Beyond the Nerves: Thyroid Autoimmunity as a Non-Neural Factor for Post-Thyroidectomy Dysphonia

This study aims to investigate the impact of elevated preoperative thyroid autoantibodies, a proposed non-neural contributor, on postoperative voice outcomes, specifically within a cohort of patients undergoing nerve-preserved thyroidectomy verified by intraoperative neuromonitoring (IONM).

A retrospective analysis included 212 patients who underwent primary nerve-preserved thyroidectomy with IONM-confirmed integrity of recurrent and superior laryngeal nerves. Patients were categorized into elevated antibody (EA) and normal antibody (NA) groups according to thyroglobulin antibody (TgAb) and anti-thyroid microsomal antibody (TMAb) levels. Objective and subjective voice analyzes (VHI, VRQoL, and IVST) were performed pre- and postoperatively.

The EA group had a significantly higher proportion of bilateral surgeries, larger tumors, and heavier specimens. Several postoperative voice parameters differed significantly between the two groups, and after adjustment for patient characteristics, EA levels remained independently associated with abnormal shimmer (adjusted OR 2.33, p = 0.021) and abnormal IVST-T (adjusted OR 2.72, p = 0.010). In the antibody-grade analysis, a preliminary non-linear pattern between antibody burden and postoperative voice outcomes was observed in shimmer, IVST-T, and IVST-S.

In this retrospective exploratory study, elevated thyroid autoantibodies were associated with poorer objective voice stability and greater subjective voice impairment following IONM-verified nerve-preserved thyroidectomy. With standardized IONM minimizing the influence of major neural injury, these findings highlight a potential non-neural influence of thyroiditis on postoperative dysphonia. Shimmer and IVST are useful indicators for detecting subtle functional changes, supporting thyroid antibody status as a practical serological indicator for individualized perioperative counseling and rehabilitation.

Level III.