Bioelectrical impedance-derived phase angle as a contextual indicator for steatotic liver disease and hepatic fat...

Steatotic liver disease (SLD) is highly prevalent among individuals with metabolic risk factors, highlighting the need for accessible, non-invasive tools that can support nutritional and clinical risk contextualization. Phase angle, derived from bioelectrical impedance analysis, reflects cellular integrity and body composition and is widely used in nutritional assessment. In this cross-sectional study, 495 adults underwent multi-frequency bioelectrical impedance analysis and hepatic fat evaluation using the controlled attenuation parameter obtained by FibroScan®. Participants were classified as having SLD based on a controlled attenuation parameter threshold of ≥275 dB/m. Individuals with SLD exhibited significantly higher whole-body and segmental phase angle values compared with those without SLD, and these differences were consistent across age and obesity subgroups (p < 0.05). Whole-body phase angle demonstrated moderate discriminative ability for SLD status (area under the curve = 0.646), supporting its role as a contextual indicator rather than a diagnostic measure. In multivariable logistic regression analyses, phase angle remained independently associated with SLD alongside waist circumference and age, whereas body mass index and body fat percentage were not statistically significant. Additionally, a regression-based model incorporating phase angle and simple anthropometric variables showed good performance in estimating hepatic fat content (area under the curve = 0.807). Overall, these findings indicate that phase angle reflects bioelectrical properties influenced by body composition associated with clinically relevant hepatic steatosis.