Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis

Risk factors of transient and permanent hypoparathyroidism after thyroidectomy: a systematic review and meta-analysis

BACKGROUND

Postoperative hypoparathyroidism (hypoPT) is a common complication following thyroid surgery. However, current research findings on the risk factors for post-thyroid surgery hypoPT are not entirely consistent, and the same risk factors may have different impacts on transient and permanent hypoPT. Therefore, there is a need for a comprehensive study to summarize and explore the risk factors for both transient and permanent hypoPT after thyroid surgery.

MATERIALS AND METHODS

Two databases (PubMed and Embase) were searched from inception to 2024. The Newcastle-Ottawa Scale was used to rate study quality. Pooled odds ratios were used to calculate the relationship of each risk factor with transient and permanent hypoPT. Subgroup analyses were conducted for hypoPT with different definition-time (6 or 12 months). Publication bias was assessed using Begg's test and Egger's test.

RESULTS

A total of 19 risk factors from the 93 studies were included in the analysis. Among them, sex and parathyroid autotransplantation were the most frequently reported risk factors. Meta-analysis demonstrated that sex (female vs. male), cN stage, central neck dissection, lateral neck dissection, extent of central neck dissection (bilateral vs. unilateral), surgery [total thyroidectomy (TT) vs. lobectomy], surgery type (TT vs. sub-TT), incidental parathyroidectomy, and pathology (cancer vs. benign) were significantly associated with transient and permanent hypoPT. Preoperative calcium and parathyroid autotransplantation were only identified as risk factors for transient hypoPT, while preoperative PTH was a protective factor. Additionally, node metastasis and parathyroid in specimen were associated with permanent hypoPT.

CONCLUSION

The highest risk of hypoPT occurs in female thyroid cancer patients with lymph node metastasis undergoing TT combined with neck dissection. The key to preventing postoperative hypoPT lies in the selection of surgical approach and intraoperative protection.

Early hospital discharge through prediction of post-thyroidectomy hypoparathyroidism

INTRODUCTION

Hypoparathyroidism is the most common postsurgical complication of total thyroidectomy. Furthermore, it is the main cause of prolonged hospitalisation after this procedure.

OBJECTIVE

To predict the probability of post-thyroidectomy hypocalcaemia according to the levels of intact parathyroid hormone (iPTH), as well as to determine the needs for treatment with exogenous calcium according to the levels of serum calcium (Ca).

MATERIALS AND METHODS

Retrospective study was carried out on patients who underwent total thyroidectomy between January 2017 and January 2020 at Los Arcos del Mar Menor University Hospital (HULAMM). iPTH and Ca levels ​​were measured at 4, 24 and 48 h after the surgery. Follow-up was 6 months.

RESULTS

Ninety-four patients were operated on. Temporary and permanent postoperative hypoparathyroidism percentages were, respectively, 51.06% and 6.38%. iPTH level 24 h after the procedure was the most reliable predictor of post-thyroidectomy temporary hypoparathyroidism (Area Under the ROC Curve (AUC) = 0.933, p < .001). iPTH levels ​​≥29 pg/mL predicted normal parathyroid metabolism.

CONCLUSIONS

The combined values of iPTH and Ca levels 24 h after thyroidectomy seems to be a reliable, safe and efficient method to control the post-thyroidectomy hypoparathyroidism. Our protocol could reduce the hospital stay of patients at low risk of hypocalcaemia, allowing them to be discharged from the hospital on the first postoperative morning and identifying patients at high risk of hypocalcaemia early.

Disease-free survival and response to therapy of clinically node- negative Papillary Thyroid Cancer treated without central neck dissection: Retrospective study of 321 patients

BACKGROUND AND OBJECTIVE

Nodal metastases in the central compartment are frequent in papillary thyroid cancer (PTC). However, they are mostly micrometastases with no impact on survival and their relevance on the risk of locoregional relapse is controversial. There is no consensus regarding optimal management of the central neck in patients with PTC cN0. In our center, we do not perform prophylactic central neck dissection (pCND). The objective of this study is to review our long-term results and compare them with the most recent literature.

PATIENTS AND METHODS

Retrospective review of patients with PTC who underwent total thyroidectomy (TT) without CND between 2005 and 2017. Primary result was disease-free survival in the neck (DFS).

RESULTS

321 patients were identified, mostly T1-T2 tumors (94.1%). Median follow-up was 90 months. DFS in the central compartment was excellent (96.1% at 10 year's follow-up). 19 patients had cervical recurrence, of which 15 underwent salvage surgery. On their last visit, including salvage surgery when appropriate, 77% of patients had excellent response, 18.7% had indeterminate response, 3.1% had biochemically incomplete response and 1.2% had morphologically incomplete response. Recurrent laryngeal nerve (RLN) paralysis after TT was transient in 4.7% of patients and permanent in 0.9% of patients. There were no RLN paralysis after salvage surgery. Permanent hypoparathyroidism occurred in 3.4% of patients. Only one patient had hypoparathyroidism after salvage surgery and it was permanent.

CONCLUSIONS

Based on long-term results and low rate of complications associated with salvage surgery in our experience, we consider routine pCND is not justified.

Early parathyroid hormone (PTH) level as a predictor of post-surgical hypoparathyroidism

INTRODUCTION

Post-operative hypocalcemia and postoperative persistent hypoparathyroidism remain the most common complications after thyroidectomy. Many approaches have been developed to prevent them, but actually, a common protocol is not yet individuated.

MATERIALS AND METHODS

We retrospectively analyzed the results of a prospectively collected database. We dosed PTH preoperatively and 4 h after surgery (PTH_4); calcium was evaluated preoperatively, on the first (I_POD) and on the second postoperative day (II_POD). Hypocalcemia was defined when calcium <8 mg/dl. PTH_4 and I_POD calcium serum levels are identified to predict postoperative hypocalcemia.

RESULTS

Three hundred and forty-eight patients were enrolled, 37 patients resulted as hypocalcemic on I_POD and 41 on the II_POD. PTH_4 is related to I_POD (p < 0.001, r = 0.45) and II_POD (p < 0.001, r = 0.44) calcemia. PTH_4-cut-off predicting I_POD hypocalcemia was 10.50 pg/ml (sensitivity: 78.7%, specificity: 72.7%). A PTH_4 value of 11.5 pg/ml is able to predict hypocalcemia during II_POD (sensitivity: 76.5%, specificity: 69.2%). We set up a combined test to predict II_POD hypocalcemia, using PTH_4 and I_POD calcium (sensitivity: 77.8%, specificity: 89.9%).

CONCLUSION

This research shows the association between PTH_4 and postoperative hypocalcemia. The PTH_4 cut-off to predict I_POD-hypocalcemia was 10.5 pg/ml. We analyzed the calcemia trend during the postoperative period and we realized a combined test using PTH_4 and I_POD-calcemia. This test improves the accuracy of the previous test. Further studies, in particular multicentric, with a larger sample are necessary to validate the combined model.

Incident comorbidities in patients with chronic hypoparathyroidism after thyroidectomy: a multicenter nationwide study

Purpose

Population-based and registry studies have shown that chronic hypoparathyroidism is accompanied by long-term complications. We aimed to evaluate the risk of incident comorbidity among patients with chronic postsurgical hypoparathyroidism in real-life clinical practice in Spain.

Methods

We performed a multicenter, retrospective cohort study including patients with chronic postsurgical hypoparathyroidism lasting ≥3 years with at least a follow-up visit between January 1, 2022 and September 15, 2023 (group H). The prevalence and incidence of chronic complications including chronic kidney disease, nephrolithiasis/nephrocalcinosis, hypertension, dyslipidemia, diabetes, cardiovascular disease, central nervous system disease, mental health disorders, eye disorders, bone mineral density alterations, fracture and cancer were evaluated. Patient data were compared with a group of patients who did not develop hypoparathyroidism, matched by gender, age, and follow-up time after thyroidectomy (group NH).

Results

We included 337 patients in group H (median [IQR] age, 45 [36-56] years; median time of follow-up, 8.9 [6.0-13.0] years; women, 84.3%) and 669 in group NH (median age, 47 [37-55] years; median time of follow-up, 8.0 [5.3-12.0] years; women, 84.9%). No significant differences were found in the prevalence of comorbidities at the time of thyroidectomy between both groups. In multivariable adjusted analysis, patients with chronic hypoparathyroidism had significantly higher risk of incident chronic kidney disease (OR, 3.45; 95% CI, 1.72-6.91; P<0.001), nephrolithiasis (OR, 3.34; 95% CI, 1.55-7.22; P=0.002), and cardiovascular disease (OR, 2.03; 95% CI, 1.14-3.60; P=0.016), compared with patients without hypoparathyroidism. On the contrary, the risk of fracture was decreased in patients with hypoparathyroidism (OR, 0.09; 95% CI, 0.01-0.70; P=0.021).

