New concepts on the clinical course and stratification of compensated and decompensated cirrhosis

The clinical course of cirrhosis has been typically described by a compensated and a decompensated state based on the absence or, respectively, the presence of any of bleeding, ascites, encephalopathy or jaundice. More recently, it has been recognized that increasing portal hypertension and several major clinical events are followed by a marked worsening in prognosis, and disease states have been proposed accordingly in a multistate model. The development of multistate models implies the assessment of the probabilities of more than one possible outcome from each disease state. This requires the use of competing risks analysis which investigates the risk of several competing outcomes. In such a situation, the Kaplan-Meier risk estimates and the Cox regression may be not appropriate. Clinical states of cirrhosis presently considered as suitable for a comprehensive multistate model include: in compensated cirrhosis, early (mild) portal hypertension with hepatic venous pressure gradient (HVPG) > 5 and < 10 mmHg, clinically significant portal hypertension (HVPG >= 10 mmHg) without gastro-esophageal varices (GEV), and GEV; in decompensated cirrhosis, a first variceal bleeding without other decompensating events, any first non-bleeding decompensation and any second decompensating event; and in a late decompensation state, refractory ascites, sepsis, renal failure, recurrent encephalopathy, profound jaundice, acute on chronic liver failure, all predicting a very short survival. In this review, we illustrate how competing risks analysis and multistate models may be applied to cirrhosis.