A Population-Based Study of the Epidemiology of Chronic Hypoparathyroidism

Quality of life in patients with hypoparathyroidism receiving standard treatment: an updated systematic review

PURPOSE

Hypoparathyroidism is defined by hypocalcemia with inappropriately normal or low parathyroid hormone levels. The current standard treatment consists of lifelong calcium and/ or vitamin D supplementation. Even while on stable treatment regimens, hypoparathyroid patients might still suffer from symptoms that can negatively impact their quality of life.

METHODS

A systematic literature review to identify the current knowledge regarding quality of life in patients with hypoparathyroidism receiving standard treatment was performed on November 1st, 2023. PubMed as well as Web of Science were searched. The systematic review is registered in PROSPERO (#CRD42023470924).

RESULTS

After removal of duplicates, 398 studies remained for title and abstract screening, after which 30 were included for full-text screening. After exclusion of seven studies with five studies lacking a control population, one using a non-validated questionnaire, and one being a subsample of the larger included study, 23 studies were included in this systematic review. The majority of the included studies used a guideline-conform definition of hypoparathyroidism, and the SF-36 was the most often applied tool. Almost all studies (87%) reported statistically significantly lower scores in at least one quality of life domain compared to a norm population or controls.

CONCLUSION

Patients with hypoparathyroidism receiving standard treatment report impairments in quality of life. The reasons for these impairments are probably multifaceted, making regular monitoring and the inclusion of various professionals necessary.

Coronary calcium score in patients with post-surgical hypoparathyroidism

Objective

This study aimed to evaluate the cardiovascular risk of patients with post-surgical hypoparathyroidism through coronary calcium score (CACS) evaluation andcardiovascular risk calculators.

Subjects and methods

Patients with post-surgical hypoparathyroidism (HG = 29) were compared to a control group (CG = 29), matched by sex and age. Demographic and clinical data were captured by a questionnaire or patient files. Both groups performed a thoracic-computed tomography to evaluate the CACS and the cardiovascular risk was calculated by two risk calculators.

Results

In the HG, the supplementation of calcium varied between 500 to 2,000 mg/day and the mean calcitriol was 0.5 ± 0.29 mcg/day. The mean serum calcium and phosphorus were 8.32 ± 0.68 and 4.92 ± 0.87 mg/dL, respectively, and in the range recommended for hypoparathyroidism. The Brazilian Society of Cardiology's risk calculator showed a difference among groups, with no patient in the HG with low risk, but the CACS was similar. A positive CACS in the HG was associated with obesity and high BMI but not with calcium and/or vitamin D supplementation.

Conclusion

In conclusion, patients with hypoparathyroidism did not show increased CACS, and it was not related to supplementation.

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.

Pregnancy, delivery and neonatal outcomes among women with hypoparathyroidism-A population-based study

OBJECTIVE

Data are inconclusive regarding pregnancy complications associated with maternal chronic hypoparathyroidism. Therefore, we aimed to compare pregnancy, delivery and neonatal outcomes in patients affected by chronic hypoparathyroidism to those without chronic hypoparathyroidism.

DESIGN

A retrospective population-based study utilising data from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (HCUP-NIS) database over 11 years from 2004 to 2014 inclusively. Multivariate logistic regression was used to control for confounders.

PATIENTS

Patients with chronic hypoparathyroidism compared with those without.

MEASUREMENTS

Obstetric and neonatal outcomes.

RESULTS

We identified 204 pregnancies in mothers with chronic hypoparathyroidism and 9,096,584 pregnancies without chronic hypoparathyroidism. After adjusting for age, insurance plan type, obesity, chronic hypertension, thyroid disease, pregestational diabetes mellitus, and previous caesarean section, patients in the hypoparathyroidism group, compared with those without hypoparathyroidism, were found to have an increased rate of preterm birth (<37 weeks) (19.1% vs. 7.2%, aOR: 2.49, 95% confidence interval [CI]: 1.74-3.54, p < 0.0001, respectively); and blood transfusions (4.9% vs. 1.0%, aOR: 4.07, 95% CI: 2.15-7.73, p < -0.0001). Neonates to mothers with chronic hypoparathyroidism had a higher rate of congenital anomalies (4.4% vs. 0.4%, aOR: 6.50, 95% CI: 3.31-12.75, p < 0.0001), with comparable rates of small-for-gestational-age neonates and intrauterine foetal death.