Conclusion

This study demonstrates that, in the clinical practice of Spanish endocrinologists, a significant increase in the risk of chronic kidney disease, nephrolithiasis and cardiovascular disease, as well as a reduction in the risk of fractures is detected. These results are of interest for the development of new clinical guidelines and monitoring protocols for patients with hypoparathyroidism.

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

OBJECTIVE

The aim of this Meta-analysis is to evaluate the impact of different treatment strategies for early postoperative hypoparathyroidism on hypocalcemia-related complications and long-term hypoparathyroidism.

DATA SOURCES

Embase.com, MEDLINE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, and the top 100 references of Google Scholar were searched to September 20, 2022.

REVIEW METHODS

Articles reporting on adult patients who underwent total thyroidectomy which specified a treatment strategy for postthyroidectomy hypoparathyroidism were included. Random effect models were applied to obtain pooled proportions and 95% confidence intervals. Primary outcome was the occurrence of major hypocalcemia-related complications. Secondary outcome was long-term hypoparathyroidism.

RESULTS

Sixty-six studies comprising 67 treatment protocols and 51,096 patients were included in this Meta-analysis. In 8 protocols (3806 patients), routine calcium and/or active vitamin D medication was given to all patients directly after thyroidectomy. In 49 protocols (44,012 patients), calcium and/or active vitamin D medication was only given to patients with biochemically proven postthyroidectomy hypoparathyroidism. In 10 protocols (3278 patients), calcium and/or active vitamin D supplementation was only initiated in case of clinical symptoms of hypocalcemia. No patient had a major complication due to postoperative hypocalcemia. The pooled proportion of long-term hypoparathyroidism was 2.4% (95% confidence interval, 1.9-3.0). There was no significant difference in the incidence of long-term hypoparathyroidism between the 3 supplementation groups.

CONCLUSIONS

All treatment strategies for postoperative hypocalcemia prevent major complications of hypocalcemia. The early postoperative treatment protocol for postthyroidectomy hypoparathyroidism does not seem to influence recovery of parathyroid function in the long term.

Surgical management of low-risk papillary thyroid cancer in real life in Spain: a nationwide survey of endocrine neck surgeons and endocrinologists

BACKGROUND

The extent of surgery in patients with papillary thyroid cancer (PTC) is a subject of ongoing debate. We aimed to explore the attitude of Spanish specialists (endocrinologists, surgeons, and otolaryngologists) in real life on the surgical management of low-risk PTC.

METHODS

We designed an anonymous, web-based survey to inquire information regarding the preferences of interviewees for hemithyroidectomy (Hem), total thyroidectomy (TT) and prophylactic central neck dissection (pCND) in one standard patient with PTC and six clinical variants. We differentiated between small (1.1-2.5 cm) and large (2.6-4.0 cm) tumors.

RESULTS

A total of 278 valid responses were received and divided into two groups: group END (n = 135) and group SUR (n = 143, 101 general surgeons and 42 otolaryngologists). The preference for Hem was low in the standard patient and similar between both groups (40.6 vs 49.0%, NS). This preference decreased for tumors measuring 2.6-4.0 cm, multifocal, with risk location, family history of thyroid cancer, or history of irradiation, and increased in patients older than 65 years or with comorbidity. Preference for pCND ranged from 12.6-71.1% in the group END and from 22.4-65.0% in the group SUR, with few differences between the two. In multivariate analysis, being a high-volume specialist was associated with a lower preference for Hem, while having private practice was associated with a more favorable opinion of Hem.

CONCLUSION

The real clinical practice of Spanish specialists is far from what is recommended by the clinical guidelines in patients with low-risk PTC, especially among high-volume professionals.

Regional Collaboration and Trends in Clinical Management of Thyroid Cancer

OBJECTIVE

This study examines the trends in the management of thyroid cancer and clinical outcomes in the Southwestern region of The Netherlands from 2010 to 2021, where a regional collaborative network has been implemented in January 2016.

STUDY DESIGN

Retrospective cohort study.

SETTING

This study encompasses all patients diagnosed with thyroid cancer of any subtype between January 2010 and June 2021 in 10 collaborating hospitals in the Southwestern region of The Netherlands.

METHODS

The primary outcome of this study was the occurrence of postoperative complications. Secondary outcomes were trends in surgical management, centralization, and waiting times of patients with thyroid cancer.

RESULTS

This study included 1186 patients with thyroid cancer. Median follow-up was 58 [interquartile range: 24-95] months. Surgery was performed in 1027 (86.6%) patients. No differences in postoperative complications, such as long-term hypoparathyroidism, permanent recurrent nerve paresis, or reoperation due to bleeding were seen over time. The percentage of patients with low-risk papillary thyroid carcinoma referred to the academic hospital decreased from 85% (n = 120/142) in 2010 to 2013 to 70% (n = 120/171) in 2014 to 2017 and 62% (n = 100/162) in 2018 to 2021 (P < .01). The percentage of patients undergoing a hemithyroidectomy alone was 9% (n = 28/323) in 2010 to 2013 and increased to 20% (n = 63/317; P < .01) in 2018 to 2021.

CONCLUSION

The establishment of a regional oncological network coincided with a de-escalation of thyroid cancer treatment and centralization of complex patients and interventions. However, no differences in postoperative complications over time were observed. Determining the impact of regional oncological networks on quality of care is challenging in the absence of uniform quality indicators.

Impact of autofluorescence for detection of parathyroid glands during thyroidectomy on postoperative parathyroid hormone levels: parallel multicentre randomized clinical trial

BACKGROUND

Techniques for autofluorescence have been introduced to visualize the parathyroid glands during surgery and to reduce hypoparathyroidism after thyroidectomy.

METHODS

This parallel multicentre RCT investigated the use of Fluobeam® LX to visualize the parathyroid glands by autofluorescence during total thyroidectomy compared with no use. There was no restriction on the indication for surgery. Patients were randomized 1 : 1 and were blinded to the group allocation. The hypothesis was that autofluorescence enables identification and protection of the parathyroid glands during thyroidectomy. The primary endpoint was the rate of low parathyroid hormone (PTH) levels the day after surgery.

RESULTS

Some 535 patients were randomized, and 486 patients received an intervention according to the study protocol, 246 in the Fluobeam® LX group and 240 in the control group. Some 64 patients (26.0 per cent) in the Fluobeam® LX group and 77 (32.1 per cent) in the control group had low levels of PTH after thyroidectomy (P = 0.141; relative risk (RR) 0.81, 95 per cent c.i. 0.61 to 1.07). Subanalysis of 174 patients undergoing central lymph node clearance showed that 15 of 82 (18 per cent) in the Fluobeam® LX group and 31 of 92 (33 per cent) in the control group had low levels of PTH on postoperative day 1 (P = 0.021; RR 0.54, 0.31 to 0.93). More parathyroid glands were identified during operation in patients who had surgery with Fluobeam® LX, and fewer parathyroid glands in the surgical specimen on definitive histopathology. No specific harm related to the use of Fluobeam® LX was reported.

CONCLUSION

The use of autofluorescence during thyroidectomy did not reduce the rate of low PTH levels on postoperative day 1 in the whole group of patients. It did, however, reduce the rate in a subgroup of patients. Registration number: NCT04509011 (http://www.clinicaltrials.gov).

Intraoperative prevention of postoperative hypoparathyroidism

Objective

More than 30,000 thyroid surgeries are performed annually in the Russian Federation. The surgeries are relatively safe because of the prevention methods for postoperative complications. Currently, there is no single effective method of postoperative hypoparathyroidism prevention. This complication is frequently reported and may be health and life-threatening.

Aim

We aimed to estimate the effectiveness of the intraoperative ICG-angiography and intrathyroid injection of Brilliant Green for the prevention of postoperative hypoparathyroidism.

Material and methods

One hundred and forty-three thyroidectomies were performed. Patients were divided into three groups: intraoperative angiography was used in 24 cases; Brilliant Green was injected in 58 cases to identify parathyroid glands; the visual estimation of the parathyroid preservation was used in 61 cases. Calcium level was measured in all patients before and after surgery.

Results

Calcium level in the serum before and after surgery was 2.37±0.14 and 2.27±0.17 in Group 1, 2.38±0.16 and 2.21±0.16 in Group 2, and 2.39±0.17 and 2.18±0.19 in Group 3. Postoperative hypocalcemia was more prominent in the group with the visually estimated PTG than in the two other groups. The differences in postoperative calcium levels in Groups 1 and 3 were statistically different. Pre- and postoperative Parathormone levels were 6.2±0.4 in Group 1, 5.6±0.57 in Group 2, and 3.5±0.32 in Group 3. Postoperative levels significantly differed in Groups 1 and 3 (p<0.01) and in Groups 2 and 3 (p<0.05).

