Association between pressure ulcers and phase angle in older adults residing in long-term care facilities

Background: In this study, we aimed to investigate the association between the presence of pressure ulcers and body composition parameters in older residents of long-term care facilities and identified the most relevant indicators. Methods: This cross-sectional observational study assessed 156 residents. Body composition was measured, including body mass index (BMI) and phase angle (PhA). Functional assessments included the Barthel index (BI), and Clinical Frailty Scale. The participants were classified into two groups based on the presence or absence of pressure ulcers. Group comparisons and receiver operating characteristic analyses were used to determine the area under the curve (AUC) and cutoff values. The diagnostic performance of the combined cutoff values was also examined. Binary logistic regression was used to evaluate the association between PhA and the presence of pressure ulcers. Results: Twenty (12.8%) participants had pressure ulcers, 90% of which were mild-stage. PhA was lower in the pressure ulcer group (p < 0.001), with an optimal cutoff value of 3.1° (AUC 0.72). Using the cutoff values derived from each assessment, the combination of PhA with BI or BMI improved the AUC to a maximum of 0.78. Logistic regression demonstrated a significant association between PhA and the presence of pressure ulcers (p < 0.05). Conclusion: Phase angle may serve as a complementary biomarker for pressure ulcer risk assessment and may be more useful when combined with functional and nutritional indicators. The use of body composition parameters for noninvasive risk assessment could play an important role in future pressure ulcer prevention strategies.