CONCLUSION

This is the largest study of chronic hypoparathyroidism in pregnancy to date. We found significant increases in the rates of preterm birth, blood transfusions and congenital anomalies in chronic hypoparathyroidism. Our findings highlight the importance of identifying chronic hypoparathyroidism as a risk factor for pregnancy and neonatal complications, although it remains unknown if maintaining calcium in the target range will mitigate these risks.

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).

Evaluation and Management of Hypoparathyroidism Summary Statement and Guidelines from the Second International Workshop

This clinical practice guideline addresses the prevention, diagnosis, and management of hypoparathyroidism (HypoPT) and provides evidence-based recommendations. The HypoPT task forces included four teams with a total of 50 international experts including representatives from the sponsoring societies. A methodologist (GG) and his team supported the taskforces and conducted the systematic reviews. A formal process following the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology and the systematic reviews provided the structure for seven of the guideline recommendations. The task force used a less structured approach based on narrative reviews for 20 non-GRADEd recommendations. Clinicians may consider postsurgical HypoPT permanent if it persists for >12 months after surgery. To predict which patients will not develop permanent postsurgical HypoPT, we recommend evaluating serum PTH within 12 to 24 hours post total thyroidectomy (strong recommendation, moderate quality evidence). PTH > 10 pg/mL (1.05 pmol/L) virtually excludes long-term HypoPT. In individuals with nonsurgical HypoPT, genetic testing may be helpful in the presence of a positive family history of nonsurgical HypoPT, in the presence of syndromic features, or in individuals younger than 40 years. HypoPT can be associated with complications, including nephrocalcinosis, nephrolithiasis, renal insufficiency, cataracts, seizures, cardiac arrhythmias, ischemic heart disease, depression, and an increased risk of infection. Minimizing complications of HypoPT requires careful evaluation and close monitoring of laboratory indices. In patients with chronic HypoPT, the panel suggests conventional therapy with calcium and active vitamin D metabolites as first-line therapy (weak recommendation, low-quality evidence). When conventional therapy is deemed unsatisfactory, the panel considers the use of PTH. © 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).

UK national chronic hypoparathyroidism audit

OBJECTIVES

Individuals with chronic hypoparathyroidism may experience suboptimal medical care with high frequency of unplanned hospitalisation and iatrogenic harm. In 2015 the European Society for Endocrinology published consensus guidelines on the management of chronic hypoparathyroidism. We set out to audit compliance with these guidelines.

METHODS

Using these recommendations as audit standards we worked with the Society for Endocrinology and Parathyroid UK to conduct a national audit of management of chronic hypoparathyroidism in the United Kingdom. Endocrine leads in 117 endocrine departments were invited to participate in the survey by completing a data collection tool on up to 5 sequential cases of chronic hypoparathyroidism seen in their outpatient clinics in the preceding 12 months. Data were collected on 4 treatment standards and 9 monitoring standards. Data on hospitalisations and Quality of Life monitoring were also collected.

RESULTS

Responses were received from 22 departments giving a response rate of 19%, concerning 80 individual cases. The mean age of subjects was 48.4 years. The main findings were that the commonest cause of hypoparathyroidism was post surgical (66.3%). Treatments taken by the group included activated vitamin D analogues (96.3%), oral calcium salts (66.3%), vitamin D supplements (17.5%), thiazide diuretics (5%) and rhPTH_1-34 (1.3%). Compliance with the audit standards varied between 98.8% and 60% for the treatment standards and between 91.3% and 20% for the monitoring standards. Some of the areas of weakness revealed include low rates of 24 h urinary calcium excretion monitoring, serum magnesium monitoring and low rates of renal imaging where indicated. In addition and importantly, 16.3% of subjects had experienced at least one hospital admission in the preceding 12 months.

CONCLUSION

We conclude that further improvements in the UK national standard of management of chronic hypoparathyroidism should be made and that this will benefit both quality of life, morbidity and potentially mortality in this group of patients.