Conclusions

ICG-angiography and intrathyroid injection of the Brilliant Green are safe methods of identification and sparing of the parathyroid glands. The severity of hypocalcemia and hypoparathormonemia in Group 3 shows the necessity of finding new methods in endocrine surgery to improve patient outcomes.

Role of prophylactic central neck lymph node dissection for papillary thyroid carcinoma in the era of de-escalation

Thyroid cancer is the most common endocrine malignancy. While there has been no appreciable increase in the observed mortality of well-differentiated thyroid cancer, there has been an overall rise in its incidence worldwide over the last few decades. Patients with papillary thyroid carcinoma (PTC) and clinical evidence of central (cN1) and/or lateral lymph node metastases require total thyroidectomy plus central and/or lateral neck dissection as the initial surgical treatment. Nodal status in PTC patients plays a crucial role in the prognostic evaluation of the recurrence risk. The 2015 guidelines of the American Thyroid Association (ATA) have more accurately determined the indications for therapeutic central and lateral lymph node dissection. However, prophylactic central neck lymph node dissection (pCND) in negative lymph node (cN0) PTC patients is controversial, as the 2009 ATA guidelines recommended that CND "should be considered" routinely in patients who underwent total thyroidectomy for PTC. Although the current guidelines show clear indications for therapeutic CND, the role of pCND in cN0 patients with PTC is still debated. In small solitary papillary carcinoma (T1, T2), pCND is not recommended unless there are high-risk prediction factors for recurrence and diffuse nodal spread (extrathyroid extension, mutation in the BRAF gene). pCND can be considered in cN0 disease with advanced primary tumors (T3 or T4) or clinical lateral neck disease (cN1b) or for staging and treatment planning purposes. The role of the preoperative evaluation is fund-amental to minimizing the possible detrimental effect of overtreatment of the types of patients who are associated with low disease-related morbidity and mortality. On the other hand, it determines the choice of appropriate treatment and determines if close monitoring of patients at a higher risk is needed. Thus, pCND is currently recommended for T3 and T4 tumors but not for T1 and T2 tumors without high-risk prediction factors of recurrence.

Effect of intraoperative active exploration of parathyroid glands to reduce the incidence of postoperative hypoparathyroidism, and risk factors of hypoparathyroidism after total thyroidectomy: a single-center study

Background

The risk factors for hypoparathyroidism after thyroid surgery have not been fully identified. This study analyzes the risk factors of hypoparathyroidism before and after total thyroidectomy.

Methods

We retrospectively collected the clinical data of 289 patients who underwent total thyroidectomy at the Thyroid Surgery Center of Lishui Central Hospital from June 2018 to June 2020. For the anatomy and protection of parathyroid glands during the operation, one group of patients used the parathyroid avoidance method, and the other group used the active exploration method. Various risk factors affecting parathyroid dysfunction were studied using logistic regression models.

Results

A total of 289 patients were included in this study. The average age of patients was 47.21 ± 11.78 years, including 57 males (19.7%) and 232 females (80.3%). There were 149 (51.6%) patients with transient hypoparathyroidism and 21 (7.3%) with permanent hypoparathyroidism. The main risk factors of hypoparathyroidism were parathyroid avoidance method (P = 0.005), parathyroid autotransplantation (P = 0.011), bilateral central neck lymph node dissection (CND) (P = 0.001), lymphatic metastasis (P = 0.039), and parathyroid in the specimen (P = 0.029). The main risk factors associated with permanent hypoparathyroidism were bilateral CND (P = 0.038), lymphatic metastasis (P = 0.047), parathyroid hormone (PTH) < 1.2 pg/ml within three days after surgery (P = 0.006).

Conclusion

Hypoparathyroidism is common but mostly transient after bilateral total thyroidectomy. Compared with parathyroid avoidance method, the active exploration method during operation may reduce the incidence of postoperative hypoparathyroidism. PTH <1.2 pg/ml within three days after surgery was predictive in patients with permanent hypoparathyroidism.

Safe thyroid surgery: comparison effectiveness of ICG angiography and intrathyroidal brilliant green injection for the prevention of postoperative hypoparathyroidism

BACKGROUND: More than 30,000 surgical interventions on the thyroid gland are performed annually in the Russian Federation. Surgeons are developing methods for the prevention of various postoperative complications, and therefore operations on this organ are considered relatively safe. Currently, there is no unequivocal effective method to prevent postoperative hypoparathyroidism. This complication is often recorded and can threaten the life and health of the patient, which is contrary to the concept of safe surgery.

AIM: To evaluate the effectiveness of intraoperative ICG angiography and intrathyroidal injection of brilliant green for the prevention of postoperative hypoparathyroidism.

MATERIALS AND METHODS: 143 thyroidectomies were performed. The patients were divided into 3 groups: intraoperative angiography was used in 24 cases, brilliant green was injected to identify the parathyroid glands in 58 cases, visual assessment of the preservation of the parathyroid glands was used in 61 case. Calcium levels were measured in all patients included in the study before and after surgery.

RESULTS: Serum calcium levels in the pre- and postoperative period: 2.37±0.14 and 2.27±0.17 in group 1, and 2.38±0.16 and 2.21±0.16 in group 2, 2.39±0.17 and 2.18±0.19 in group 3. Hypocalcemia in the postoperative period was significantly higher in the group with a visual assessment of the parathyroid glands relative to the first two groups. Differences between calcium levels in the postoperative period in groups 2 and 3 were significant with a probability of more than 99% (p<0.01). Significant differences (≥95%) in calcium levels in the postoperative period between groups 1 and 2 (p < 0.05) were obtained. Serum PTH levels in the postoperative period: 6,2±0,4 in group 1, 5,6±0,57 in group 2, 3,5±0,32 in group 3. Differences between PTH levels in the postoperative period in groups 1 and 3 were significant with a probability of more than 99% (p<0.01). Significant differences (≥95%) in PTH levels in the postoperative period between groups 2 and 3 (p < 0.05) were obtained.

CONCLUSION: ICG angiography and brilliant green intrathyroidal injection are safe methods for identifying and preserving the parathyroid glands. The high level of hypocalcemia in group 3 indicates the need to search for new techniques in endocrine surgery in order to improve the safety of patients undergoing surgical treatment of thyroid pathology.

Epidemiology and Financial Burden of Adult Chronic Hypoparathyroidism

Chronic hypoparathyroidism is characterized by low serum calcium, increased serum phosphorus, and inappropriately low or decreased serum parathyroid hormone. This rare disorder is associated with a variety of complications. The prevalence, incidence, mortality, financial burden, and epidemiology of complications of this disorder are not well understood. This narrative review summarizes current information on the epidemiology and complications of chronic hypoparathyroidism. The reported prevalence of chronic hypoparathyroidism ranges from 6.4-37/100,000, and the incidence is reported to be 0.8-2.3/100,000/year. Mortality is not increased in studies from Denmark or South Korea but was increased in studies from Scotland and Sweden. The financial burden of this disorder is substantial because of increased health care resource utilization in two studies but not well quantitated. Recognized complications include hypercalciuria, nephrocalcinosis, kidney stones, and chronic kidney disease; low bone turnover and possibly upper extremity fractures; cardiac and vascular calcifications; basal ganglia calcifications, cataracts, infections, neuropsychiatric complications, and difficulties with pregnancy. This review concludes that chronic hypoparathyroidism is a rare disorder associated with significant morbidity that may not increase overall mortality but is associated with a substantial financial burden. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Etiology and Pathophysiology of Hypoparathyroidism: A Narrative Review

The approach utilized a systematic review of the medical literature executed with specifically designed criteria that focused on the etiologies and pathogenesis of hypoparathyroidism. Enhanced attention by endocrine surgeons to new knowledge about parathyroid gland viability are reviewed along with the role of intraoperative parathyroid hormone (ioPTH) monitoring during and after neck surgery. Nonsurgical etiologies account for a significant proportion of cases of hypoparathyroidism (~25%), and among them, genetic etiologies are key. Given the pervasive nature of PTH deficiency across multiple organ systems, a detailed review of the skeletal, renal, neuromuscular, and ocular complications is provided. The burden of illness on affected patients and their caregivers contributes to reduced quality of life and social costs for this chronic endocrinopathy. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Actual prevalence of hypoparathyroidism after total thyroidectomy: a health insurance claims-database study

PURPOSE

Persistent hypoparathyroidism (hypoPT) is a major complication of total thyroidectomy. Nonetheless, previous reports may have underestimated the prevalence of hypoPT due to patient selection bias. We aimed to estimate the actual prevalence of persistent hypoPT after total thyroidectomy and to find predictive factors for postoperative hypoPT.

