Serum calcium levels are associated with cognitive function in hypoparathyroidism: a neuropsychological and biochemical study in an Italian cohort of patients with chronic post-surgical hypoparathyroidism

Evaluation of Compliance With International Guidelines During the Follow-Up of Hypoparathyroidism

Aims: Hypoparathyroidism is a disorder that causes renal complications, bone disease, an increased risk of cardiovascular diseases, neuromuscular complications, and ocular findings. In this study, we aimed to determine how well the existing guidelines were followed in the follow-up of patients with hypoparathyroidism. Materials and Methods: In the endocrinology and metabolism outpatient clinic, routine controls were conducted on patients 18 years of age and older with a diagnosis of hypoparathyroidism between February 2019 and September 2021. These individuals' test findings, imaging, hormones, and additional disorders were assessed. Results: The mean age of 264 patients included in the study was 49.34 ± 12.98 (22-91). Of the patients, 211 (79.9%) were female. Blood biochemistry tests were performed on all patients. Ophthalmological examination was performed in 3% of the patients, brain imaging in 9.8%, renal imaging in 18.6%, and 24-h urinary Ca measurements in 11%. According to the results of the examinations, cataract was found in 2 (0.8%) patients and basal ganglia calcification was found in 4 (1.5%) patients. In addition, nephrocalcinosis or nephrolithiasis was seen in 2 patients (0.8%). Hypercalciuria was defined as a 24-h urinary calcium excretion of > 300 mg/24 h for males and > 250 mg/dL for females and was detected in 12 patients with hypoparathyroidism. Conclusion: In our research, it was discovered that patients with hypoparathyroidism had low compliance rates with the guidelines. We believe that the cause of this is the inability to provide the patients with enough time in intense polyclinic conditions. Given the information gathered from our study, it has been concluded that complication screening in hypoparathyroidism patients is just as crucial as blood tests and that allocating enough time for patients will enhance their follow-up and treatment.

Depression reduces cognitive function partly through effects on BMI and hypertension: a large observational study and Mendelian randomization analysis

BACKGROUND

While abundant evidence suggests a correlation between depression and the risk of cognitive impairments, the causal relationship, as well as the mechanisms mediating this association, remain uncertain.

METHODS

We conducted an observational study within the National Health and Nutrition Examination Survey (NHANES), simultaneously employing weighted multivariable-adjusted linear regression to explore the association between them. Subsequently, Mendelian randomization analysis was employed to investigate the causal relationship between them as well as the mediating effects.

RESULTS

The observational analysis of NHANES data indicates that depression is independently associated with cognitive function. Regarding MR, genetically predicted depression is causally related to cognitive function in the IVW method (OR 0.33, 95% CI 0.14-0.78, P = 0.012). Furthermore, depression leads to obesity (OR = 1.91, P = 2.53 × 10 - 3) and elevated blood pressure (OR 2.34, P = 3.62 × 10 - 3). Waist circumference (OR = 0.85, P = 3.00 × 10 - 4), BMI (OR = 0.84, P = 1.06 × 10 - 6), and hypertension (OR = 0.95, P = 4.00 × 10 - 3) all contribute to cognitive function. Additionally, there is no causal association between cognitive function and depression (OR 1.00, 95% CI 0.99-1.01, P = 0.559) in reverse Mendelian randomization. Mediation analysis indicates that BMI and hypertension mediate 9.9% and 3.6% of the cognitive function under depression conditions, respectively.

CONCLUSIONS

Our study indicates that depression can lead to obesity and hypertension, which can reduce cognitive function. These findings underscore the importance of timely identification and management of depression in patients with cognitive impairments and suggest that treatments aimed at reducing weight and lowering blood pressure may help prevent cognitive impairment.

Management of autosomal dominant hypocalcemia type 1: Literature review and clinical practice recommendations

PURPOSE

Autosomal Dominant Hypocalcemia type 1 (ADH1), caused by gain-of-function variants in the calcium-sensing receptor (CASR), is characterized by a variable degree of hypocalcemia and hypercalciuria with inappropriately low PTH. The clinical spectrum is broad, ranging from being asymptomatic to presenting with severe clinical features of hypocalcemia and end-organ damage such as nephrolithiasis and intracerebral calcifications. Although the underlying pathophysiology is different, ADH1 patients are often managed as patients with 'classical' primary hypoparathyroidism, possibly leading to (exacerbation of) hypercalciuria. New treatments such as PTH analogues and calcilytics directly targeting the CASR are in the pipeline. Specific clinical guidance for treatment and monitoring of ADH1 patients is lacking. The purpose of this study is to provide a literature review on management of ADH1, including new therapies, and to formulate practice recommendations.

