The invention provides a system for characterizing a patient undergoing hemodialysis, featuring: 1) a body-worn biometric sensor, worn on a single location of the patient, and featuring: i) sensing elements for measuring electrocardiogram (ECG), thoracic bio-impedance (TBI), photoplethysmogram (PPG), and phonocardiogram (PCG) waveforms； ii) a processor for collectively analyzing the ECG, TBI, PPG, and PCG waveforms to determine a set of physiological parameters； and iii) a first wireless transceiver configured to transmit the set of physiological parameters； 2) a gateway system comprising a second wireless transceiver configured to receive the set of physiological parameters； and 3) a data-analytics system configured to analyze the set of physiological parameters to determine the patient's status.