Unrecognized Primary Hypoparathyroidism with Severe Hypocalcemia in the Presence of COVID-19 Infection

Primary hypoparathyroidism (PHPT) is a rare disease most commonly caused by surgical parathyroid glands destruction or genetic disorders. PHPT manifestation varies from subclinical to acute or even lethal symptoms. In atypical presentation the signs of hypocalcemia could be missed, and asymptotic chronic hypocalcemia could manifest only in the presence of exacerbated comorbidities, infections, hypomagnesemia or certain medications. We present a case of PHPT with severe hypocalcemia manifesting as seizures and delirium in a presence of COVID-19 infection.

Identifying Clinical Characteristics of Hypoparathyroidism in Turkey: HIPOPARATURK-NET Study

Hypoparathyroidism is an orphan disease with ill-defined epidemiology that is subject to geographic variability. We conducted this study to assess the demographics, etiologic distribution, treatment patterns and complication frequency of patients with chronic hypoparathyroidism in Turkey. This is a retrospective, cross-sectional database study, with collaboration of 30 endocrinology centers located in 20 cities across seven geographical regions of Turkey. A total of 830 adults (mean age 49.6 ± 13.5 years; female 81.2%) with hypoparathyroidism (mean duration 9.7 ± 9.0 years) were included in the final analysis. Hypoparathyroidism was predominantly surgery-induced (n = 686, 82.6%). The insulting surgeries was carried out mostly due to benign causes in postsurgical group (SG) (n = 504, 73.5%) while patients in nonsurgical group (NSG) was most frequently classified as idiopathic (n = 103, 71.5%). The treatment was highly dependent on calcium salts (n = 771, 92.9%), calcitriol (n = 786, 94.7%) and to a lower extent cholecalciferol use (n = 635, 76.5%) while the rate of parathyroid hormone (n = 2, 0.2%) use was low. Serum calcium levels were most frequently kept in the normal range (sCa 8.5-10.5 mg/dL, n = 383, 46.1%) which might be higher than desired for this patient group. NSG had a lower mean plasma PTH concentration (6.42 ± 5.53 vs. 9.09 ± 7.08 ng/l, p < 0.0001), higher daily intake of elementary calcium (2038 ± 1214 vs. 1846 ± 1355 mg/day, p = 0.0193) and calcitriol (0.78 ± 0.39 vs. 0.69 ± 0.38 mcg/day, p = 0.0057), a higher rate of chronic renal disease (9.7% vs. 3.6%, p = 0.0017), epilepsy (6.3% vs. 1.6%, p = 0.0009), intracranial calcifications (11.8% vs. 7.3%, p < 0.0001) and cataracts (22.2% vs. 13.7%, p = 0.0096) compared to SG. In conclusion, postsurgical hypoparathyroidism is the dominant etiology of hypoparathyroidism in Turkey while the nonsurgical patients have a higher disease burden with greater need for medications and increased risk of complications than the postsurgical patients.

Effect of postsurgical chronic hypoparathyroidism on morbidity and mortality: a systematic review and meta-analysis

Background

Hypoparathyroidism (HypoPT) is a common sequela of anterior neck surgeries. While the acute risks of HypoPT are well known, emerging evidence is beginning to define the risks chronic HypoPT poses to patients. This meta-analysis aims to evaluate that risk and give more insight into its consequences.

Methods

A systematic review and meta-analysis were performed, searching EMBASE, Web of Science, and Scopus for studies published up to July 1, 2020 and reported following PRISMA guidelines. Pooled analysis was estimated using the Mantel-Haenszel method and a random-effects model. A sub-analysis of the pooled data for each morbidity was performed and demonstrated in forest plots.

Results

Patients with postsurgical chronic HypoPT had a high risk of cardiac morbidities [odds ratio (OR) =1.43; 95% confidence interval (95% CI): 1.21 to 1.70; P<0.001] in the absence of elevated risk of cardiac arrhythmias (OR =1.35, 95% CI: 0.96 to 1.79, P=0.08). Analysis also showed higher odds of developing renal disease (OR =4.85, 95% CI: 3.54 to 6.67, P<0.001), renal stones (OR =3.86, 95% CI: 1.81 to 8.23, P<0.001), seizures (OR =2.41, 95% CI: 1.66 to 3.5, P<0.001), mental health problems (OR =1.46, 95% CI: 1.21 to 1.77, P<0.001), and infections (OR =1.51, 95% CI: 1.28 to 1.78, P<0.001). Conversely, HypoPT has no effect on mortality risk (OR =1.19, 95% CI: 0.96 to 1.49, P=0.12).

