['C-type natriuretic peptide (CNP) might be an important regulator of vasodilatation, fluid and sodium balance in liver cirrhosis. We aimed at assessing its regulation and prognostic relevance in liver disease patients.', 'We analyzed NT-proCNP serum levels in 193 patients with chronic liver diseases and 43 healthy controls.', 'Serum NT-proCNP concentrations were significantly elevated in liver disease patients compared to healthy controls, with highest levels in established hepatic cirrhosis, independent of disease etiology. NT-proCNP was associated with complications of liver diseases and portal hypertension, namely ascites, esophageal varices and hepatic encephalopathy. Circulating NT-proCNP correlated inversely with renal function. Importantly, elevated NT-proCNP levels were identified as a predictor of mortality or necessity for transplantation. NT-proCNP levels >2 pmol/L indicated adverse prognosis (sensitivity 66.7%, specificity 72.8%, RR 5.4 [95%-CI 2.6-11.2]).'] Are serum NT-proCNP concentrations elevated in patients with chronic liver diseases and associated with complications and unfavorable prognosis of cirrhosis?