METHODS

This study retrospectively reviewed data from a health insurance claims-based database provided by the Japan Medical Data Center Co., Ltd. From 2009 to 2019, 2388 patients who underwent total thyroidectomy were identified using the medical procedure codes. Persistent hypoPT was defined as the prescription of active vitamin D supplements for >1 year postoperatively and the assignment of hypoPT codes. The prevalence of persistent hypoPT was estimated at two different levels: minimum and maximum estimations with or without postoperative osteoporosis and/or renal failure codes. Correlates for persistent hypoPT were investigated among several demographic and clinical variables.

RESULTS

Of the 2388 patients, 1752 (73.4%) were women with a mean age of 45 years. The types of diseases were: benign thyroid disease (n = 235), malignant thyroid tumors (n = 1570), Graves ' disease (n = 558), and malignancy combined with Graves' disease (n = 25). The minimum and the maximum estimation of the prevalence of persistent hypoPT were 15.0 and 20.3%, respectively. Multivariate logistic regression analysis showed that the malignant tumor (odds ratio, 1.8) independently correlated with persistent hypoPT.

CONCLUSIONS

The prevalence of persistent hypoPT after total thyroidectomy estimated by the claims-based database was higher than previously recognized. Comprehensive attempts to preserve parathyroid function, especially in malignant diseases, are essential.

Predictors of Anxiety and Depression in Differentiated Thyroid Cancer Survivors: Results of a Cross-Sectional Study

Background: Despite an excellent survival rate, impairments are recognized in the quality of life and emotional well-being of differentiated thyroid cancer (DTC) survivors. Predictors for anxiety and depression in DTC patients are not well characterized. Objective: To identify predictors for anxiety and depression in DTC survivors. Methods: In this cross-sectional study, all DTC survivors presenting for follow-up between 2014 and 2019 in a tertiary referral hospital were asked to complete the "Hospital Anxiety and Depression Scale" (HADS). Depression (HADS-D) and anxiety (HADS-A) subscores were dichotomized for analysis. Univariate and multivariable logistic regression analyses were performed to identify predictors of anxiety and depression. Inverse probability weighting was applied to correct for bias due to nonresponse. Results: Six hundred forty patients meeting study inclusion criteria completed the HADS questionnaire (73% female, mean age 50 years). Of these, 37.6% and 15.7% of patients demonstrated HADS-A and HADS-D scores ≥8. Female sex, elevated body mass index (BMI), permanent recurrent laryngeal nerve damage (RLND), permanent hypoparathyroidism (PH), comorbidities classified in chapter XIX of the International Classification of Diseases, 10th Revision (ICD-10; external causes of morbidity and mortality), and comorbidities in chapter XXI of ICD-10 (factors influencing health status and contact with health services) were independent predictors for elevated anxiety scores with adjusted odds ratios of 1.9 ([CI 1.2-3.2], p < 0.01), 1.0 ([CI 1.0-1.1], p = 0.02), 2.6 ([CI 1.0-6.3], p = 0.04), 2.0 ([CI 1.1-3.5], p = 0.02), 5.5 ([CI 1.0-29.6], p < 0.05), and 1.7 ([CI 1.1-2.6], p = 0.03). PH, elevated anti-Tg titer, comorbidities of the digestive system (chapter XI of ICD-10), and comorbidities of the genitourinary system (chapter XIV of ICD-10) were independent predictors for depression with adjusted odds ratios of 2.2 ([CI 1.2-4.2], p = 0.01), 1.0 ([CI 1.0-1.0], p = 0.04), 3.0 ([CI 1.5-6.1], p < 0.01), and 2.4 ([CI 1.0-5.7], p = 0.04). Conclusions: Female sex, elevated BMI, RLND, PH, and comorbidities classified in chapter XIX and chapter XXI of ICD-10 are predictors for anxiety in DTC patients. PH, elevated anti-Tg titer, comorbidities of the digestive system, and comorbidities of the genitourinary system are predictors for depression in DTC patients. Physicians involved in the follow-up of DTC patients should devote particular attention to the emotional well-being in DTC patients with PH or permanent RLND.

Thyroidectomy in Australia 2022: lessons from 21,000 consecutive cases

In this article, we aim to describe our modern-day approach to total thyroidectomy, detailing the subtle refinements of our technique, as it has evolved over three decades and 21 000 cases. Since Delbridge's seminal paper in 2003, the major changes to our approach include a retrograde approach to the recurrent laryngeal nerve that allows dissection of the distal RLN from fascial bands within the ligament of Berry before medialisation of the thyroid lobe. Routine use of intraoperative nerve monitoring systems has increased our awareness of temporary neuropraxia, facilitated a reduction in the risk of bilateral RLN palsy and improved our identification and preservation of the external branch of the superior laryngeal nerve. The increasing use of advanced energy devices has been associated with a reduction in post-operative haematoma rates. We adopt a low threshold to parathyroid auto-transplantation, unless all glands are assessed to be clearly not at risk, and routinely supplement patients with Caltrate in the immediate post-operative period to minimize the risk of symptomatic hypocalcaemia. Ultimately, when we reflect on the subtle refinements that have contributed to improved outcomes, the fundamental principles of exposure and dissection that have evolved over decades remain the basis of our surgical approach and must continue to do so.

Persistent post-thyroidectomy hypoparathyroidism: A multicenter retrospective cohort study

BACKGROUND AND OBJECTIVE

The reported incidence of persistent hypoparathyroidism varies widely, and consensus on a definition is lacking. The objective was to evaluate the real-life incidence of persistent hypoparathyroidism by investigating a new pragmatic definition.

METHODS

This retrospective multicenter cohort study evaluated the effect of different definitions for persistent hypoparathyroidism on the incidence of hypoparathyroidism. In addition, risk factors for hypoparathyroidism were analyzed.

RESULTS

In total, 749 patients were included. Using the new pragmatic definition, we report an incidence of 7.9% of persistent hypoparathyroidism. When applying other commonly used definitions, incidence varied between 11.8% and 22.1%. Risk factors were parathyroid autotransplantation, presence of another surgical complication, and low postoperative serum calcium.

CONCLUSIONS

Our data show that the incidence of persistent hypoparathyroidism in the literature may vary through the use of different definitions. This study indicates that a new pragmatic definition of persistent hypoparathyroidism has the potential to enable unbiased comparison between studies.

Hypoparathyroidism after thyroidectomy: A 20-year experience at a children's hospital

INTRODUCTION

Hypoparathyroidism (HP) is the most common complication of total thyroidectomy and can be an emergency.

OBJECTIVES

To describe the prevalence of HP after total thyroidectomy in children under 14 years of age, the variables related to its appearance and its clinical expression.

PATIENTS AND METHODS

Retrospective study at a children's hospital in the last 20 years. HP was defined by the need to supplement calcium after the intervention and was considered permanent if it could not be suspended within 12 months. Fisher's statistical method of comparison of proportions.

RESULTS

Thirty-nine children and adolescents (26 females) with an age range of 3.67-14.00 years. In 25 patients, the intervention was prophylactic and in 14 it was therapeutic; 14 suffered accidental excision of some parathyroid gland, but none more than two of them; 12 presented HP, of which 3 were permanent; 5 presented clinical symptoms; 1 of them was an emergency. The frequency of HP was 4/4 when 2 parathyroids were dissected, 2/10 when one was dissected, and 6/25 when none were dissected (p = 0.02). In the prophylactic interventions, it was 6/25 compared to 6/14 in the therapeutic ones (p = 0.29). The three cases of permanent HP were in children under 6 years of age, and it did not occur in any older children (p = 0.09).

CONCLUSIONS

HP is a common and sometimes serious complication in children after total thyroidectomy. It can occur, and even be permanent, even if the intervention is prophylactic and parathyroid glands remain in situ. Younger age could be a risk factor.

Recovery of parathyroid function in patients with thyroid cancer treated by total thyroidectomy: An analysis of 685 patients with hypoparathyroidism at discharge of surgery

OBJECTIVE

We aimed to study the predictive factors for recovery of parathyroid function in hypoparathyroid patients after total thyroidectomy for thyroid cancer.

METHODS

We designed a retrospective, multicentre and nation-wide analysis of patients with total thyroidectomy who were seen in twenty endocrinology departments from January to March 2018. We selected patients with histologically proven thyroid cancer and retrieved information related to surgical procedure and thyroid cancer features. Survival analysis and Cox regression analysis were used to study the relationship between these variables and the recovery of parathyroid function.

