Hand-grip muscle strength, lean body mass, and plasma proteins as markers of nutritional status in patients with chronic renal failure close to start of dialysis therapy

Abstract

We studied 115 patients (69 men, 46 women) with chronic renal failure (CRF) aged younger than 70 years close to the start of dialysis therapy to assess the prevalence of malnutrition and study the relationship between various nutritional parameters in these patients. Nutritional status was classified by means of subjective global assessment. Anthropometric measurements (AMs) were performed, and hand-grip strength (HGS) was measured using the Harpenden dynamometer. Body composition, including lean body mass (LBM), was evaluated by dual-energy x-ray absorptiometry (DXA), and LBM was also estimated by means of AMs and creatinine kinetics (CK). The mean age of the patients was 52 +/- 12 years, and creatinine clearance was 9 +/- 3 mL/min. Malnutrition was seen in 53 patients (48%). As expected, malnourished patients differed in several aspects from well-nourished patients. LBM (estimated by all methods), fat mass (FM), HGS, creatinine clearance, and transthyretin and vitamin A levels were less in malnourished patients, whereas serum albumin levels did not differ. Estimates of LBM by means of DXA, AMs, and CK correlated well with each other. Although DXA and AMs gave similar mean values, LBM was an average of 8 kg less estimated by means of CK, and Bland-Altman plots showed the best agreement between AMs and DXA. HGS showed a strong correlation to LBM (regardless of method) in both men and women. Serum albumin level was not related to HGS or LBM, whereas significant correlations were found between serum albumin level and albumin losses in urine, C-reactive protein (CRP) level, and creatinine clearance. Multiple logistic regression showed that low HGS, low percentage of FM, female sex, and high serum CRP levels were independent factors associated with malnutrition, whereas serum albumin level and percentage of LBM did not reach statistical significance. In conclusion, the present study shows a high prevalence of malnutrition in predialysis patients with CRF and suggests that HGS is a reliable, inexpensive, and easy-to-perform nutritional parameter in patients with CRF. Conversely, serum albumin level seems to be a poor nutritional marker in patients with advanced CRF.