Efficacy of Intracordal Trafermin Injection Using Propensity Score Matching in Age-Related Vocal Fold Atrophy

We hypothesized that Intracordal Trafermin Injection (ITI) provides greater voice improvement than standard voice therapy (VT) in age-related vocal fold atrophy (ARVA). To evaluate the efficacy of ITI versus VT using propensity score matching (PSM) in ARVA.

This retrospective study was conducted at the Tokyo Voice Center between July 2014 and December 2024 using medical records in ARVA. The intervention group comprised 197 of 210 patients who received ITI (mean voice recording period: 40.98 days after injection). The control group included 412 of 488 patients who underwent voice therapy (VT) between April 2015 and December 2024 (mean voice recording period: 79.91 days after initial VT). The primary outcome was defined as the improvement in VHI, calculated as the difference between post-treatment and pre-treatment scores. PMS was used to compare ITI and VT.

Before PSM, the mean age and sex (female) were 65.30 years (standard deviation [SD], 14.01) and 48 patients (24.67%) in the ITI group and 64.81 years (SD, 14.42) and 246 patients (59.71%) in the VT group, respectively. T-tests revealed no significant differences in outcomes. After PSM (C-statistic = 0.746), the baseline characteristics were balanced (standardized mean difference < 0.1). Post-matching, t-tests revealed significantly greater voice improvement in the ITI group (p = 0.023).

ITI appears effective for improving voice outcomes in ARVA. Future studies should include prospective interventional trials and comparative analyses with other injectable agents to determine the most effective treatment.