RESULTS

From 685 patients with hypoparathyroidism at discharge of surgery, 495 (72.3%) recovered parathyroid function over time. Kaplan-Meier analysis showed that this recovery was significantly related to the presence of specialized surgical team (P<0.001), identification of parathyroid glands at surgery (P<0.001), papillary histopathology (P=0.040), and higher levels of postoperative calcium (Ca) (P<0.001) and parathyroid hormone (PTH) (P<0.001). Subjects with gross extrathyroidal extension (P=0.040), lymph node metastases (P=0.004), and surgical re-intervention after initial surgery (P=0.024) exhibited a significant risk of persistence of hypoparathyroidism. Multivariate Cox regression analysis showed that the significant and independent factors for recovery of parathyroid function were postoperative concentrations of Ca (P=0.038) and PTH (P=0.049). The presence of lymph node metastases was a negative predictor of recuperation of parathyroid function (P=0.042) in this analysis.

CONCLUSION

In patients with thyroid cancer, recovery of parathyroid function after total thyroidectomy was directly related to postoperative Ca and PTH concentrations, and inversely related to lymph node metastases.

Identification of secondary predictive factors for acute hypocalcemia following thyroidectomy in patients with low postoperative parathyroid hormone levels without overt calcium deficiency: A cohort study

BACKGROUND

The transient acute hypocalcemia (HypoCa) is the most prevalent complication after total thyroidectomy, detected primarily by subnormal intact parathyroid hormone (iPTH) and calcium levels. However, the need for calcium supplementation is ambiguous in patients who exhibit low iPTH with normal calcium levels. The aim of this study was to evaluate complementary predictors of HypoCa in this scenario.

METHODS

A retrospective cohort study with of 1597 consecutive patients undergoing total thyroidectomy, with or without neck dissection, from January 2014 to December 2018 at a single institution. Patients with an iPTH <12 pg/mL and a total calcium level ≥8 mg/dL in the first 8 h after surgery were included.

RESULTS

1597 patients identified with low postoperative iPTH without overt calcium deficiency was diagnosed. The transient HypoCa in that specific subgroup was 509 (31.9%). Multivariate analysis indicated that HYPOCA was associated with bilateral level VI neck dissection and pre- to postoperative calcium reduction >38 pg/mL. To better illustrate the model, we plotted a nomogram with the variables selected for the final model.

CONCLUSION

Total thyroidectomy patients who exhibit low postoperative iPTH levels without overt calcium deficiency should be considered for calcium replacement therapy when they a marked drop in iPTH postoperatively and underwent bilateral level VI neck dissection.

Persistent Postthyroidectomy Hypoparathyroidism in the Netherlands

Importance

Hypoparathyroidism is one of the most common complications after total or completion thyroidectomy. The reported incidence rate of hypoparathyroidism in the literature is highly variable. Data that provide a better understanding of the magnitude of this postoperative complication are warranted and can provide a stepping stone for further collaborations that aim to reduce complication rates and establish uniform treatment protocols.

Objective

To evaluate the incidence of postoperative, persistent hypoparathyroidism after total or completion thyroidectomy in patients who were referred to university hospital centers and assess the association of different definitions with the incidence of hypoparathyroidism.

Design, Setting, and Participants

This retrospective multicenter cohort study conducted throughout 2016 in 7 Dutch university hospital centers included 200 patients who were undergoing a total or completion thyroidectomy. Data analysis was conducted in January 2021.

Main Outcomes and Measures

We report on the incidence of persistent hypoparathyroidism, defined as the need for active vitamin D with or without calcium supplementation longer than 1 year after surgery.

Results

A total of 200 patients (143 women [71.5%]; mean [IQR] age, 49.0 [37.0-62.0] years) were included and 30 patients (15.0%) developed persistent hypoparathyroidism. The incidence of persistent hypoparathyroidism varied between 14.5% (calcium and active vitamin D 1 year postsurgery) to 28.5% (calcium and/or active vitamin D 6 months postsurgery) depending on the definition used.

Conclusions and Relevance

In this cohort study, the risk of persistent hypoparathyroidism after total or completion thyroidectomy was 15% in patients who were referred to university hospital centers. The high rate of persistent hypoparathyroidism warrants efforts to reduce this complication rate. There is discrepancy in the definition and treatment of persistent hypoparathyroidism, and use of uniform evidence-based treatment guidelines enables comparison of interventions.

[Prevention and treatment of postoperative hypoparathyroidism]

Hypoparathyroidism is a failure of parathyroid glands characterized by reduced serum concentration of parathyroid hormone, hypocalcemia and hyperphosphatemia. The most common cause of hypoparathyroidism is resection or damage to parathyroid glands during thyroid surgery. Postoperative hypoparathyroidism is still an urgent problem, as it requires additional treatment and prolongs hospital-stay. Considering available literature data, the authors analyze various methods of intraoperative prevention of hypoparathyroidism.

Late Recovery of Parathyroid Function After Total Thyroidectomy: A Case-Control Study

The clinical characteristics of patients with postoperative hypoparathyroidism who recover parathyroid function more than 12 months after surgery have not been studied. We aimed to evaluate whether the intensity of replacement therapy with calcium and calcitriol is related to the late recovery of parathyroid function. We compared the demographic, surgical, pathological, and analytical features of two groups of patients: cases, i. e., late recovery patients (those who recover parathyroid function>1 year after thyroidectomy, n=40), and controls, i. e., patients with permanent hypoparathyroidism (n=260). Replacement therapy with calcium and calcitriol was evaluated at discharge of surgery, 3-6 months, 12 months, and last visit. No significant differences were found in clinical, surgical, pathological, or analytical characteristics between cases and controls. The proportion of cases who required treatment with calcium plus calcitriol at 12 months was significantly lower than that found in controls (p<0.001). Furthermore, daily calcium and calcitriol doses in controls were significantly higher than those in cases at 3-6 months (p=0.014 and p=0.004, respectively) and at 12 months (p<0.001 and p=0.043, respectively). In several models of logistic regression analysis therapy with calcium and calcitriol at 12 months was negatively related to late recovery of parathyroid function. Although delayed recuperation of parathyroid function after total thyroidectomy is uncommon (13%), follow-up beyond 12 months is necessary in patients with postoperative hypoparathyroidism, especially in those whose needs of treatment with Ca and calcitriol are reducing over time.

Can preoperative 25-hydroxyvitamin D levels predict transient hypocalcemia after total thyroidectomy?

Transient postoperative hypocalcemia is a common complication after total thyroidectomy. Evidence on contributing metabolic factors is contradictory. Our work aims to define the role of preoperative 25-hydroxyvitaminD levels in developing transient postoperative hypocalcemia. 183 consecutive patients who underwent total thyroidectomy at our institution (May 2017–December 2019) were included in the retrospective study. We reported gender, age, estimated glomerular filtration rate, creatinine, preoperative 25-hydroxyvitaminD, serum pre- and postoperative calcium, pre- and postoperative PTH levels and transient postoperative hypocalcemia occurrences. We compared variables both among patients with and without transient postoperative hypocalcemia and between patients with different 25-hydroxyvitaminD levels (< 10 ng/ml deficitary; 11–30 ng/ml insufficient; > 30 ng/ml, normal). A binomial logistic regression model evaluating the risk for transient postoperative hypocalcemia was elaborated. Patients with transient postoperative hypocalcemia had lower levels of postoperative PTH (p < 0.001) and more frequently normal or deficitary 25-hydroxyvitaminD levels (p = 0.05). When comparing patients according to their 25-hydroxyvitaminD levels, insufficiency was associated with a lower rate of transient postoperative hypocalcemia (p = 0.05); deficiency was associated with higher preoperative PTH (p = 0.021), postoperative PTH (p = 0.043) and estimated glomerular filtration rate (p = 0.031) and lower serum creatinine (p = 0.014). In the regression model higher preoperative PTH (OR = 1.011, p = 0.041) and 25-hydroxyvitaminD deficiency (OR = 0.343, p = 0.011) significantly predicted transient postoperative hypocalcemia. Data analysis revealed a correlation between transient postoperative hypocalcemia and 25-hydroxyvitaminD levels: our work points towards the possibility to stratify the risk of transient postoperative hypocalcemia according to patients’ preoperative 25-hydroxyvitaminD status.

Characteristics of patients with chronic hypoparathyroidism not adequately controlled with conventional treatment and management patterns in Spain

BACKGROUND AND OBJECTIVE

The current guidelines on hypoparathyroidism offer a model for treating patients but do not cover real-world situations or patient diversity. Given the lack of data regarding hypoparathyroidism, a Delphi panel was convened in Spain to establish consensus in defining the characteristics of patients with chronic hypoparathyroidism not adequately controlled with conventional treatment, as well as to investigate patterns of management.

