Discriminant function for prognostic indexes and probability of death in chronic severe hepatitis B

Background We aimed to determine a discriminant function for prognosis in chronic severe hepatitis B (CSHB) by discriminant analysis of prognostic indexes and probability of death. Methods. In 205 patients with chronic severe hepatitis B (101 patients in the survival group and 104 patients in the death group), we carried out discriminant analysis of serum total bilirubin, prothrombin activity, white blood cells, creatinine, maximum depth of ascites, hepatic encephalopathy, singultus, and digestive tract hemorrhage. Results. The discriminant function was V = 0.00043 x total bilirubin (muM) - 0.025 x prothrombin activity (%) + 0.056 x white blood cells (10(9)/l) + 0.00284 x creatinine (muM) + 0.0014 x maximum depth of ascites (mm) + 0.724 x hepatic encephalopathy score + 0.078 x singultus score + 0.457 x digestive tract hemorrhage score -2.488. The correctness of the function for predicting death in the death group was 92.3%, and that for predicting survival in the survival group was 96.0%. When the V values were -infinity, -4.595, -2.197, -1.386, -0.405, 0.405, 1.386, 2.197, 2,944, 4.595, and infinity, a posterior probabilities of death were 0%, 5%, 10%, 20%, 40%, 60%, 80%, 90%, 95%, 99%, and 100%, respectively. Conclusions. The discriminant function is an objective, convenient, and practical method to assess the prognosis of chronic severe hepatitis B.