A case-control study of the factors associated with spontaneous resolutionof hepatitis C viremia

OBJECTIVE: Infection with the hepatitis C virus (HCV) becomes chronic in 85 % of the infected individuals. We studied risk factors that may predict cle arance of HCV. METHODS: A case-control study compared the association between risk factors and viral clearance. Viral clearance was defined as presence of a positive HCV antibody test plus negative HCV test by polymerase chain reaction (PCR ). Forty-four cases and 214 controls with persistent viremia were identifie d in a database of patients evaluated at the Gastroenterology Clinic of the University of New Mexico. RESULTS: Of all 258 HCV-antibody-positive patients,17% had a negative test by PCR. The multivariate logistic regression revealed that a history of par enteral exposure and a long time interval since the most recent exposure we re both associated with an increased likelihood of persistent viremia, wher eas subjects who had been monogamous for longer time periods were more like ly to have cleared HCV from their serum. A low serum level of ferritin also conferred protection against persistent viremia. Case and control subjects did not differ with respect to their demographic characteristics, occurren ce of comorbid disease, previous medical history, occurrence of sexually tr ansmitted diseases, blood group, and risky health or sexual practices. CONCLUSIONS: These data suggest that route of exposure and time when exposu re occurred an important in the development of persistent HCV infection. (A m J Gastroenterol 1999;94:668-673. (C) 1999 by Am. Cell. of Gastroenterolog y).