MATERIAL AND METHODS

A presentation matrix provided a framework for characterizing inadequately controlled chronic hypoparathyroidism, based on four predefined patient groups: group 1 (normal biochemical levels and the patient feeling well); group 2 (abnormal biochemical levels and the patient feeling well); group 3 (normal biochemical levels and the patient feeling unwell); and group 4 (abnormal biochemical levels and the patient feeling unwell). Based on Likert scales (scored 1-9), the experts were asked to state their agreement/disagreement with the characteristics of patients with chronic hypoparathyroidism, including demographic data, family history, comorbidities, biochemical values, symptoms and quality of life. Consensus was achieved when ≥66% of the respondents were in agreement.

RESULTS

Consensus was achieved on the importance of assessing demographic data and comorbidities (e.g., renal complications) in groups 2, 3 and 4; family medical history in groups 2 and 3; biochemical parameters (e.g., calcemia/urinary calcium excretion) in groups 2 and 4; and clinical symptoms and quality of life in groups 3 and 4. Consensus was also reached regarding the maintenance of several biochemical parameters and the need for personalized treatment and training in symptoms and complications.

CONCLUSIONS

The Spanish expert panel reached consensus defining key disease parameters and factors of importance for characterizing and treating patients with inadequately controlled chronic hypoparathyroidism.

Role of the 2018 American Thyroid Association statement on postoperative hypoparathyroidism: a 5-year retrospective study

Background

Definitions of postoperative hypoparathyroidism (hypoPT) have never reached consent until the American Thyroid Association (ATA) statement was released, with new characteristics and challenges.

Methods

Patients with papillary thyroid carcinoma who underwent primary total thyroidectomy between January 2013 and June 2018 were retrospectively enrolled. Symptoms of hypocalcemia and their frequency were stringently followed. Patients were divided into groups according to the ATA statement. Incidence of postoperative hypoPT and serum parathyroid hormone levels accompanied by calcium levels, from 1-day to at least 24-month follow-up.

Results

A total of 1749 patients were included: 458 (26.2%) had transient and 63 (3.6%) had permanent hypoPT. Transient hypoPT was found in 363 (20.7%) patients with biochemical hypoPT, 72 (4.1%) with clinical hypoPT, and 23 (1.3%) with relative hypoPT; permanent hypoPT was detected in 8 (0.5%) patients with biochemical hypoPT, 55 (3.1%) with clinical hypoPT, and none with relative hypoPT. Female sex, age ≥ 55 years, unintentional parathyroid gland resection, and autotransplantation of ≥ 2 parathyroid glands were independent risk factors for transient biochemical hypoPT. Age ≥ 55 years, bilateral central neck dissection, and isthmus tumor location were independent risk factors for transient clinical hypoPT. A postoperative 1-day percentage of parathyroid hormone (PTH) reduction of > 51.1% was an independent risk factor for relative hypoPT (odds ratio, 4.892; 95% confidence interval, 1.653–14.480; P = 0.004). No independent risk factor for permanent hypoPT was found.

Conclusion

ATA diagnostic criteria for postoperative hypoPT are of great value in differentiating patients by hypocalcemia symptoms and choosing corresponding clinical assistance; however, they may underestimate the actual incidence.

Hypoparathyroidism after thyroidectomy: A 20-year experience at a children's hospital

INTRODUCTION

Hypoparathyroidism (HP) is the most common complication of total thyroidectomy and can be an emergency.

OBJECTIVES

To describe the prevalence of HP after total thyroidectomy in children under 14 years of age, the variables related to its appearance and its clinical expression.

PATIENTS AND METHODS

Retrospective study at a children's hospital in the last 20 years. HP was defined by the need to supplement calcium after the intervention and was considered permanent if it could not be suspended within 12 months. Fisher's statistical method of comparison of proportions.

RESULTS

Thirty-nine children and adolescents (26 females) with an age range of 3.67 to 14.00 years. In 25 patients, the intervention was prophylactic and in 14 it was therapeutic. Fourteen suffered accidental excision of some parathyroid gland, but none more than t2 of them. Twelve presented HP, of which 3 were permanent; 5 presented clinical symptoms; one of them was an emergency. The frequency of HP was 4/4 when 2 parathyroids were dissected, 2/10 when one was dissected, and 6/25 when none were dissected (P=.02). In the prophylactic interventions, it was 6/25 compared to 6/14 in the therapeutic ones (P=.29). The 3 cases of permanent HP were in children under 6 years of age, and it did not occur in any older children (P=.09).

CONCLUSIONS

HP is a common and sometimes serious complication in children after total thyroidectomy. It can occur, and even be permanent, even if the intervention is prophylactic and parathyroid glands remain in situ. Younger age could be a risk factor.

Prophylactic Central Neck Dissection in Well-differentiated Thyroid Cancer

Well-differentiated cancers, both papillary and follicular, account for 90% of all diagnosed thyroid cancers. They have an indolent disease course with a 20-year disease-specific survival over 90%. According to current guidelines, the therapy of choice for well-differentiated thyroid carcinoma is total thyroidectomy or lobectomy. The indication for prophylactic central neck dissection is still a controversial issue and the subject of unfinished and ongoing debate. There is no indication for prophylactic central neck dissection in follicular thyroid carcinomas, which primarily metastasize hematogenously. In small solitary papillary thyroid carcinomas (T1 and T2), prophylactic central neck dissection is not indicated as it does not bring benefits in terms of improved patient survival and at the same time significantly increases the risk of temporary and permanent postoperative complications. Prophylactic central neck dissection is indicated in advanced papillary thyroid cancers (T3 and T4) and all other high-risk well-differentiated thyroid cancer, as well as in the presence of metastatic lymph nodes in the lateral neck.

What are the real rates of temporary hypoparathyroidism following thyroidectomy? It is a matter of definition: a systematic review

INTRODUCTION

Post-operative hypoparathyroidism is the most encountered complication of thyroid surgery and is classified as temporary or permanent. However, its incidence varies greatly in the literature ranging from 0.5% to 65%. This can be mainly attributed to the different definition of hypoparathyroidism used in each study and especially to the different time cutoff applied to distinguish temporary from permanent hypoparathyroidism.

METHODS

We conducted a systematic literature search in PubMed, Scopus, Cochrane and GoogleScholar databases, as well as grey literature. Ultimately, 45 articles with 23,164 patients in total were included in this review. These articles used either the cutoff of six or twelve post-operative months to distinguish temporary from permanent hypoparathyroidism.

RESULTS

The overall incidence of permanent hypoparathyroidism diagnosed at 6 months post-operatively was 4.11% and 4.08% at 12 months post-operatively. There was no statistically significant difference between the two groups (p = 0.92).

CONCLUSIONS

We suggest that adhering to the current guidelines that recommend diagnosing temporary hypoparathyroidism when recovery is made within 6 months after surgery is important when conducting future research in order to narrow the gap that exists currently in the literature, as well as when deciding to put patients on long-term calcium supplements.

Selective Parathyroid Autotransplantation During Total Thyroidectomy for Papillary Thyroid Carcinoma: A Cohort Study

Purpose: The relationship between the selective parathyroid gland (PG) autotransplantation and hypoparathyroidism is still not completely clear. The aim was to ascertain whether the number of autotransplanted PGs affected the incidence of hypoparathyroidism and recovery of parathyroid function in the long-term for patients with papillary thyroid carcinoma (PTC). Methods: A retrospective cohort study included all patients with PTC who had underwent primary total thyroidectomy with central neck dissection between January 2013 and December 2017. The patients were divided into three groups (0, 1, and 2 PGs autotransplanted, respectively). Results: Of the 2,477 patients, 634 (25.6%) received no PG autotransplantation, 1,078 (43.5%) and 765 (30.9%) were autotransplanted 1 and 2 PGs, respectively, and the incidence of permanent hypoparathyroidism (>1 year) was 1.7%, 0.7%, and 0.4% (P = 0.0228). Both 1 or 2 PGs autotransplanted increased the incidence of transient biochemical hypoparathyroidism (odds ratio [OR], 1.567; 95% confidence interval [CI], 1.258-1.953; P < 0.0001; OR, 2.983; 95% CI, 2.336-3.810; P < 0.0001, respectively) but reduced the incidence of permanent hypoparathyroidism (OR, 0.373; 95% CI, 0.145-0.958; P = 0.0404; OR, 0.144; 95% CI, 0.037-0.560; P = 0.0052, respectively). Both 1 or 2 PGs autotransplanted did not independently influence the occurrence of hypocalcemia symptoms. Conclusion: Selective parathyroid autotransplantation is less likely to lead to post-operative symptomatic hypocalcemia, although it could lead to a transient decrease in parathyroid hormone. However, in the long run, it is still an effective strategy to preserve parathyroid function.

