ASSESSMENT OF NUTRITIONAL-STATUS IN CAPD PATIENTS - SERUM-ALBUMIN IS NOT A USEFUL MEASURE

Introduction. In CAPD patients serum albumin is frequently used as an index of nutritional status, although it is recognized that hypoalbumi naemia may be caused by many factors. We have further examined the rel ationship between serum albumin and nutrition. Methods. Nutritional st atus was assessed by biochemistry, anthropometry, mid-arm muscle circu mference, muscle strength (hand grip and back), and lean body mass (fr om anthropometry, creatinine kinetics and bioimpedance) in a group of 76 stable CAPD patients. Correlations between biochemical and nutritio nal parameters were sought and data were compared between patient grou ps defined by serum albumin (greater than or equal to 37 vs <37 g/l on two occasions 2 months apart) and separately according to subjective global assessment score (normal nutrition, A vs mild to moderate, B, a nd severe, C, malnutrition). Results. In patients with a low SGA score , actual body weight, body mass index, mid-arm muscle circumference, l ean body mass, subscapular skinfold thickness, hand grip strength (mal es and females) and iliac and triceps skinfold thicknesses and back st rength (females only) were all significantly less than in patients wit h a normal SGA score. In contrast, none of these variables differed in either gender when patients were compared according to serum albumin. Serum albumin was correlated with serum creatinine (r = 0.45, P = 0.0 1), daily urine protein excretion (r = -0.42, P = 0.02) and uncorrecte d weekly creatinine clearance (r = -0.39) in females, but not with any index of body composition in either gender. Conclusion. Whilst SGA id entified a patient group with significantly abnormal body mass, muscle mass and muscle strength, serum albumin did not. Serum albumin is not a useful marker of malnutrition in stable patients on CAPD.