Extended Treatment With Recombinant Human Parathyroid Hormone (1-84) in Adult Patients With Chronic Hypoparathyroidism.

OBJECTIVE: Recombinant human parathyroid hormone (1-84) (rhPTH[1-84]) is efficacious in patients with hypoparathyroidism but additional data supporting its prolonged use are needed. We evaluated whether efficacy, safety, and tolerability are maintained during long-term rhPTH(1-84) treatment of patients with chronic hypoparathyroidism. METHODS: This was a phase 4, single-center, open-label, single-arm, 3-year extension (NCT02910466) of the phase 3 Hypo Extended (HEXT) study (NCT01199614). Patients self-administered rhPTH(1-84) once daily by subcutaneous injection, with doses individualized based on clinical parameters. Albumin-adjusted serum calcium levels (primary outcome measure), other disease biomarkers, health-related quality of life, and safety of rhPTH(1-84) were assessed using descriptive statistics. RESULTS: All patients (n = 39) had been exposed to rhPTH(1-84) (mean exposure [SD] 8.5 [3.5] years) before the start of the study, resulting in a mean exposure of 10.8 years including the present study. Mean patient age was 51.9 years, 79.5% were female, and 97.4% were White. Mean albumin-adjusted serum calcium concentrations were within the target range, and mean serum phosphate, serum calcium-phosphate product, and 24-hour urinary calcium excretion levels were within reference ranges at end of treatment. Mean doses of supplemental calcium and active vitamin D were maintained throughout the study. Bone turnover marker levels were maintained from baseline to end of treatment. No clinically relevant changes in bone mineral density were observed. Patient-reported health-related quality-of-life scores were generally maintained throughout the study. Four adverse events were considered treatment related and no new safety signals were identified. CONCLUSION: The effects of rhPTH(1-84) on biochemical, skeletal, and health-related quality-of-life parameters did not wane with extended use.

Reference Intervals for Bone Impact Microindentation in Healthy Adults: A Multi-Centre International Study.

Impact microindentation (IMI) is a novel technique for assessing bone material strength index (BMSi) in vivo, by measuring the depth of a micron-sized, spherical tip into cortical bone that is then indexed to the depth of the tip into a reference material. The aim of this study was to define the reference intervals for men and women by evaluating healthy adults from the United States of America, Europe and Australia. Participants included community-based volunteers and participants drawn from clinical and population-based studies. BMSi was measured on the tibial diaphysis using an OsteoProbe in 479 healthy adults (197 male and 282 female, ages 25 to 98 years) across seven research centres, between 2011 and 2018. Associations between BMSi, age, sex and areal bone mineral density (BMD) were examined following an a posteriori method. Unitless BMSi values ranged from 48 to 101. The mean (± standard deviation) BMSi for men was 84.4 ± 6.9 and for women, 79.0 ± 9.1. Healthy reference intervals for BMSi were identified as 71.0 to 97.9 for men and 59.8 to 95.2 for women. This study provides healthy reference data that can be used to calculate T- and Z-scores for BMSi and assist in determining the utility of BMSi in fracture prediction. These data will be useful for positioning individuals within the population and for identifying those with BMSi at the extremes of the population.

MC4R-dependent suppression of appetite by bone-derived lipocalin 2.

Bone has recently emerged as a pleiotropic endocrine organ that secretes at least two hormones, FGF23 and osteocalcin, which regulate kidney function and glucose homeostasis, respectively. These findings have raised the question of whether other bone-derived hormones exist and what their potential functions are. Here we identify, through molecular and genetic analyses in mice, lipocalin 2 (LCN2) as an osteoblast-enriched, secreted protein. Loss- and gain-of-function experiments in mice demonstrate that osteoblast-derived LCN2 maintains glucose homeostasis by inducing insulin secretion and improves glucose tolerance and insulin sensitivity. In addition, osteoblast-derived LCN2 inhibits food intake. LCN2 crosses the blood-brain barrier, binds to the melanocortin 4 receptor (MC4R) in the paraventricular and ventromedial neurons of the hypothalamus and activates an MC4R-dependent anorexigenic (appetite-suppressing) pathway. These results identify LCN2 as a bone-derived hormone with metabolic regulatory effects, which suppresses appetite in a MC4R-dependent manner, and show that the control of appetite is an endocrine function of bone.

Corrigendum: MC4R-dependent suppression of appetite by bone-derived lipocalin 2.

This corrects the article DOI: 10.1038/nature21697.

Vitamin D Status and COVID-19 Clinical Outcomes in Hospitalized Patients.