Conclusions

Postsurgical HypoPT patients are vulnerable to a variety of medical and psychiatric diseases. This meta-analysis should guide surgeons in preoperative counseling and postoperative care for patients undergoing anterior neck surgeries.

[The Russian registry of chronic hypoparathyroidism and clinical decision support system integration]

According to available research, chronic hypoparathyroidism is a relatively rare disease characterized by low serum calcium levels and the absence or deficiency of parathyroid hormone. The chronic course of the disease is associated with the multicomponent medical therapy, careful dynamic monitoring to reduce the risks of various complications in different organs and systems as well as disability and mortality.The Russian registry of patients with chronic postsurgical and nonsurgical hypoparathyroidism has started its work in 2020, based on data of the Endocrinology Research Centre. The main goals of the Registry are the assessment of the actual prevalence, incidence of hypoparathyroidism, the key epidemiological characteristics, the analysis of the clinical features and medical therapy of chronic hypoparathyroidism in Russian Federation.This article covers all objectives of this project, the methodology for maintaining the registry of chronic postsurgical and nonsurgical hypoparathyroidism, the analytical possibilities of its use, including the integration of a decision support system designed to help specialists in real clinical practice follow the algorithms for diagnosis and treatment of the disease, approved by clinical guidelines.The registry of chronic postsurgical and nonsurgical hypoparathyroidism is located on a single platform for the registers of endocrinopathies, regulated by the Endocrinology Research Centre (http://gipopt.clin-reg.ru/).

Risk of Cardiovascular Conditions in Patients with Chronic Hypoparathyroidism: A Retrospective Cohort Study

Introduction

In patients with chronic hypoparathyroidism disordered calcium homeostasis has been associated with risk of cardiovascular diseases, including cardiomyopathy, congestive heart failure, and arrhythmia; however, larger-scale studies are needed to examine these risks. This study evaluated the risk of cardiovascular conditions among patients with chronic hypoparathyroidism.

Methods

Adults with and without chronic hypoparathyroidism were selected from a medical insurance claims database in the USA from January 2007 to June 2017, and were followed for up to 5 years. Associations between chronic hypoparathyroidism and incident atrial fibrillation (AF), tachyarrhythmia, myocardial infarction (MI), coronary artery disease (CAD), heart failure (HF), stroke, cerebrovascular disease, peripheral vascular disease (PVD), and a combined cardiovascular endpoint of cerebrovascular disease, CAD, HF, and PVD were compared between cohorts using Kaplan–Meier analyses and unadjusted and adjusted Cox proportional hazards models.

Results

In 8097 patients with chronic hypoparathyroidism compared with 40,485 patients without, respectively, mean ± SD ages were 58.6 ± 16.3 and 47.3 ± 18.0 years, 76.2% and 54.4% were female, and 19.4% and 9.5% had the combination of cardiovascular findings at baseline. In adjusted analyses, patients with chronic hypoparathyroidism had significantly higher risk (adjusted hazard ratio and 95% confidence interval) of incident AF (1.72; 1.51–1.97), tachyarrhythmia (1.68; 1.32–2.14), MI (1.18; 1.01–1.38), CAD (1.39; 1.26–1.54), HF (1.64; 1.46–1.84), stroke (1.45; 1.31–1.62), cerebrovascular disease (1.48; 1.34–1.62), PVD (1.66; 1.51–1.81), and combined cardiovascular endpoint (1.63; 1.52–1.75), all P < 0.001 except P = 0.036 for MI, compared with patients without chronic hypoparathyroidism.

Conclusions

This large retrospective cohort study showed that chronic hypoparathyroidism was associated with increased risk of incident cardiovascular conditions and arrhythmias. Results should be evaluated in light of limitations inherent to claims database analyses. Further studies are warranted to investigate reasons for these risks and to develop strategies for reducing cardiovascular conditions in patients with chronic hypoparathyroidism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01787-7.

Five-year Estimated Glomerular Filtration Rate in Patients With Hypoparathyroidism Treated With and Without rhPTH(1-84)

CONTEXT

Chronic hypoparathyroidism (HypoPT) is conventionally managed with oral calcium and active vitamin D. Recombinant human parathyroid hormone (1-84) (rhPTH[1-84]) is a therapy targeting the pathophysiology of HypoPT by replacing parathyroid hormone.

