Phase angle and urea-to-creatinine ratio in hospitalized cancer patients.

e24056 Background: Malnutrition, impaired cellular integrity, and hypercatabolic states are common in hospitalized cancer patients and are associated with adverse clinical outcomes. Phase angle (PhA), derived from bioelectrical impedance analysis, reflects cellular membrane integrity and physiological resilience, while the urea-to-creatinine ratio (UCR) serves as a surrogate marker of protein catabolism. This study evaluated the association of PhA and UCR measured at hospital admission with length of stay (LOS) and in-hospital mortality in oncology patients. Methods: This prospective observational study included 104 adult oncology inpatients. PhA and body composition parameters were assessed at admission using bioelectrical impedance analysis. Laboratory data were used to calculate UCR. Patients were stratified by median PhA (4.5°) and by elevated UCR. LOS was analyzed as a continuous variable and dichotomized at the 75th percentile. Associations were evaluated using nonparametric tests, correlation analyses, and multivariable logistic regression. Results: Median LOS was 3 days (interquartile range [IQR], 2–7). UCR showed a moderate positive correlation with LOS (r = 0.449; p < 0.001), whereas PhA was not linearly correlated with LOS (r = −0.124; p = 0.226). Patients with lower PhA had reduced muscle mass, lower appendicular muscle index, and higher UCR, indicating poorer nutritional and functional status, although LOS did not differ significantly between PhA strata (p = 0.336). Elevated UCR was associated with prolonged LOS (44.8% vs 15.4%; p = 0.002) and remained the only independent predictor in multivariable analysis (odds ratio [OR], 1.057 per unit increase; p = 0.015). In mortality analyses (8 deaths; 7.8%), PhA as a continuous variable was associated with in-hospital mortality in the initial multivariable model (OR, 0.20 per degree increase; p = 0.031). This association was attenuated after stepwise adjustment, likely due to the limited number of events. Conclusions: UCR measured at hospital admission is independently associated with prolonged hospitalization, reflecting an underlying hypercatabolic phenotype. PhA demonstrates a clinically relevant association with in-hospital mortality, capturing loss of cellular integrity and physiological resilience. The combined assessment of PhA and UCR may provide complementary prognostic information and support early risk stratification in hospitalized cancer patients.