Hepatitis C, cryoglobulinemia, and cirrhosis: A meta-analysis

Abstract

Approximately 40% of patients with chronic hepatitis C virus (HCV) infection develop detectable serum cryoglobulins or cryoprecipitates (CP), although most do not show clinical or physical signs of syndromic cryoglobulinemia. Although association of HCV with the extrahepatic complications of cryoglobulinemia is widely recognized, the relationship of cryoglobulinemia with liver disease is unclear. We wished to study the relationship between CP and cirrhosis and to determine whether the development of CP is a true covariate for progressive liver disease or a confounding variable that impacts cirrhosis because of patient age, duration of disease, or differences in gender. We undertook a meta-analysis of 19 studies published between 1994 and 2001. The incidence of cirrhosis was compared in patients with and without CP after logistic regression adjustments for accepted risk factors for progressive liver disease, including age, gender, and estimated duration of disease (EDD). A total of 2,323 patients with chronic hepatitis C were identified, with 1,022 (44%) having detectable CP. Cirrhosis was present in 40% of patients with CP but only 17% of patients without CP (total χ² = 141.69, P < .001). After adjusting for age, gender, and estimated duration of disease by logistic regression, the combined odds ratio for incidence of cirrhosis in patients CP positive versus CP negative was 4.87, (95% CI: 3.32, 7.15), indicating a highly significant association between cirrhosis and cryoglobulinemia. In conclusion, cryoglobulins may be a useful prognostic indicator for increased risk of cirrhosis with chronic hepatitis C.