Bioelectrical impedance analysis is a useful bedside technique to assess malnutrition in cirrhotic patients with and without ascites

Protein-calorie malnutrition is associated with poor prognosis in chronic l iver disease, but reliable assessment is hampered by changes in body water. We prospectively evaluated the effect of fluid retention on bioelectrical impedance analysis (BIA) as a simple method for the estimation of body cell mass (BCMBIA) in 41 patients with cirrhosis (n = 20 with ascites; n = 21 w ithout ascites) using total body potassium counting (BCMTBP) as a reference method. Arm muscle area and creatinine-derived lean body mass were compare d with total body potassium data. In patients total body potassium was 24.4 % lower than in controls and this loss was more severe in patients with asc ites (-34.1%; P <.01). BCMBIA and BCMTBP were closely correlated in control s (r(2) =.87, P <.0001), patients without ascites (r(2) =.94, P <.0001) and patients with ascites (r(2) =,56, P <.0001). Removal of 6.2 +/- 3 L of asc ites had only minor effects on BCMBIA (deviation of -0.18 kg/L ascites). Li mits of agreement between both methods were wider in patients with ascites than in patients without (6.2 vs. 4.2 kg). In patients without ascites arm muscle area (r(2) =.64; P <.001) and lean body mass (r(2) =.55; P <.001) co rrelated significantly with total body potassium, but not in patients with ascites. For assessment of protein malnutrition in patients with cirrhosis, body cell mass determination by use pf BIA offers a considerable advantage over other widely available but less accurate methods like anthropometry o r the creatinine approach. Despite some limitations in patients with ascite s, BIA is a reliable bedside tool for the determination of body cell mass i n cirrhotic patients with and without ascites.