Predictors of protein-energy wasting in haemodialysis patients: a cross-sectional study.

Abstract

Protein-energy wasting (PEW) is a highly prevalent condition in haemodialysis patients (HD). The potential usefulness of nutritional-inflammatory markers in the diagnosis of PEW in chronic kidney disease has not been established completely. We hypothesised that a combination of serum albumin, percentage of mid-arm muscle circumference and standard body weight comprises a better discriminator than either single marker of nutritional status in HD patients. A cross-sectional study was performed in 80 HD patients. Patients were categorised in two groups: well-nourished and PEW. Logistic regression analysis was applied to corroborate the reliability of the three markers of PEW with all the nutritional-inflammatory markers analysed. PEW was identified in 52.5% of HD patients. Compared with the well-nourished patients, PEW patients had lower body mass index, serum pre-albumin and body cell mass (all P<0.001) and higher C-reactive protein (s-CRP) (P<0.01). Logistic regression analyses showed that the combination of the three criteria were significantly related with s-CRP >1mg dL(-1) , phase angle <4°, and serum pre-albumin <30mg dL(-1) (all P<0.05). Other indicators, such as lymphocytes <20% and Charlson comorbidity index, were significantly involved (both P<0.01). A receiver operating characteristic curve (area under the curve) of 0.86 (P<0.001) was found. The combined utilisation of serum albumin, percentage of mid-arm muscle circumference and standard body weight as PEW markers appears to be useful for nutritional-inflammatory status assessment and adds predictive value to the traditional indicators. Larger studies are needed to achieve the reliability of these predictor combinations and their cut-off values in HD patients and other populations.