Stratified Therapeutic Evaluation of Presbyphonia Based on Degree of Vocal Fold Atrophy: Efficacy and Prognostic Differences of Semi-Occluded Vocal Tract Training Across Different Stages.

OBJECTIVE

This study aimed to evaluate the stratified therapeutic effects of semi-occluded vocal tract (SOVT) training based on the degree of vocal fold atrophy and to explore response trajectories.

METHODS

In this single-center prospective cohort study, 180 patients with presbyphonia were stratified into mild, moderate, and severe groups. All participants received standardized SOVT training and were followed for 8 weeks. The primary outcome was change in VHI-10. Secondary outcomes included GRBAS, maximum phonation time (MPT), cepstral peak prominence (CPP), acoustic perturbation parameters (jitter, shimmer, PPQ, APQ, and NHR), and glottal gap score. Linear mixed-effects models and latent class growth analysis (LCGA) were applied. Time effects referred to repeated measurements obtained at baseline, Week 4, and Week 8.

RESULTS

Significant overall improvements were observed in VHI-10, MPT, and CPP (all p < 0.001). Additional acoustic perturbation and noise-related parameters, including jitter, shimmer, PPQ, APQ, and NHR, also improved significantly over time (all p < 0.001). A significant time × severity interaction was found for VHI-10 (p < 0.001), with the moderate group demonstrating the greatest improvement. Overall, 68.9% achieved the minimal clinically important difference (MCID) threshold. LCGA identified three response trajectories, with moderate cases more likely to show rapid or sustained improvement.

CONCLUSIONS

SOVT training is effective for presbyphonia, with therapeutic response varying according to the severity of vocal fold atrophy. Both cepstral and perturbation-based acoustic analyses supported progressive improvement after intervention. Patients with moderate vocal fold atrophy appeared to derive the greatest therapeutic benefit, suggesting a potential optimal therapeutic window for intervention. Stratified assessment and trajectory-based analysis may facilitate individualized voice rehabilitation strategies.