OBJECTIVE

To compare changes in the estimated glomerular filtration rate (eGFR) in patients with chronic HypoPT receiving or not receiving rhPTH(1-84) during a 5-year period.

DESIGN/SETTING

A retrospective analysis of patients with chronic HypoPT treated with or without rhPTH(1-84).

PATIENTS

Sixty-nine patients with chronic HypoPT from 4 open-label, long-term trials (NCT00732615, NCT01268098, NCT01297309, and NCT02910466) composed the rhPTH(1-84) cohort and 53 patients with chronic HypoPT not receiving rhPTH(1-84) from the Geisinger Healthcare Database (01/2004-06/2016) composed the historical control cohort.

INTERVENTIONS

The rhPTH(1-84) cohort (N = 69) received rhPTH(1-84) therapy; the historical control cohort (N = 53) did not receive rhPTH(1-84).

MAIN OUTCOME MEASURES

Changes in eGFR from baseline during a 5-year follow-up were examined in multivariate regression analyses.

RESULTS

At baseline, demographic characteristics and eGFR were similar between cohorts, though the proportions with diabetes and cardiac disorders were lower in the rhPTH(1-84) cohort. At the end of follow-up, mean eGFR increased by 2.8 mL/min/1.73 m2 in the rhPTH(1-84) cohort, while mean eGFR fell by 8.0 mL/min/1.73 m2 in the control cohort. In the adjusted model, the difference in the annual eGFR change between the rhPTH(1-84) cohort and the control cohort was 1.7 mL/min/1.73 m2 per year (P = 0.009).

CONCLUSIONS

Estimated glomerular filtration rate was preserved for over 5 years among patients with chronic HypoPT receiving rhPTH(1-84) treatment, contrasting with an eGFR decline among those not receiving rhPTH(1-84).

The Effect of Admission Serum Magnesium on the Acute Kidney Injury Among Patients with Malignancy

Purpose

This study aimed to explore the relationship between serum magnesium (Mg) levels and incidence of acute kidney injury (AKI) in patients with malignancy.

Patients and Methods

Hospitalized patients with malignancy between October 1, 2014 and September 30, 2015 in Zhongshan Hospital were recruited. All relevant data were extracted from the electronic database.

Results

All 99,845 patients were enrolled and 16,082 eligible patients were divided into three groups according to admission serum Mg levels in this study. Among them, 2383 (14.8%) cases were diagnosed as AKI. The incidence of AKI showed a V trend with the increase of serum Mg level. The effect of low serum Mg level on the onset of AKI seems to be greater than high serum Mg level. Patients with low serum Mg level spent a longer time in the hospital than those with normal serum Mg level and high serum Mg level. Further, multivariate logistic regression model was used to assess the importance of serum Mg level to influence AKI incidence. There was a higher AKI incidence in patients with magnesium level 0.66mmol/L or less (aOR=2.438, 95% CI=1.696, 3.505).

Conclusion

Low serum Mg level might be a independent risk factor for AKI in patients with malignancy. Appropriate clinical intervention for serum Mg disorder may contribute to decreasing the incidence of AKI and the possibility of poor outcomes in cancer patients.

Characteristics of hypoparathyroidism in Colombia: data from a single center in the city of Medellín

OBJECTIVE

Hypoparathyroidism is a rare condition, whose most common etiology is complications of neck surgery. The aim of the study was to identify the clinical and biochemical profile of the patients with diagnosis of hypoparathyroidism, including the frequency of symptoms, clinical signs, long-term complications and disease control. Additionally, the study sought to know what the medication profile was, and the doses required by the patients.

SUBJECTS AND METHOD

A retrospective cohort study was conducted wherein all patients with ICD-10 codes associated with hypoparathyroidism between 2011 and 2018 at the Hospital Universitario San Vicente Fundación were included. We investigated the etiology of the disease; biochemical profile including lowest serum calcium, highest serum phosphorus, 25OHD levels, calciuria and calcium/phosphorus product; medication doses, disease control, and presence of complications, especially renal and neurologic complications were also evaluated.

