Risk Factors for Low Levels of Parathyroid Hormone after Surgery for Thyroid Cancer: A Single Center Study

Abstract

Background: Thyroidectomy is the definitive treatment for most patients with thyroid cancer. Hypoparathyroidism is the most frequent complication of thyroidectomy, and its pathogenesis is multifactorial. The aim of this study is to evaluate the patient- and surgical-related risk factors for hypoparathyroidism after surgery for thyroid cancer. Methods: In this retrospective study, patients referred to surgery for thyroid cancer from 2016 to 2019 were enrolled. Preoperative serum calcium and parathyroid hormone (PTH) and postoperative 24 h PTH and calcium levels were evaluated. Demographic data, type of surgery, incidence of hypoparathyroidism and hypocalcemia were recorded for all the patients. Patients were divided into two groups based on post-operative PTH levels (≤12 and >12 pg/mL). Results: A total of 189 patients were enrolled in this study. There were 146 women (87.3%) and 43 men (22.7%), with a mean age of 51.3 years. A total of 79 patients (41.7%) underwent a neck dissection. A total of 59 patients (31.1%) had a postoperative PTH level < 12 pg/mL. Female sex, neck dissection, the yield of lymph node dissection and incidental parathyroidectomy were significantly associated with postoperative hypoparathyroidism. Incidental parathyroidectomy was reported in 44 (23.2%) patients and was correlated with younger age (<40 years) and neck dissection. There was no difference in the rate of post-operative hypocalcemia between patients with incidental parathyroidectomy and those without. Conclusions: Young patients undergoing neck dissection and with incidental parathyroidectomy have the highest risk of postoperative hypoparathyroidism after surgery for thyroid cancer. However, a large proportion of patients without incidental parathyroidectomy may have temporary hypocalcemia, suggesting that impaired blood supply of parathyroid glands during their identification and dissection may play a relevant role.

Iatrogenic Hypoparathyroidism Development After Thyroidectomy: A Retrospective Cohort Study

“…Our study, comprising 343 patients who underwent thyroid surgery, offers several valuable insights into the incidence and risk factors associated with postthyroidectomy hypoparathyroidism. The incidence of postsurgical hypoparathyroidism was 37.90%, which is on the higher end but within the range reported by other studies [5, 14]. Two‐thirds of the participants who developed hypoparathyroidism recovered, mainly within the first month.…”

The reality of hypoparathyroidism after thyroidectomy: which risk factors are effective? Single center study

“…Although female gender was reported as a risk factor for transient hypoparathyroidism in some studies, no correlation was found between hypoparathyroidism and gender in other studies. [ 33 - 35 ]…”

“…However, there are studies demonstrating no relationship between age and hypoparathyroidism. [ 35 - 37 ]…”

Management of Postthyroidectomy Hypoparathyroidism and Its Effect on Hypocalcemia‐Related Complications: A Meta‐Analysis

“…A total of 1743 articles were screened (Figure 1) and 237 full‐text articles were assessed for eligibility. After careful selection of the articles, 66 studies were eligible for the final synthesis and were included in this review 10,14,23,24,27‐88 …”