Peripheral platelet count correlates with liver atrophy and predicts long-term mortality on the liver transplant waiting list

Abstract

Several studies have shown a direct role of liver atrophy in the pathogenesis of thrombocytopenia of cirrhosis via reduced production of thrombopoeitin. About 181 patients listed for liver transplantation at a single transplant center were evaluated at the time of listing with laboratory tests and volumetric liver measurements using computed tomography. Expected normal liver volume was calculated using the Heinemann formula. Liver volume ratio (LVR) was calculated as actual liver volume over expected liver volume. Patients were predominantly male (70.7%), with viral hepatitis (60.2%), had a mean age of 51.8 years (SD 8.7), model for end stage liver disease (MELD) of 14 (SD 6.4), LVR of 0.95 (SD 0.3), and platelet count of 105,000/mcL (SD 66,000). Platelet count (P < 0.0001) correlated more strongly with LVR than MELD, MELD components (P = 0.27) or serum albumin (P = 0.003). Platelet count (HR 0.987, 95% CI 0.979-0.994, P = 0.001) was a strong independent predictor of mortality. Patients with platelet count < 100,000/mcL had a shorter survival (935 vs. 1396 days, P = 0.002) and higher death rate (42.2% vs. 23.6%, P = 0.01), but no different transplantation rate (36.7% vs. 33.3%, P = 0.64) compared to those with platelet count ≥ 100,000/mcL. Low platelet count corresponds to higher waiting list mortality and is a sign of advanced liver atrophy.