Arterial pulse harmonic alterations: a novel biomarker linking vascular dysfunction to prefrailty

Area of Science:

• Gerontology and Cardiovascular Health
• Biomarker Discovery
• Noninvasive Diagnostic Techniques

Background:

• Pre-frailty, a reversible state of vulnerability in older adults, presents a diagnostic challenge.
• Arterial stiffness, a marker of vascular aging, is linked to frailty, suggesting shared underlying mechanisms.
• Early vascular dysfunction in prefrailty warrants investigation using arterial pulse signals.

Purpose of the Study:

• To determine if spectral pulse analysis can identify objective biomarkers for prefrailty.
• To explore the relationship between arterial pulse waveform characteristics and prefrailty status.

Main Methods:

• Analysis of 1-minute radial pulse signals from 112 older adults (49 prefrail, 63 robust).
• Extraction of 40 harmonic indices from pulse signals.
• Evaluation using conventional machine learning (ML) and pulse-distribution analysis (PDA).

Main Results:

• Pre-frail individuals exhibited altered pulse waveforms with reduced amplitude proportions and increased variability.
• Conventional ML models showed limited discrimination (AUC ≤0.63).
• Pulse-distribution analysis (PDA) achieved significant discrimination (AUC = 0.70), consistent across subgroups and minimally affected by confounding factors.

Conclusions:

• A novel pulse-derived harmonic signature serves as a biomarker for prefrailty.
• Spectral analysis detects subtle arterial functional alterations linked to early physical vulnerability.
• The noninvasive 1-minute protocol offers a clinically feasible method for early identification of high-risk older adults.