Post-thyroidectomy voice and swallowing disorders and association with laryngopharyngeal reflux: A scoping review.

Objective: Postthyroidectomy voice and swallowing symptoms (PVSS) may occur even in absence of laryngeal nerve injuries, which remains poorly understood. The objective of this review was to investigate the occurrence of PVSS and the potential etiological role of laryngopharyngeal reflux (LPR). Design: Scoping review. Methods: Three investigators search PubMed, Cochrane Library, and Scopus databases for studies investigating the relationship between reflux and PVSS. The authors adhered to PRISMA statements and the following outcomes were investigated: age, gender, thyroid features, reflux diagnosis, association outcomes, and treatment outcomes. Based on the study findings and bias analysis, authors proposed recommendations for future studies. Results: Eleven studies met our inclusion criteria, accounting for 3829 patients (2964 females). Postthyroidectomy swallowing and voice disorders were found in 5.5%-64%; and 16%-42% of patients, respectively. Prospectively, some results suggested an improvement of swallowing/voice disorders postthyroidectomy, whereas others did not observe significant changes. The prevalence of reflux ranged from 16.6% to 25% of subjects who benefited from thyroidectomy. There was an important heterogeneity between studies regarding the profile of included patients, the PVSS outcomes used, the delay of PVSS assessment and reflux diagnosis, making difficult the study comparison. Some recommendations were provided to guide future studies, especially about the reflux diagnosis approach and clinical outcomes. Conclusion: The potential etiological role of LPR in PVSS is not demonstrated. Future studies are needed to demonstrate an increase of pharyngeal reflux events with objective findings from prethyroidectomy to postthyroidectomy. Level of Evidence: 3a.