Incremental value of body composition indices in discriminating poorly controlled asthma in children: a cross-sectional study

Asthma is the most common chronic respiratory disease in children, yet a considerable proportion of children have poorly controlled asthma despite advances in treatment. Traditional assessment models based on clinical indicators and lung function parameters show limited discriminatory ability. This study evaluated whether bioelectrical impedance analysis (BIA)-derived body composition indices—extracellular water-to-total body water ratio (ECW/TBW), phase angle (PhA), and visceral fat area (VFA)—improve the discrimination of poorly controlled asthma in children beyond traditional clinical assessments.