort to be cost effective.
Specialty physicians want to treat and stamp out disease in their organ system, and gastroenterologists/hepatologists are no exception. Much has been learned about the treatment of chronic HCV, and the treatment regimens will improve with time and experience. However, mass evaluation and treatment of HCV today is not the best use of limited health care resources. We need to be selective in our use of screening and treatment. Many of the veterans in these studies voted with their feet and did not pursue evaluation and treatment. I think we need to stay very selective in our screening, evaluation and treatment of HCV. If I were HCV positive and had a normal ALT, I would sit tight and not undergo a liver biopsy or treatment at this time.
1. Groom H, et al. J Clin Gastroenterol. 2008;42:97-106.