Harmonic analysis of radial pulse in traditional Chinese medicine: physiological alterations associated with hepatitis B and hepatitis C infections

Background This study investigated whether harmonic analysis (HA) of radial pressure pulse (RPP) signals, a quantitative approach derived from traditional Chinese pulse diagnosis, is associated with physiological alterations in patients with hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. Methods A total of 75 participants were enrolled, including 36 healthy controls, 17 patients with HBV infection, and 22 patients with HCV infection. Radial pressure pulse signals were acquired using the Skylark Pulse Analysis System, and harmonic components were calculated from the six radial pulse positions (left and right Cun, Guan, and Chi) following peak alignment and frequency-domain decomposition. Results Among the harmonic parameters, the first harmonic component (C1) demonstrated significant differences among the three groups (one-way analysis of variance [ANOVA], p = 0.014). Post hoc analysis revealed significantly higher C1 values in the HCV group compared with healthy controls (529.09 ± 57.99 vs. 477.78 ± 100.49, p = 0.047), whereas the HBV group showed a similar but non-significant trend (503.65 ± 64.51 vs. 477.78 ± 100.49, p = 0.481). No significant difference was observed between the HBV and HCV groups ( p = 0.098). Exploratory logistic regression analysis further demonstrated an independent association between C1 and HCV infection status (OR = 1.008, 95% CI: 1.000–1.017, p = 0.047), whereas no significant association was identified for HBV infection. Conclusion Alterations in the first harmonic component (C1) of radial pulse waveforms were observed in patients with chronic viral hepatitis, particularly in those with HCV infection. These findings suggest that harmonic analysis may provide complementary information regarding systemic physiological alterations associated with viral hepatitis. However, the exploratory nature of this study, together with the small sample size and modest effect size, warrants cautious interpretation. Larger prospective studies are needed to validate these observations and clarify their clinical significance.