Salivary caffeine clearance predicts survival in patients with liver cirrhosis

Quantification of liver function in patients with cirrhosis is difficult. Caffeine clearance (CCI) has been suggested as a more exact method than those commonly used. The aim of this work was to assess the usefulness of CCl in survival prediction for these patients.

Thirty-four patients with cirrhosis of the liver of various causes were included; 19 were class A or B in Child-Pugh's classification and 15 were class C. CCl was determined from saliva samples. The mean length of follow-up was 33.8 months. A bivariant survival analysis was carried out following the Kaplan-Meier method, together with a multivariant analysis using the Cox proportional hazards model.

Twelve patients died during the follow-up period. CCl values < 0.24 ml/kg/min, age > 60 yr, and nonalcoholic cause of cirrhosis were factors predicting lower survival. CCl was the only independent predictive factor in the multivariant analysis.

CCl enables us to predict survival in cirrhotic patients and, considering its harmlessness, simplicity, and cost, can be used as a routine procedure in the assessment of these patients.