Prevalence of hepatitis A virus and hepatitis B virus immunity in patientswith polymerase chain reaction-confirmed hepatitis C: Implications for vaccination strategy

OBJECTIVES: Administration of vaccine for hepatitis A virus (HAV) and hepat itis B virus (HBV) is recommended for patients with chronic hepatitis C (CH C) because of the potential for increased severity of acute hepatitis super imposed on existing liver disease. The aim of this study is to determine th e prevalence of antibodies directed against HAV and HBV in patients with CH C, analyze demographic and risk factors associated with this prevalence, an d develop a cost-effective vaccination strategy. METHODS: We reviewed records from 1092 CHC patients. Demographics and infor mation regarding risk factors were obtained by history and questionnaire ad ministered to all patients. The costs of vaccination and antibody testing w ere determined, based on standard laboratory and clinic charges at our inst itution. HAV and HBV markers were correlated to race, age, and risk factors . RESULTS: Of the total population studied (n = 1092), 72% were African-Ameri cans, 27% white, and 1% others. Of 671 CHC patients tested for anti-HAV IgG , 252 (38%) were positive. Of 743 CHC patients tested for HBV antibodies (a nti-hepatitis B core IgG or anti-hepatitis B surface), 494 (67%) were posit ive. African-Americans are more likely to have antibodies to HAV and HBV (6 7% and 75%, respectively) compared to whites (27% and 20%). The prevalence of anti-HAV was 76% in patients >60 yr, 34% in the 40- to 60-yr-old age gro up, and 21% in patients <40 yr. The highest prevalence of HBV antibodies wa s found in patients between the ages of 40-60 yr. No HCV risk factors were associated with increased HAV risk. In CHC patients with HBV antibodies, ho wever, illicit injection drug use was the predominant risk factor. CONCLUSIONS: The prevalence of anti-HAV in patients with CHC was found to b e similar to that of the general population in the United States (33% accor ding to recent Centers for Disease Control data), consistent with the hypot hesis that the two infections do not share risk factors. Because the preval ence of HAV immunity is low in CHC patients <40 yr, empiric HAV vaccination is cost effective. If two doses of vaccine are to be given, however, antib ody testings of all HCV patients is indicated. In the subset of patients >6 0 yr of age or who are African-American, where the prevalence of HAV exposu re is considerably higher, it would be cost effective to check the antibody ($36.00), before vaccination ($97.00). The prevalence of HBV antibodies, h owever, is significantly increased in patients with CHC compared with the g eneral population (5.3% per the Centers for Disease Control), likely as a r esult of exposure to similar parenteral risk factors. I-IBV antibody testin g ($26.00 per test) should, therefore, be undertaken in all CHC patients wh o are hepatitis B surface antigen negative, as this approach is cost-effect ive compared to empiric HBV vaccination ($438.00 for a three injection cour se). (C) 2001 by Am. Cell. of Gastroenterology.