Frequency and Characteristics of Overestimated Renal Function in Japanese Patients with Chronic Liver Disease and Its Relation to Sarcopenia

Renal dysfunction and sarcopenia are important prognostic factors in patients with chronic liver disease (CLD). Muscle atrophy can cause the overestimation of renal function based on serum creatinine. However, the frequency of overestimated renal function in Japanese patients with CLD and its relationship with sarcopenia are unclear. In present study, we evaluated the frequency of overestimated renal function, defined as a >20% higher eGFR using creatinine than using cystatin C, in 307 patients with CLD as well as its relationship with indicators of sarcopenia. In total, 24.8% of patients had overestimated renal function. In a multivariate regression analysis, liver cirrhosis (p = 0.004) and psoas muscle mass index (p = 0.049) were significantly associated with overestimated renal function. Loss of skeletal muscle mass was significantly more frequent in both male and female patients with overestimated renal function than without. In males, the loss of muscle strength and rate of sarcopenia, defined as loss of muscle mass and strength, were significantly higher in patients with than without overestimated renal function. The high frequency of overestimated renal function in Japanese patients suggests that indicators of renal function should be carefully considered; furthermore, monitoring and interventions for both renal function and sarcopenia are needed in patients with CLD.