METHODS

We searched for articles and ongoing clinical trials regarding management of ADH1.

RESULTS

Forty articles were included. First we review the conventional treatment of ADH1, focusing on active vitamin D, calcium supplements, thiazide diuretics, phosphorus binders and dietary recommendations. In a second part we give an overview of studies with emerging treatments in ADH1: PTH analogues (PTH1-34, rhPTH1-84, TransCon PTH and others) and calcilytics (preclinical studies and clinical trials). In a third part we discuss literature findings regarding monitoring of ADH1 patients. Finally, we formulate clinical practice recommendations.

CONCLUSION

We provide an overview of conventional and new treatments for ADH1 patients. Based on these data, we propose practical recommendations to assist clinicians in the management of ADH1 patients.

Hypoparathyroidism: changes in brain structure, cognitive impairment, and reduced quality of life

Hypoparathyroidism (HypoPT) is a disease with no/or inadequate production/secretion of parathyroid hormone (PTH) from the parathyroid glands. Low levels of PTH result in hypocalcemia, which is often treated with calcium supplementation and active vitamin-D analogs. However, increasing evidence suggests that HypoPT has a profound impact on several organ systems. Quality of life (QOL) is reduced in patients with HypoPT, partly due to symptoms related to the central nervous system-including subjective feelings of confusion, a reduced ability to focus and think clearly (ie, "brain fog"). However, the extent to which these complex symptoms relate to quantifiable changes in patients' cognitive performance as determined by neuropsychological tests remains unclear. The brains of HypoPT patients may reveal tissue calcifications, but the extent to which long-term brain exposure to low PTH levels and/or changing calcium levels affects brain structure is unknown. In a cross-sectional study, we investigated PTH levels, QOL, cognitive impairment, and brain structure in well-treated post-surgical and non-surgical hypoparathyroid patients compared with healthy controls. QOL was quantified by the SF36v2, WHO-5 wellbeing Index, and two disease-specific questionnaires-the HPQ28 and Hypoparathyroidism Symptom Diary. Cognitive functions were tested using comprehensive neuropsychological. Brain structure was quantified by morphological analyses of magnetic resonance imaging images. We found reduced QOL and cognitive functioning in terms of processing speed, executive functions, visual memory, and auditory memory in HypoPT. Furthermore, HypoPT revealed a reduced volume of the hippocampus-and the size of the thalamus in postsurgical patients was associated with the disease duration. Importantly, patients reporting severe brain fog had a smaller hippocampus than those with less brainfog. HypoPT is associated with quantifiable cognitive deficits and changes in brain structure that align with patient symptoms. Our exploratory study warrants further studies of the neurobiological impact of PTH and of the impact of PTH replacements therapy on patients' cognitive functioning.

Presentation of hypoparathyroidism in Italy: a nationwide register-based study

PURPOSE

We sought to assess the clinical presentation of hypoparathyroidism (HypoPT) in Italy.

METHODS

We performed a nationwide study retrieving data from the hospital discharge ICD-9 codes database of the Italian Health Ministry, from 2007 through 2017. The codes corresponding to diagnosis of cardiovascular disease, cancer, infection, renal failure, psychiatric disease, upper airway tract infection and pneumonia, seizures, nephrolithiasis, cognitive impairment, cerebral calcifications, skin disorders, fracture, and cataract were retrieved when associated with the diagnosis of HypoPT (252.1). We excluded codes corresponding to diagnoses of cancer of the neck region. In-hospital mortality rate was calculated. We retrieved the same data from an age- and sex-matched non-HypoPT control population.

RESULTS

Fourteen thousand five hundred seventy-nine hospitalizations for HypoPT and controls were analyzed. Hospitalization for cardiovascular disease, cancer, infection, renal failure, seizures, nephrolithiasis, cerebral calcifications (p < 0.0001), and cognitive impairment (p < 0.05) were more common in HypoPT compared to controls. Mean age of HypoPT with cardiovascular disease, cancer, and renal failure was younger compared to controls (p < 0.0001). The OR of hospitalization for cardiovascular disease, cancer, renal failure, seizures (OR 2, 40, 48  and 1.6, respectively), and nephrolithiasis (OR 1.6) were significant in HypoPT compared to non-HypoPT. The OR of hospitalization for infection and cognitive impairment were significant only in HypoPT women (OR 1.3 and 2.3, respectively). In-hospital mortality rate was lower in HypoPT vs controls (0.5% and 3.7%; p < 0.0001).