RESULTS

The cohort included 108 patients (99 women/9 men) with a mean age of 51.6 ± 15.6 years. The main etiology was postoperative (93.5%), the dose of elemental calcium received was relatively low (mean 1,164 mg/day), and in only 9.2% of cases more than 2,500 mg/day of elemental calcium was necessary. We were able to evaluate the follow-up in 89 patients, and found that only 57.3% met the criteria for controlled disease.

CONCLUSION

The clinical profile of patients with hypoparathyroidism in our cohort is similar to that described in other international studies, with predominantly postoperative etiology. With standard therapy, only adequate control is achieved in a little more than half of patients. Arch Endocrinol Metab. 2020;64(3):282-9.

Update on hypoparathyroidism

PURPOSE OF REVIEW

Hypoparathyroidism is a rare endocrine disorder characterized by low or insufficient parathyroid hormone (PTH) concentrations leading to hypocalcemia, hyperphosphatemia, and markedly reduced bone turnover. Despite being a rare disease, hypoparathyroidism has a profound impact on affected patients.

RECENT FINDINGS

Recent epidemiologic surveys demonstrate a prevalence of between 5.3 and 40/100 000, confirming the orphan status of this disease. There is a female predominance, and anterior neck surgery is the most common etiology. Recent studies have better elucidated the chronic manifestations of the disease, impacting quality of life and multiple organ systems including the renal, cardiovascular, and skeletal systems. There are now data on longer term use of parathyroid hormone (PTH) and PTH analogs.

SUMMARY

This review focuses on recent contributions to the literature on the prevalence and epidemiology of the disease, risk of chronic manifestations, and treatment with PTH(1-34) and rhPTH(1-84). Further research is needed to determine the pathophysiology of complications in hypoparathyroidism and whether interventions can decrease future risk of these complications. In addition, further data are needed with regards to more physiologic dosing regimens and long-term treatment with PTH and PTH analogs.

[Hypoparathyroidism - un underestimated problem?]

BACKGROUND

Hypoparathyroidism is a rare and disabilitating disorder characterized by hypocalcemia and low parathyroid hormone levels. Most of the cases occur as a result of the removal of parathyroid glands or damage to the glands during neck surgery. More rare causes include nonsurgical causes such as autoimmune or genetic diseases.

METHOD

In this review, a panel of experts presents the current state of diagnosis and therapy of hypoparathyroidism and explains practical aspects of caring for the affected patients.

RESULTS

Common signs and symptoms are abnormal sensations and increased excitability in the lower limbs, paresthesia of perioral areas and nocturnal leg cramps. Renal complications frequently occur, but also basal ganglia calcification. Treatment consists of administration of vitamin D analogs in combination with 0.5-1.0 g calcium daily. An adjunctive treatment with the in April 2017 approved recombinant human parathyroid hormone (1-84) is an option for patients whose hypoparathyroidism is difficult to control by conventional treatment alone. Initially and after dose changes follow-up controls should be performed at least every 2 weeks, in well-controlled patients or in the case of chronic progression every 3-6 months.

Primary hypoparathyroidism accompanied by rhabdomyolysis induced by infection: A case report

BACKGROUND

Primary hypoparathyroidism (HPT) is rarely seen in the clinic, and it can be combined with rhabdomyolysis. There are few reports about this phenomenon. Therefore, it is significant to explore the etiology that is conducive to early diagnosis, timely treatment, and preventing the recurrence.

CASE SUMMARY

A 63-year-old man was admitted to our hospital with a severe upper respiratory tract infection and progressing decreased myodynamia of the lower limbs. Blood tests showed creatine kinase > 32000 U/L, creatinine 207.8 µmol/L, calcium 1.28 mmol/L, myoglobin 558.7 ng/mL, and parathyroid hormone 0 pg/mL. He was diagnosed with primary HPT with rhabdomyolysis, and severe upper respiratory tract infection was considered to be the initial trigger. He responded well to supplementation of intravenous calcium gluconate and oral calcium as well as bedside hemodialysis, fluid hydration, infection control, protecting the liver, etc. Creatine kinase, myoglobin, and serum calcium returned to normal, and muscle strength improved significantly. Symptoms improved after symptomatic treatment.

CONCLUSION

Severe infection should be prevented, which is the key cause of rhabdomyolysis in patients with HPT.

