Swallowing disorders after thyroidectomy: a systematic review and meta-analysis

Purpose Swallowing disorders following thyroidectomy are common, even after surgery without confirmed complications. The purpose of the current systematic review is to investigate the prevalence of dysphagia at various time points after thyroidectomy, at the whole spectrum of it (total/partial, open/endoscopic, for benign/malignant disease). Methods The literature available at PubMed, SciELO and Cochrane Library databases was reviewed, according to PRISMA guidelines, using the terms "dysphagia", "swallowing disorder", "deglutition disorder", "thyroidectomy" and "thyroid surgery" in the appropriate combinations. A quantitative synthesis of the results followed. Results The systematic review of the literature resulted in 35 articles, which met the inclusion criteria and were analyzed regarding their type, sample, follow-up and results regarding post-thyroidectomy dysphagia in multiple follow-up times. A significant increase of swallowing impairment compared to baseline was recorded shortly after surgery. Dysphagia reverted to pre-operative levels 2-3 months later. Dysphagia continued to be reported in a significantly lower proportion of patients, even 1 year after surgery. No significant difference was noticed between open and endoscopic thyroid surgery at 2-3 months post-surgery. Conclusions The swallowing disorders reported after thyroidectomy should be expected, but are not always detectable through objective methods. This should not lead to underestimation of symptoms, since the patients' quality of life is negatively affected by the symptomatology.