CONCLUSION

Hospitalizations for cardiovascular disease, cancer, and renal failure are more prevalent and occur at a younger age in HypoPT vs non-HypoPT. Hospitalizations for seizures and nephrolithiasis are frequent in HypoPT; those for infection and cognitive impairment are more common in HypoPT women.

Features of patients and fracture risk in hypoparathyroidism; a single center study

PURPOSE

Patients with hypoparathyroidism (hypoPT) have low bone turnover and high bone mineral density (BMD). However, data on fracture risk are conflicting. The objectives of this study were: 1. To describe clinical/biochemical characteristics of hypoPT patients followed at a single medical center. 2. To identify postsurgical hypoPT patients and investigate their fracture rate compared with gender/age-matched post-surgical normocalcemic patients.

METHODS

Retrospective analysis of patient's medical records treated at the tertiary medical center in 2010-2021 identified by computerized medical database search.

RESULTS

The cohort included 133 patients (91% women, mean age 64 ± 13 years) of whom 105 (79%) had post-thyroidectomy hypoparathyroidism and the remainder had an autoimmune/idiopathic/other etiology. Mean follow-up time was 21 ± 12 and 27 ± 12 years, respectively. The control group included 142 post-thyroidectomy patients without hypoparathyroidism. Patients in the postsurgical hypoparathyroidism group were older and had higher calcium and PTH levels at diagnosis than the non-surgical hypoPT patients. Comparing the postsurgical hypoPT and postsurgical normocalcemic control patients revealed a significantly higher BMD in the hypoPT group. Yet, fracture rates were 31% in the postsurgical hypoparathyroidism group and 21% in the control group (P = 0.1) over a similar median follow-up period (17 and 18.4 years, respectively). In both groups the most common fracture site was the spine (50% and 70%, respectively; p = 0.33), mainly nonclinical morphometric fractures. Higher phosphorus blood level was associated with increased fracture risk.

CONCLUSIONS

The relatively high BMD in patients with postsurgical hypoparathyroidism is not associated with lower fracture risk. Silent morphometric fractures are quite common in this group of patients.

Performance in Behavioral Testing in an Animal Model of Post-Surgical Hypoparathyroidism

BACKGROUND

Hypoparathyroidism (HypoPT) is characterized by hypocalcemia and undetectable/inappropriately low PTH. Post-surgical HypoPT (PS-HypoPT) is the most common cause. Patients with PS-HypoPT present neuropsychological symptoms, probably due to the PTH deprivation in the central nervous system (CNS). However, these mechanisms are still not elucidated. The aim of this study was to evaluate the effects of PTH deprivation on CNS in an animal model of PS-HypoPT via a cognitive/behavioral assessment approach.

METHODS

A surgical rat model of PS-HypoPT was obtained and treated with calcium to maintain normocalcemia. Twenty PS-HypoPT rats and twenty sham-operated controls (Crl) underwent behavioral testing in a Morris Water Maze (MWM), Open Field (OF), and Elevated Plus Maze (EPM).

RESULTS

In the MWM, PTx rats showed a higher Escape Latency Time compared to Crl rats (p < 0.05); we observed a statistically significant improvement in the performance (day 1 to 8 p < 0.001), which was less pronounced in PTx group. In the OF test, the time and distance spent in the zone of interest were significantly lower in the PTx group compared with the Crl (p < 0.01 and p < 0.01). In the EPM experiment, the time spent in the close arm was significantly higher in the PTx group compared with the Crl (p < 0.01).

CONCLUSIONS

This animal model of PS-HypoPT shows an impairment in spatial memory, which improved after training, and a marked anxiety-like behavior, resembling the condition of patients with PS-HypoPT. Further studies are needed to elucidate mechanisms.

PTH level might be associated with impaired quality of life in patients with nonsurgical hypoparathyroidism

OBJECTIVE

Nonsurgical hypoparathyroidism (ns-HP) is a rare disease. There are few studies on Quality of Life (QoL) among patients with ns-HP. This study aimed to investigate the QoL among ns-HP patients with regular conventional treatment, and explore the influence factors affecting QoL among these Chinese ns-HP patients.

METHODS

This is a cross-sectional study comparing 101 patients identified as ns-HP and 101 healthy controls. The questionnaires of Short Form 36 Health Survey questionnaire version 2(SF-36v2) were used to evaluate QoL.

RESULTS

Scores of all eight subdomains of SF-36v2 and physical component scores (PCS), mental component scores (MCS) were significantly lower in the ns-HP group compared with the healthy controls. The indices of all subdomains of SF-36v2 between Q1 (the lowest quartile) and Q4 (the highest quartile) groups were compared, suggesting higher percentages of detectable parathyroid hormone (PTH) before treatment in Q4 group among all QoL indices except two subdomains (physical function and body pain).

