Universal Index for Cirrhosis (UIC index): The development and validation of a novel index to predict advanced liver disease

Aim: The purpose of this study was to create and validate a novel serological diagnostic index to predict cirrhosis of all etiologies. Methods: This was a retrospective observational study of 771 patients, age >18 years, who underwent a liver biopsy. The stage of fibrosis and routine laboratory values were recorded. The data were randomly separated into 2 datasets (training 50% and testing 50%). A stepwise logistic regression model was used to develop the novel index. The area under the curve of receiver operating characteristic (AUROC) was applied to compare the new index to existing ones (Fibro-Q, FIB4, APRI, AAR), which was also validated in the testing dataset. Results: Variables associated with the presence of cirrhosis were first assessed by univariate analysis then by multivariable analysis, which indicated serum glutamic-oxaloacetic acid transaminase, serum glutamic-pyruvic transaminase, international normalized ratio, albumin, blood urea nitrogen, glucose, platelet count, total protein, age, and race were the independent predictors of cirrhosis (P<0.05). Regression formula for prediction of cirrhosis was generated and a novel index was subsequently created. The diagnostic performance of the novel index for predicting cirrhosis was assessed using the receiver operating characteristic curve. The new index had significantly higher AUROC (0.83, 95% CI: 0.79-0.87) than Fibro-Q (0.80, 95% CI: 0.76-0.85), FIB4 (0.79, 95% CI: 0.74-0.83), APRI (0.74, 95% CI: 0.69-0.78), and AAR (0.72, 95% CI: 0.67-0.78). Conclusion: The novel index had the highest AUROC curve when compared with current indices and can be applied to all etiologies of chronic liver disease.