Risk factors for postoperative morbidity after thyroid surgery in a PROSPECTIVE cohort of 1500 patients

BACKGROUND

Postoperative hypocalcaemia, recurrent laryngeal nerve palsy and postoperative bleeding are the most frequent postoperative complications after thyroid surgery, and therefore often used as quality indicators of thyroid surgery. We aimed to assess postoperative morbidity in a high-volume endocrine surgery unit, and to detect which factors are associated with higher risks.

METHODS

Prospective surgical cohort in a high-volume tertiary referral centre for endocrine surgery in xxx. The first 1500 patients operated with hemi or total thyroidectomy during 2010-2019 were included. Postoperative hypocalcaemia, recurrent laryngeal nerve palsy and postoperative bleeding were assessed in relation to pre- and peri-operative characteristics using multivariable logistic regression analyses, expressed as odds ratios and 95% confidence intervals.

RESULTS

Overall, 1043 patients (69.5%) received a total thyroidectomy and 457 (30.5%) a hemithyroidectomy. Permanent hypocalcaemia occurred in 3.1%, permanent recurrent laryngeal nerve palsy in 1.8% and surgical reintervention for bleeding in 2.6%. Younger age, female sex and cancer were risk factors for permanent hypocalcaemia. No clear risk factors could be identified for permanent nerve palsy. Female sex, high body mass index and heavier thyroids were protective against postoperative bleeding after total thyroidectomy.

CONCLUSIONS

Surgical experience in endocrine surgery seems beneficial for clinical outcomes and contributes to organizational efficiency. A low complication risk can be obtained by trained high-volume endocrine surgeons, yet the risk is not negligible.

The Optimal Parathyroid Hormone Cut-Off Threshold for Early and Safe Management of Hypocalcemia After Total Thyroidectomy

OBJECTIVE

To define optimal intact parathyroid hormone (iPTH) cut-off threshold predictive of hypocalcemia after total thyroidectomy for safe and effective postoperative management.

METHODS

This prospective single center study was done in 2 phases. In phase I, predictors of symptomatic hypocalcemia were analyzed and the receiver operating characteristic curve was used to define the optimal iPTH cut-off threshold predictive of hypocalcemia. Phase II studied giving prompt prophylactic supplemental calcium and vitamin D to all patients who had iPTH levels below the calculated threshold, while phase I patients were given prompt selective supplementation if they had postoperative hypocalcemia or symptoms.

RESULTS

Univariate analysis of patients in phase I showed that postoperative iPTH was the only significant variable that can predict symptomatic hypocalcemia. Using receiver operating characteristic curve and Youden index, the confirmed optimal cut-off threshold predictive of hypocalcemia was iPTH 19.95 pg/mL, with area under the curve of 0.903, 100% sensitivity, negative predictive value, and highest Youden index, while iPTH 15 pg/mL and iPTH 10 pg/mL were less optimal. Symptomatic hypocalcemia occurred in 30% of the phase I cohort who received selective supplementation versus 3% of those in the phase II cohort who received prophylactic supplementation. Return to emergency department and need for intravenous calcium were also significantly better in phase II.

CONCLUSION

iPTH cut-off for post-thyroidectomy hypocalcemia was 19.95 pg/mL. Low-risk patients were discharged with no supplementation while all high-risk patients received prompt calcium and vitamin D supplementation, which led to effective hypocalcemia management and safe 24-hour discharge.

Thyroid cancer patients satisfaction at the management outcome: an analysis of the results of a nationwide survey in 485 subjects

BACKGROUND

We aimed to measure satisfaction of patients with thyroid cancer concerning different aspects of healthcare.

METHODS

We developed a web-based survey. Questions focused on patient satisfaction with specialists, the health centers and departments, and the information received about their disease. Level of satisfaction was quantified using a scale of 1 to 5. Values ≥4 were considered a high degree of satisfaction.

RESULTS

Four hundred eighty-five patients (aged 43.4 ± 9.9 yrs., 88% females) completed the survey. A high overall satisfaction with the specialists was reported by 52.5% of patients. The most highly valued specialists were surgeons, oncologists, and endocrinologists. 56.5% of respondents reported a high overall satisfaction with the health centers and departments. Lastly, the proportion of patients who were highly satisfied with the information received was only 42.5%. The presence of complications was indirectly related with satisfaction with specialists and information. Satisfaction with health centers and services was directly related with the level of education and inversely related to the time of evolution of the disease.

CONCLUSION

Our results show a high degree of overall satisfaction of thyroid cancer patients. However, satisfaction can be improved in some areas, such with regards to the information provided to patients.

Characteristics of patients with chronic hypoparathyroidism not adequately controlled with conventional treatment and management patterns in Spain

BACKGROUND AND OBJECTIVE

The current guidelines on hypoparathyroidism offer a model for treating patients but do not cover real-world situations or patient diversity. Given the lack of data regarding hypoparathyroidism, a Delphi panel was convened in Spain to establish consensus in defining the characteristics of patients with chronic hypoparathyroidism not adequately controlled with conventional treatment, as well as to investigate patterns of management.

MATERIAL AND METHODS

A presentation matrix provided a framework for characterizing inadequately controlled chronic hypoparathyroidism, based on 4 predefined patient groups: group 1 (normal biochemical levels and the patient feeling well); group 2 (abnormal biochemical levels and the patient feeling well); group 3 (normal biochemical levels and the patient feeling unwell); and group 4 (abnormal biochemical levels and the patient feeling unwell). Based on Likert scales (scored 1-9), the experts were asked to state their agreement / disagreement with the characteristics of patients with chronic hypoparathyroidism, including demographic data, family history, comorbidities, biochemical values, symptoms and quality of life. Consensus was achieved when ≥ 66% of the respondents were in agreement.

RESULTS

Consensus was achieved on the importance of assessing demographic data and comorbidities (e.g., renal complications) in groups 2, 3 and 4; family medical history in groups 2 and 3; biochemical parameters (e.g., calcemia / urinary calcium excretion) in groups 2 and 4; and clinical symptoms and quality of life in groups 3 and 4. Consensus was also reached regarding the maintenance of several biochemical parameters and the need for personalized treatment and training in symptoms and complications.

CONCLUSIONS

The Spanish expert panel reached consensus defining key disease parameters and factors of importance for characterizing and treating patients with inadequately controlled chronic hypoparathyroidism.

Etiology and Diagnosis of Permanent Hypoparathyroidism after Total Thyroidectomy

Postoperative parathyroid failure is the commonest adverse effect of total thyroidectomy, which is a widely used surgical procedure to treat both benign and malignant thyroid disorders. The present review focuses on the scientific gap and lack of data regarding the time period elapsed between the immediate postoperative period, when hypocalcemia is usually detected by the surgeon, and permanent hypoparathyroidism often seen by an endocrinologist months or years later. Parathyroid failure after thyroidectomy results from a combination of trauma, devascularization, inadvertent resection, and/or autotransplantation, all resulting in an early drop of iPTH (intact parathyroid hormone) requiring replacement therapy with calcium and calcitriol. There is very little or no role for other factors such as vitamin D deficiency, calcitonin, or magnesium. Recovery of the parathyroid function is a dynamic process evolving over months and cannot be predicted on the basis of early serum calcium and iPTH measurements; it depends on the number of parathyroid glands remaining in situ (PGRIS)—not autotransplanted nor inadvertently excised—and on early administration of full-dose replacement therapy to avoid hypocalcemia during the first days/weeks after thyroidectomy.

Recovery of severely damaged parathyroid function after total thyroidectomy for thyroid cancer

Background

An extremely low parathyroid hormone (PTH) concentration after thyroidectomy may reflect the immediate severely damaged parathyroid function. The current study aimed to examine time-related changes of severely damaged parathyroid function on postoperative day 1 (SDPF-D1), which was here defined as serum PTH ≤1 pg/mL, and the risk factors of SDPF-D1.

Methods

This is a retrospective review of patients with thyroid cancer undergoing total thyroidectomy with or without central neck dissection (CND). The number of parathyroids preserved in situ, autotransplanted, or found in the final pathology was recorded and the corresponding parathyroid glands remaining in situ (PGRIS) score (PGRIS = 4 - parathyroids autotransplanted-parathyroids found in the final pathology) was calculated. Chronological changes of serum levels of PTH and total calcium were investigated for at least one year after surgery.

