(P08-026-23) Phase Angle as a Marker of Nutritional Status and Strength in Pediatric Intestinal Failure

Objectives: Bioelectrical impedance analysis (BIA) derived phase angle (PhA) has been gaining attention in the clinical evaluation of nutritional status as it is thought to be a valuable tool to assess malnutrition, strength as well as the relative risk of mortality. PhA is an indicator of cellular health, particularly cell structure, function, as well as cell membrane integrity with higher PhA values suggesting a better health quality with respect to these parameters. Lower PhA may indicate altered cell membrane function and breakdown as a consequence of disease and malnutrition. This study in children with intestinal failure aims to determine whether PhA can be used as a marker of nutritional status and strength.

Methods: Cross-sectional study in children 1-18 years with IF on and off parenteral nutrition. BIA measured resistance (R) and reactance (Xc) were used to calculate BIA-derived PhA as follows: [arctangent (Xc/R) x 180°/π]. Anthropometric measurements including weight, height, mid-upper arm circumference (MUAC), and triceps skinfold thickness were measured on the same day as BIA measurement. Mid-upper arm muscle circumference (MAMC) was calculated using MUAC and triceps skinfold. Strength was assessed by handgrip strength (HGS). Data on subject characteristics and feeding method were collected. Regression analysis was used to assess the relationship between PhA and clinical variables.

Results: Sixty-eight children with IF (46 males), mean age 8.9±4.2 years, 25 dependent on parenteral nutrition were studied. Mean (SD) PhA value was 5.0 (1.0). There was no difference in PhA in patients receiving parenteral nutrition compared to those fully enterally fed. PhA scores were found to be significantly positively associated with MUAC (r²= 0.14, p=0.002), HGS (r²= 0.30, p=0.003), and MAMC (r²= 0.22, p< 0.001). Age was found to have a significant positive effect (p < 0.0001) on the relationship between PhA and MUAC (r²= 0.27), PhA and HGS (r²= 0.30), and PhA and MAMC (r²= 0.29). There was no association between PhA and weight- or height-for-age z-scores.

Conclusions: This is the first study to assess the relationship between PhA and markers of nutritional status in pediatric IF. The relationship between PhA and traditional markers of nutritional status suggest a promising application for PhA in pediatric IF.

Funding Sources: Rare Disease Foundation