Clinical states of cirrhosis and competing risks

The clinical course of cirrhosis is mostly determined by the progressive increase of portal hypertension, hyperdynamic circulation, bacterial translocation and activation of systemic inflammation. Different disease states, encompassing compensated and decompensated cirrhosis and a late decompensated state, are related to the progression of these mechanisms and may be recognised by haemodynamic or clinical characteristics. While these disease states do not follow a predictable sequence, they correspond to varying mortality risk. Acute-on-chronic liver failure may occur either in decompensated or in compensated cirrhosis and is always associated with a high short-term mortality. The increasing severity of these disease states prompted the concept of clinical states of cirrhosis. A multistate approach has been considered to describe the clinical course of the disease. Such an approach requires the assessment of the probabilities of different outcomes in each state, which compete with each other to occur first and mark the transition towards a different state. This requires the use of competing risks analysis, since the traditional Kaplan-Meier analysis should only be used in two-state settings. Accounting for competing risks also has implications for prognosis and treatment efficacy research. The aim of this review is to summarise relevant clinical states and to show examples of competing risks analysis in multistate models of cirrhosis.