Serum albumin and nutritional status.

Serum albumin concentration is frequently used to define nutritional status. To validate this relationship, 161 body composition studies were performed on 102 patients simultaneously with protein electrophoresis. The body cell mass represented by the exchangeable potassium to total body water ratio correlated significantly (p < 0.001) with the serum albumin concentration (r = 0.59) and significantly (p < 0.001) to total protein (r = 0.59). However, in both cases the 95% confidence limits about the regression were wide. In 24 of 54 patients (44%) with a normal nutritional state, as defined by body composition, the serum albumin was abnormal. In 12 of 107 (11.2%) patients with malnutrition, the serum albumin was normal. Patients with more than one study were divided into 3 groups depending on the changes in their nutritional state as defined by their body composition. Serum albumin did not consistently reflect the significant body compositional changes observed. The data indicate that serum albumin is a valid measure of nutritional state for epidemiological surveys. However, due to the low sensitivity and specificity it is a poor parameter for evaluating the individual patient's nutritional state.