Pulse wave analysis for quality-of-life associated early physiological changes during breast cancer chemotherapy: a proof-of-concept pilot study

BACKGROUND: Breast cancer (BC) treatment, while essential, often impairs quality of life (QoL), typically assessed through -subjective reports. This single‑center, proof‑of‑concept observational study aimed to develop an objective and noninvasive monitoring method based on spectral analysis of the arterial blood pulse waveform (BPW). We investigated whether specific harmonic indices derived from the BPW could track physiological changes in BC patients following chemotherapy and correlate with patient-reported QoL improvements. METHODS: Radial BPW signals were measured noninvasively in 41 BC patients before and after treatment, deriving harmonic indices including amplitude proportion and phase angle. QoL was assessed using the EORTC QLQ-C30 questionnaire. The pulse-distribution analysis (PDA) scoring model was used to classify patients based on their degree of improvement in Global-Health-Status scores. RESULTS: Results showed significant post-chemotherapy decreases in specific harmonic indices, suggesting normalized vascular dynamics. The PDA scoring model effectively classified patients by their Global-Health-Status improvement, achieving an AUC of 0.87 for extreme groups. PDA effect scores demonstrated a significant positive correlation with QoL changes (R = 0.332), outperforming heart rate and its variability. Notably, subgroup analysis revealed this correlation was substantially stronger in early-stage patients (Stage I: R = 0.787). Crucially, PDA scores were not confounded by age. CONCLUSION: This exploratory study suggests that the pulse‑wave‑based approach may serve as a low-cost, portable tool for monitoring early physiological changes in BC patients, potentially complementing traditional subjective QoL assessments in clinical practice. The enhanced sensitivity observed in early‑stage disease warrants further investigation. These proof‑of‑concept findings are hypothesis‑generating and require validation in larger prospective studies.