Cutoff Value of Phase Angle by Bioelectrical Impedance Analysis at Admission as a Prognostic Factor in Patients with...

Acute heart failure is the most common cause of hospital admission in patients aged > 65 years, with congestion being the predominant symptom. It is widely known that congestion is the main cause of readmission and its association with poor outcomes. This study aimed to determine the cutoff value of the phase angle using bioelectrical impedance analysis in the first 24 h after admission for the prediction of in-hospital mortality and all-cause mortality or rehospitalization 90 day post discharge in patients with acute heart failure. The dataset analyzed for this protocol included 219 patients who presented to the emergency department with acute heart failure, of whom 115 died during hospitalization, 90 days post discharge, or were readmitted during the same period. Through univariable analysis using Cox proportional hazards regression analysis, potential predictors were identified, and a multivariable Cox proportional hazard model was used to identify the significant prognostic factors associated with patient survival and to control for confounding variables. Analysis of the phase angle adjusted by different predictors using restricted cubic splines revealed that lower values were directly associated with the risk of 90 day readmission or death post discharge, particularly when the cutoff value of PhA was <4.0°. All developed models showed moderate discriminatory ability (C-statistic < 0.80); however, the in-hospital mortality model demonstrated the highest discrimination ability (C-statistic, 0.75).