Results

One hundred and twenty-two of 344 patients included for analysis suffered from SDPF-D1. Patients with SDPF-D1 had a prolonged recovery in comparison with hypoparathyroidism patients without SDPF-D1, who fully recovered within 6 months after thyroidectomy. The PGRIS score in patients with permanent hypoparathyroidism was significantly lower than other patients with SDPF-D1who fully recovered.

Conclusions

Most patients with SDPF-D1 could fully recover within one year after total thyroidectomy. Less parathyroids removed and autotransplanted contributed to a quick recovery of SDPF-D1.

Feasibility of Autofluorescence for Parathyroid Glands During Thyroid Surgery and the Risk of Hypocalcemia: First Results in Belgium and Review of the Literature

Background. Post-operative hypocalcemia remains the most frequent complication after total thyroidectomy. Recently, autofluorescence imaging was introduced to detect parathyroid glands early during dissection. Aim. We aimed to check the feasibility of autofluorescence regarding the number of parathyroid glands visualised and the risk of post-operative hypocalcemia. Methods. In a prospectively gathered cohort of patients undergoing thyroid surgery, we describe the risk of hypocalcemia in relation to the number of parathyroid glands visualised during surgery (and the risk reported in the scientific literature) and the feasibility to obtain an autofluorescence of the parathyroid glands. Results. From 2010 to 2019, 1083 patients were referred for total thyroidectomy in our tertiary referral centre for endocrine surgery, of which, 40 consecutive cases were operated using autofluorescence. Among the autofluorescence group, 14 (35.0%) had all 4 parathyroid glands visualised, compared to 147 (14.1%) in the other patients, without differences in the number of parathyroid glands reimplanted. No permanent hypocalcemia occurred in the autofluorescence group and 17.5% temporary hypoparathyroidism, compared to 3.1% and 31.9% among the other patients, and 4% (95% confidence interval [CI] 3-5%) and 19% (95% CI 15-24%) in the literature. Conclusion. Autofluorescence imaging provides reliable real-time visualisation at any point during thyroid surgery and helps to identify the parathyroid glands before detection with the naked eye. To date, it cannot be used as a standard technique and does not replace meticulous dissection. To become a useful adjunct in peroperative parathyroid management, large multicentre studies need to establish a potential clinical benefit of this novel technique.

Permanent postoperative hypoparathyroidism: an analysis of prevalence and predictive factors for adequacy of control in a cohort of 260 patients

Background

Recent guidelines for the treatment of hypoparathyroidism emphasize the need for long-term disease control, avoiding symptoms and hypocalcaemia. Our aim has been to analyze the prevalence of poor disease control in a national cohort of patients with hypoparathyroidism, as well as to evaluate predictive variables of inadequate disease control.

Methods

From a nation-wide observational study including a cohort of 1792 patients undergoing total thyroidectomy, we selected 260 subjects [207 women and 53 men, aged (mean ± SD) 47.2±14.8 years] diagnosed with permanent hypoparathyroidism. In every patient demographic data and details on surgical procedure, histopathology, calcium (Ca) metabolism, and therapy with Ca and calcitriol were retrospectively collected. A patient was considered not adequately controlled (NAC) if presented symptoms of hypocalcemia or biochemical data showing low serum Ca levels or high urinary Ca excretion.

Results

Two hundred and twenty-one (85.0%) patients were adequately controlled (AC) and 39 (15.0%) were NAC. Comparison between AC and NAC patients did not show any significant difference in demographic, surgical, and pathological features. Rate of hospitalization during follow-up was significantly higher among NAC patients in comparison with AC patients (35.9% vs. 10.9%, P<0.001). Dose of oral Ca and calcitriol were also significantly higher in NAC subjects. In a subgroup of 129 patients with serum parathyroid hormone (PTH) levels available, we found that NAC patients exhibited significantly lower postoperative PTH concentrations than AC patients [median (interquartile range) 3 (1.9-7.8) vs. 6.9 (3.0-11) pg/mL; P=0.009].

Conclusions

In a nation-wide cohort of 260 subjects with definitive hypoparathyroidism, 15% of them had poor disease control. These patients required higher doses of oral Ca and calcitriol, had higher rate of hospitalization during follow-up and showed lower PTH concentrations in the postoperative period.

Development and validation of a new model for predicting hypocalcaemia after total thyroidectomy: the NuGra model

BACKGROUND

Hypocalcaemia is the most frequent complication after total thyroidectomy. Finding a method for its early detection has become a priority. A single-center prospective cohort study was conducted to identify risk factors for postoperative hypocalcaemia, develop an early detection model, and test its validity in a different group of patients.

METHODS

The sample was composed of patients who underwent a total thyroidectomy between May 2012 and September 2015. Demographic, clinical, laboratory, and surgical data were collected. The incidence of hypocalcaemia and permanent hypoparathyroidism was calculated. Bivariate and multivariate analysis identified several independent predictors of hypocalcaemia, which were used to design a predictive model. The validity of the model was subsequently tested in a different cohort. Area under the ROC curve (AUROC) was calculated to determine its predictive power.

RESULTS

The study and validation groups included 352 and 118 patients, respectively. Seventy-three patients developed laboratory-confirmed hypocalcaemia (20.7%), and symptomatic in 43 (12.2%). Multivariate analysis confirmed as independent predictors of hypocalcaemia the higher number of parathyroid glands identified [OR 1.41(0.98, 2.02); p = 0.063] and pre-to-postoperative gradient of parathormone decline [OR 1.06(1.04, 1.08); p < 0.001]. Based on these variables, the NuGra (Number of parathyroid glands identified-Gradient of decline) model was developed for predicting laboratory-confirmed hypocalcaemia. Its predictive power was high (AUROC 0.902, CI 0.857-0.947) for the study and the validation group (AUROC 0.956, CI 0.919-0.993).

CONCLUSIONS

A higher number of parathyroid glands identified and a higher gradient of parathormone decline are risk factors for post-thyroidectomy hypocalcaemia. The NuGra model is useful for early prediction of individual risk for hypocalcaemia.

Diagnosis and management of hypocalcemia

The aim of this clinical narrative review is to summarize and critically appraise the literature on the differential diagnosis of hypocalcemia and to provide its correct management. Calcium is essential for muscle contraction and neurotransmitter release, but clinical manifestations of hypocalcaemia (serum calcium level <8 mg/dl; 2.12 mmol/L) may involve almost any organ and system and may range from asymptomatic to life-threating conditions. Disorders causing hypocalcemia can be divided into parathyroid hormone (PTH) and non-PTH mediated. The most frequent cause of hypocalcemia is postsurgical hypoparathyroidism, while a more comprehensive search for other causes is needed for appropriate treatment in the non PTH-mediated forms. Intravenous calcium infusion is essential to raise calcium levels and resolve or minimize symptoms in the setting of acute hypocalcemia. Oral calcium and/or vitamin D supplementation is the most frequently used as treatment of chronic hypocalcemia. In hypoparathyroidism, providing the missing hormone with the use of the recombinant human (rh) PTH(1-84) has been recently approved both by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). This new therapy has the advantage of being effective for correcting serum calcium levels and significantly reducing the daily requirements of calcium and active vitamin D supplements. However, due to the high cost, a strict selection of candidates to this therapy is necessary. More challenging is the long-term hypocalcemia treatment, due to its associated complications. The development of long-acting recombinant human PTH will probably modify the management of chronic hypoparathyroidism in the future.

[Reliability of DRG Routine Data to Analyse Treatment Outcome and Complications of Thyroid Surgery. A Critical Analysis of Data of Patient Records Compared to Administrative Data]

INTRODUCTION

Quality assurance of the thyroid surgery has been an important part of the work of the endocrine surgeon. For most analyses, data from register files or studies have been used. Administrative data taken from routine data are increasingly used in quality assurance for evaluation. The aim of the study is to determine the reliability of routine data to analyse the treatment outcome and complications of thyroid surgery.

PATIENTS AND METHODS

In a cross-sectional study, we compared records of 121 patients with thyroid surgery for one year with the data of quality assurance of clinical routine. We determined sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of complications.

RESULTS

Screening of administrative data identified 40 specific complications; 84 by patient records. Sensitivities for the detection of complications using administrative data ranged from 31.3 to 60.0%. Specificities ranged from 97.0 to 100%; PPV were 0.77 - 1.0 and NPV were 0.56 - 1.0.

CONCLUSION

Quality assurance of clinical routine data of the thyroid surgery shows deficiencies in sensitivity accompanied by high specificity. It is necessary to increase the validity of administrative routine data to carry out a reliable clinic quality analysis or to prepare volume-outcome relationships in clinical health service research. The parameter of hypocalcaemia shows the most limitations due to quality assurance of clinical routine data.