Ventricular Arrhythmia Precipitated by Severe Hypocalcaemia Secondary to Primary Hypoparathyroidism

Hypocalcaemia causes neuromuscular and myocardial symptoms, including QT interval prolongation, and cardiac arrhythmias. Prompt detection and calcium replacement may reverse the pathology, following which the underlying cause should be diagnosed and treated to prevent recurrence. I present the case of a young man presenting with collapse who was found to have sinus rhythm with significant QT interval prolongation on admission electrocardiogram (ECG) associated with profound hypocalcaemia secondary to primary hypoparathyroidism.

Increased mortality and morbidity in patients with chronic hypoparathyroidism: A population-based study

OBJECTIVES

A population-based study was undertaken to determine the mortality and morbidity for people with hypoparathyroidism compared to the general population.

METHODS

In this study, patients identified with chronic hypoparathyroidism using data linkage from regional datasets were compared with five age- and gender-matched controls from the general population. Data from biochemistry, hospital admissions, prescribing and the demographic dataset were linked. Outcomes for mortality and specified conditions were examined for all patients and subdivided into post-surgical and non-surgical cases of hypoparathyroidism.

RESULTS

All patients had an increased risk of epilepsy (HR 1.65 [95% CI 1.12-2.44]) and cataracts (HR 2.10 [1.30-3.39]) but no increased fracture risk. Only non-surgical hypoparathyroid patients also had increased mortality (HR 2.11 [1.49-2.98]), cardiovascular disease (HR 2.18 [1.41-3.39]), cerebrovascular disease (HR 2.95 [1.46-5.97]), infection (HR 1.87 [1.2-2.92]) and mental illness (HR 1.59 [1.21-2.11]). There was an increased risk of renal failure (HR 10.05 [95% CI 4.71-21.43]) during the first 2000 days (5.5 years) of follow-up. Renal failure and death were associated with increasing serum calcium concentrations.

CONCLUSION

Patients with hypoparathyroidism have an increased risk of cataract and epilepsy. Non-surgical hypoparathyroidism is associated with increased mortality and additional morbidities.

Hypoparathyroidism and the Kidney

Hypocalcemia and hyperphosphatemia are the pathognomonic biochemical features of hypoparathyroidism, and result directly from lack of parathyroid hormone (PTH) action on the kidney. In the absence of PTH action, the renal mechanisms transporting calcium and phosphate reabsorption deregulate, resulting in hypocalcemia and hyperphosphatemia. Circulating calcium negatively regulates PTH secretion. Hypocalcemia causes neuromuscular disturbances ranging from epilepsy and tetany to mild paresthesia. Circulating phosphate concentration does not directly regulate PTH secretion. Hyperphosphatemia is subclinical, but chronically promotes ectopic mineralization disease. Vitamin D-thiazide treatment leads to ectopic mineralization and renal damage. PTH treatment has the potential for fewer side effects.

Epidemiology of parathyroid disorders

Parathyroid disorders are not as uncommon as once believed. Both hyper- and hypoparathyroidism are more prevalent in women, but for different reasons. The female preponderance seen in primary hyperparathyroidism may be pathogenically linked, as it is more common after menopause. By contrast, higher prevalence of hypoparathyroidism in women is related to thyroid surgery, which is performed more frequently in women; thus the female to male ratio of hyper- and hypoparathyroidism is about 3:1 and 4:1 respectively. For similar reasons, the mean age of patients with hypoparathyroidism, on average, is a decade lower than that of patients with primary hyperparathyroidism. Furthermore, primary hyperparathyroidism is the third most common endocrine disorder after diabetes and thyroid disorders, but the prevalence of hypoparathyroidism is about 34 fold lower than that of primary hyperparathyroidism. Current epidemiological data is reasonable for primary hyperparathyroidism, but inadequate for hypoparathyroidism. Further concerted efforts should be undertaken to better define the distribution, determinants and disease burden of both disorders in order to prioritize practice guidelines, disease management strategies, and research agendas.

Epidemiology and Complications of Hypoparathyroidism

Until recently, very few studies have described the epidemiology of this rare disorder. Several large population-based studies have recently been published describing the prevalence and incidence of hypoparathyroidism in various countries. Some of these studies have described the epidemiology of both postsurgical and nonsurgical hypoparathyroidism. In addition, a number of studies have now been published describing the prevalence of complications of this disorder. This article summarizes the published medical literature regarding the prevalence and incidence of this disorder, and the risk of known complications of hypoparathyroidism.