Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis
Juan J Díez 1 2 , Emma Anda 3 , Julia Sastre 4 , Begoña Pérez Corral 5 , Cristina Álvarez-Escolá 6 , Laura Manjón 7 , Miguel Paja 8 , Marcel Sambo 9 , Piedad Santiago Fernández 10 , Concepción Blanco Carrera 11 , Juan C Galofré 12 , Elena Navarro 13 , Carles Zafón 14 , Eva Sanz 14 , Amelia Oleaga 8 , Orosia Bandrés 15 , Sergio Donnay 16 , Ana Megía 17 , María Picallo 9 , Cecilia Sánchez Ragnarsson 7 , Gloria Baena-Nieto 18 , José Carlos Fernández García 19 , Beatriz Lecumberri 6 , Manel Sahún de la Vega 20 , Ana R Romero-Lluch 13 , Pedro Iglesias 21 22
The prevalence of postoperative hypoparathyroidism has been studied in registries and in surgical series with highly variable and imprecise results. However, the frequency of this hormonal deficiency in the clinical practice of endocrinologists is not known with accuracy. We aimed to assess the prevalence and risk factors of hypoparathyroidism in patients undergoing total thyroidectomy in Spain.
We designed a retrospective, multicentre and nation-wide protocol including all patients with total thyroidectomy who were seen in the endocrinology clinic of the participant centers from January to March 2018. Prevalence of hypoparathyroidism was evaluated at discharge of surgery, 3-6 months after surgery, 12 months after surgery and at last visit. Twenty hospitals participated in the study.
Of 1792 patients undergoing total thyroidectomy, 866 (48.3%) developed postoperative hypoparathyroidism at discharge of surgery. Most of them recover parathyroid function over time. Prevalence of hypoparathyroidism at 3-6 months, 12 months and at last visit was 22.9%, 16.7% and 14.5%, respectively. The risk of developing definitive hypoparathyroidism was related to the presence of parathyroid tissue at histology, lymph node dissection, and two-stage thyroidectomy. Patients with thyroid cancer, with higher postoperative calcium levels and treated by expert surgical teams exhibited lower risk of developing permanent hypoparathyroidism.
Although most patients with postsurgical hypoparathyroidism recover parathyroid function, the prevalence of permanent disease in clinical practice is non negligible (14.5%). Postoperative calcium, extent and timing of surgery, the presence of cancer, expert surgical team, and parathyroid tissue at histology are predictors of permanent hypoparathyroidism.