Influence of gender and women's age on the prevalence of parathyroid failure after total thyroidectomy for multinodular goiter

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.

Recurrent multinodular goitre and primary hyperparathyroidism due to adenoma arising in a parathyroid autotransplant more than 20 years after near-total thyroidectomy

The patient is a female in her 60s with a remote history of a near-total thyroidectomy in 1997 for multinodular goitre. At the initial operation, she sustained a left recurrent laryngeal nerve injury. A devascularised parathyroid gland was autotransplanted into the right sternocleidomastoid muscle. She had been off of thyroid hormone for long periods, and her most recent levothyroxine requirement had fallen to only 25 mcg daily. The patient presented more than 20 years after her thyroidectomy with hoarseness, fatigue and dyspnoea. Laboratory studies suggested primary hyperparathyroidism. Imaging demonstrated bilateral pulmonary emboli and bulky thyroid tissue extending into her mediastinum. She underwent a completion thyroidectomy with the removal of a parathyroid adenoma arising in the autotransplanted parathyroid. This case illustrates the possibility of regrowth of benign thyroid tissue after thyroidectomy. In addition, to our knowledge, this is the first case report of a parathyroid adenoma arising from autotransplantation of a normal parathyroid.

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).

Diabetes mellitus postoperatif hipoparatiroidizm için bir risk faktörü olabilir mi?

Aim: Postoperative hypoparathyroidism (postop hypoPT) is usually seen after aggressive neck surgery, and can be fatal if left untreated. To the best our knowledge there is no study in literature that directly investigates the association between diabetes mellitus (DM) and postop hypoPT. In this study, we aimed to determine whether DM increases the risk of permanent postop hypoPT. Materials and Methods: Patients presenting to endocrinology outpatient clinic with a diagnosis of permanent postoperative hypoparathyroidism, were studied retrospectively. Patients older than 18 years of age were included in the study if one year had passed after the neck operation. Results: The average age of 131 patients who met the inclusion criteria was 49 ± 12. 93.9% of the patients were women and the patients were generally obese or overweight (mean body mass index= 30±5.29 kg/m2). While 14.5% of the patients were diabetic and 32.8% prediabetic (47.3% had impaired carbohydrate tolerance), 52.7% had normal glucose metabolism. Conclusion: The rate of DM / prediabetes (preDM) in patients diagnosed with postop hypoPT and the prevalence of DM / preDM in Turkish population were similar. Even though DM is associated with endothelial dysfunction, our findings suggest that DM is not a risk factor for postop hypoPT.

A territory-wide assessment of the incidence of persistent hypoparathyroidism after elective thyroid surgery and its impact on new fracture risk over time

BACKGROUND

Although persistent (≥6 months) postoperative hypoparathyroidism is often believed to be rare after elective total thyroidectomy, we hypothesized a higher incidence in the community and that patients with persistent postoperative hypoparathyroidism may have a higher fracture risk. A population-based analysis was performed using an electronic health database to address these issues.

METHODS

All elective total thyroidectomies performed in 14 major hospitals across the territory over 20 years were analyzed. Persistent postoperative hypoparathyroidism was defined by the requirement of oral calcium and vitamin D shortly postoperatively and continued for ≥6 months. Those with albumin-corrected calcium <1.90 mmol/L on ≥1 occasion beyond 1 year postoperation were considered suboptimally controlled. Patients were followed until an index fracture, death, or the time of analysis, whichever was earlier. Multivariable Cox regression analysis was used to identify clinical predictors for fractures.

RESULTS

Among 4,123 eligible patients, 460 patients (11.2%) had persistent postoperative hypoparathyroidism. Over a median of 10.3 years, 126 patients suffered from a new fracture (2.77 per 1,000 person-years). There was no difference in fracture events between patients with and without persistent postoperative hypoparathyroidism (P = .761). Subgroup analyses according to the adequacy of persistent postoperative hypoparathyroidism control did not reveal significant differences in fracture events. Age, female, history of fall, and diabetes independently predicted post-thyroidectomy fractures.

CONCLUSION

Persistent postoperative hypoparathyroidism appeared to be a more common complication in the community after elective total thyroidectomy than previously thought. We did not observe a significant difference in fracture risk between patients with and without persistent postoperative hypoparathyroidism. The impact of persistent postoperative hypoparathyroidism control on fracture risk remained to be determined.

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.

Prevalence of basal ganglia and carotid artery calcifications in patients with permanent hypoparathyroidism after total thyroidectomy

OBJECTIVE

Permanent hypoparathyroidism is an uncommon disease resulting most frequently from neck surgery. It has been associated with visceral calcifications but few studies have specifically this in patients with post-surgical hypoparathyroidism. The aim of the present study was to assess the prevalence of basal ganglia and carotid artery calcifications in patients with long-term post-thyroidectomy hypoparathyroidism compared with a control population.

DESIGN

Case-control study.

METHODS

A cross-sectional review comparing 29 consecutive patients with permanent postoperative hypoparathyroidism followed-up in a tertiary reference unit for Endocrine Surgery with a contemporary control group of 501 patients who had an emergency brain CT scan. Clinical variables and prevalence of basal ganglia and carotid artery calcifications were recorded.

RESULTS

From a cohort of 46 patients diagnosed with permanent hypoparathyroidism, 29 were included in the study. The mean duration of disease was 9.2 ± 7 years. Age, diabetes, hypertension, smoking and dyslipidemia were similarly distributed in case and control groups. The prevalence of carotid artery and basal ganglia calcifications was 4 and 20 times more frequent in patients with permanent hypoparathyroidism, respectively. After propensity score matching of the 28 the female patients, 68 controls were matched for age and presence of cardiovascular factors. Cases showed a four-fold prevalence of basal ganglia calcifications, whereas that of carotid calcifications was similar between cases and controls.

CONCLUSION

A high prevalence of basal ganglia calcifications was observed in patients with post-surgical permanent hypoparathyroidism. It remains unclear whether carotid artery calcification may also be increased.