Relationships between Indices of Arm Anthropometry,  Bioimpedance, and Laboratory in Maintenance Hemodialysis  Patients

Abstract Background: Maintenance hemodialysis patients often experience protein- calorie malnutrition. Our aim is to evaluate the independent prediction accuracy of bioelectrical impedance analysis derived variables by the measurements of upper arm anthropometry and clinical laboratory indexes for evaluation of nutritional status of hemodialysis patients. Furthermore, the relationship between measurements of upper arm anthropometry and clinical laboratory indexes and cross –sectional evaluation of the prevalence of malnutrition with the use of the norms and thresholds were done. Methods: In a retrospectively cross- sectional survey of 32 stable hemodialysis patients (aged 28 to 82 years) in hemodialysis unit of Taipei Municipal Zhongxiao Hospital, we evaluated measurements of upper arm anthropometry with measurements of single frequency bioelectrical impedance analysis and clinical laboratory indexes. Results: The comparisons between measurements of upper arm anthropometry with measurements of single frequency bioelectrical impedance analysis and some of clinical laboratory indexes were statistically significant. This study further found that both mid-arm fat area and triceps skin-fold thickness were independent contributors to percent fat mass after adjustment for body mass index and gender in the hierarchical multiple regression models. This study also demonstrated that mid-arm muscle circumference, or mid-arm muscle area, or corrected mid-arm muscle area independently predicted height normalized indices of fat-free mass, respectively, after adjustment for body mass index and gender in the hierarchical multiple regression models. Prediction equations for height normalized indices of lean body mass and percent fat mass were showed. The prevalence of protein wasting measured by mid-arm muscle circumference (50%) appears to be equivalent to that measured by serum albumin concentration (50%). Conclusions: Mid-arm muscle and fat variables by upper arm anthropometry correlated with nutritional variables of single frequency bioelectrical impedance analysis and clinical laboratory indexes. Mid-arm muscle and fat variables by upper arm anthropometry were independent predictors of body composition regarding height-normalized indices of fat-free mass and percent fat mass of hemodialysis patients even after adjustment of gender and body mass index.