THE EFFECT OF INTERFERON ON THE LIVER IN CHRONIC HEPATITIS-C - A QUANTITATIVE-EVALUATION OF HISTOLOGY BY METAANALYSIS

Background/Aims: Several randomized clinical trials of interferon in c hronic hepatitis C have examined the histological changes in paired bi opsy specimens. We have attempted a quantitative evaluation by metaana lysis. Methods: Randomized Clinical Trials found by MEDLINE search wer e included if: a) they compared different IFN regimens with non-active treatment or with each other, b) they obtained biopsies before starti ng and at the time of stopping IFN in a sizable proportion of the trea ted and control patients, and c) they assessed the biopsy-specimens se mi-quantitatively according to Scheuer's numerical scoring system or K nodell's Histological Activity Index, with quantitation of fibrosis an d of lobular, portal and periportal necroinflammation. Results: Sevent een trials mere identified, in which 1223 adult patients had been stud ied. AU trials homogeneously pointed towards a favorable interferon ef fect. The pooled data show a statistically significant histological im provement in treated patients as compared with controls for each of th e four Histological Activity Index components and for the total Histol ogical Activity Index score (overall improvement was -0.82 in favor of interferon, p < 0.0001, 95% Confidence Interval -1.25 to -0.40). In t he ten trials reporting histological changes separately in biochemical responders (primary and sustained responders) and non-responders, his tological improvement was confined to the subset of biochemical respon ders. No change or very little change occurred in non-responders.Concl usions: Interferon treatment in chronic hepatitis C significantly impr oves liver histology. The effect of interferon is closely related to b iochemical response. Studies assessing histological outcome 1 year or more after interferon treatment in long-term responders and comparativ ely in non-responders or relapsers mould be important to confirm the r egression of the necroinflammatory process in the former, as suggested by the normal serum alanine aminotransferase levels.