CONCLUSION

Both mental and physical QoL were impaired in the ns-HP patients even with regular conventional treatment for hypocalcemia, which were more severe in cases with lower baseline PTH levels.

The Role of the Patient Partnership in Designing Research on Neuropsychiatric Issues in Hypoparathyroidism

Hypoparathyroidism is a rare endocrine disease that is associated with hypocalcemia and insufficient parathyroid hormone (PTH) levels. Neuropsychiatric complaints are common in hypoparathyroidism. Yet there is a large knowledge gap in our understanding of cognitive dysfunction in hypoparathyroidism and partnering with patients is essential for filling this hole. Input from hypoparathyroid patients is needed to define objective, performance-based cognitive impairments. Creating patient advisory boards that provide input for planning clinical trials would enable patient perspectives to be shared. This would ensure that meaningful, standardized neuropsychological instruments that prioritize patients' cognitive concerns are selected. Patient partnership is also needed to understand the wide inter-individual variability of cognitive symptoms in hypoparathyroidism, as well as mechanisms aside from calcium shifts that might explain cognitive symptoms, such as low PTH itself, alterations in brain structure, or other hypoparathyroidism-associated comorbidities. With new PTH replacement therapies on the horizon, patient input about studying how these therapies impact, and maybe even reverse, cognitive impairment will also be critical. Ultimately, the inclusion of patient partners in hypoparathyroidism research will advance the design of neuropsychiatric studies and generate key input for understanding how to reduce the burden of this disease.

Parathyroid Hormone (PTH)-Related Peptides Family: An Intriguing Role in the Central Nervous System

Parathyroid Hormone (PTH) plays a crucial role in the maintenance of calcium homeostasis directly acting on bone and kidneys and indirectly on the intestine. However, a large family of PTH-related peptides exists that exerts other physiological effects on different tissues and organs, such as the Central Nervous System (CNS). In humans, PTH-related peptides are Parathyroid Hormone (PTH), PTH-like hormones (PTHrP and PTHLH), and tuberoinfundibular peptide of 39 (TIP39 or PTH2). With different affinities, these ligands can bind parathyroid receptor type 1 (PTH1R) and type 2 (PTH2R), which are part of the type II G-protein-coupled-receptors (GPCRs) family. The PTH/PTHrP/PTH1R system has been found to be expressed in many areas of the brain (hippocampus, amygdala, hypothalamus, caudate nucleus, corpus callosum, subthalamic nucleus, thalamus, substantia nigra, cerebellum), and literature data suggest the system exercises a protective action against neuroinflammation and neurodegeneration, with positive effects on memory and hyperalgesia. TIP39 is a small peptide belonging to the PTH-related family with a high affinity for PTH2R in the CNS. The TIP39/PTH2R system has been proposed to mediate many regulatory and functional roles in the brain and to modulate auditory, nociceptive, and sexual maturation functions. This review aims to summarize the knowledge of PTH-related peptides distribution and functions in the CNS and to highlight the gaps that still need to be filled.

Vitamin D in hypoparathyroidism: insight into pathophysiology and perspectives in clinical practice

Hypoparathyroidism (HypoPT) is a rare endocrine disorder characterized by the absence or insufficient parathyroid hormone production resulting in chronic hypocalcemia. Complications of HypoPT include perturbation of several target organs. The conventional treatment consists of the administration of active vitamin D, namely calcitriol. Regarding vitamin D status, few data are available, mostly in HypoPT subjects supplemented with parent vitamin D. In addition, perturbation of vitamin D metabolism has been poorly investigated, as well as the contribution of altered vitamin D status on the clinical expression of the disease. The most recent consensus on the management of chronic HypoPT suggests the baseline evaluation of serum 25-hydroxy-vitamin D [25(OH)D] and supplementation with parent vitamin D with the aim to achieve and maintain serum 25(OH)D levels in the range of 30-50 ng/mL. The rationale for using supplementation with parent vitamin D (either ergocalciferol or cholecalciferol) in HypoPT would be to provide sufficient 25(OH)D substrate to the residual 1-α-hydroxylase activity, thus ensuring its conversion to active vitamin D in renal and extra-renal tissues. More data from experimental and clinical studies are needed for better assessing how these mechanisms may significantly influence metabolic control in HypoPT and eventually skeletal and extra-skeletal manifestation of the disease. Finally, future data will clarify how the currently available parent vitamin D compounds (ergocalciferol, cholecalciferol, calcifediol) would perform in addressing these specific issues.