Context: Populations severely affected by COVID-19 are also at risk for vitamin D deficiency. Common risk factors include older age, chronic illness, obesity, and non-Caucasian race. Vitamin D deficiency has been associated with risk for respiratory infections and failure, susceptibility and response to therapy for enveloped virus infection, and immune-mediated inflammatory reaction.Objective: To test the hypothesis that 25-hydroxyvitamin D[25(OH)D] deficiency is a risk factor for severity of COVID-19 respiratory and inflammatory complications.Design: We examined the relationship between prehospitalization 25(OH)D levels (obtained 1-365 days prior to admission) and COVID-19 clinical outcomes in 700 COVID-19 positive hospitalized patients.Primary Outcomes: Discharge status, mortality, length of stay, intubation status, renal replacement.Secondary Outcomes: Inflammatory markers.Results: 25(OH)D levels were available in 93 patients [25(OH)D:25(IQR:17-33)ng/mL]. Compared to those without 25(OH)D levels, those with measurements did not differ in age, BMI or distribution of sex and race, but were more likely to have comorbidities. Those with 25(OH)D < 20 ng/mL (n = 35) did not differ from those with 25(OH)D ≥ 20 ng/mL in terms of age, sex, race, BMI, or comorbidities. Low 25(OH)D tended to be associated with younger age and lower frequency of preexisting pulmonary disease. There were no significant between-group differences in any outcome. Results were similar in those ≥50 years, in male/female-only cohorts, and when differing 25(OH)D thresholds were used (<15 ng/mL and <30 ng/mL). There was no relationship between 25(OH)D as a continuous variable and any outcome, even after controlling for age and pulmonary disease.Conclusions: These preliminary data do not support a relationship between prehospitalization vitamin D status and COVID-19 clinical outcomes.

In Vivo Precision of Digital Topological Skeletonization Based Individual Trabecula Segmentation (ITS) Analysis of Trabecular Microstructure at the Distal Radius and Tibia by HR-pQCT.

Trabecular plate and rod microstructure plays a dominant role in the apparent mechanical properties of trabecular bone. With high-resolution computed tomography (CT) images, digital topological analysis (DTA) including skeletonization and topological classification was applied to transform the trabecular three-dimensional (3D) network into surface and curve skeletons. Using the DTA-based topological analysis and a new reconstruction/recovery scheme, individual trabecula segmentation (ITS) was developed to segment individual trabecular plates and rods and quantify the trabecular plate- and rod-related morphological parameters. High-resolution peripheral quantitative computed tomography (HR-pQCT) is an emerging in vivo imaging technique to visualize 3D bone microstructure. Based on HR-pQCT images, ITS was applied to various HR-pQCT datasets to examine trabecular plate- and rod-related microstructure and has demonstrated great potential in cross-sectional and longitudinal clinical applications. However, the reproducibility of ITS has not been fully determined. The aim of the current study is to quantify the precision errors of ITS plate-rod microstructural parameters. In addition, we utilized three different frequently used contour techniques to separate trabecular and cortical bone and to evaluate their effect on ITS measurements. Overall, good reproducibility was found for the standard HR-pQCT parameters with precision errors for volumetric BMD and bone size between 0.2%-2.0%, and trabecular bone microstructure between 4.9%-6.7% at the radius and tibia. High reproducibility was also achieved for ITS measurements using all three different contour techniques. For example, using automatic contour technology, low precision errors were found for plate and rod trabecular number (pTb.N, rTb.N, 0.9% and 3.6%), plate and rod trabecular thickness (pTb.Th, rTb.Th, 0.6% and 1.7%), plate trabecular surface (pTb.S, 3.4%), rod trabecular length (rTb.ℓ, 0.8%), and plate-plate junction density (P-P Junc.D, 2.3%) at the tibia. The precision errors at the radius were similar to those at the tibia. In addition, precision errors were affected by the contour technique. At the tibia, precision error by the manual contour method was significantly different from automatic and standard contour methods for pTb.N, rTb.N and rTb.Th. Precision error using the manual contour method was also significantly different from the standard contour method for rod trabecular number (rTb.N), rod trabecular thickness (rTb.Th), rod-rod and plate-rod junction densities (R-R Junc.D and P-R Junc.D) at the tibia. At the radius, the precision error was similar between the three different contour methods. Image quality was also found to significantly affect the ITS reproducibility. We concluded that ITS parameters are highly reproducible, giving assurance that future cross-sectional and longitudinal clinical HR-pQCT studies are feasible in the context of limited sample sizes.

Bone cells and bone turnover in diabetes mellitus.

Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due, at least in part, to altered bone remodeling and bone cell function in diabetes. Circulating biochemical markers of bone formation, including P1NP, osteocalcin and bone-specific alkaline phosphatase have been found to be decreased in type 2 diabetes (T2D) and may be predictive of fractures independently of bone mineral density (BMD). These findings have been corroborated by preliminary histomorphometric data. Reductions in the bone resorption marker serum CTx in T2D have also been reported. Serum sclerostin levels have been found to be increased in T2D and appear to be predictive of fracture risk independent of BMD. Other factors such as bone marrow fat saturation, advanced glycation endproduct (AGE) accumulation, and microarchitectural changes might also relate to bone cell function and fracture risk in diabetes.

Magnetic resonance imaging-measured bone marrow adipose tissue area is inversely related to cortical bone area in children and adolescents aged 5-18 years.

Previous studies have shown an inverse correlation between bone marrow adipose tissue and bone mineral density in cancellous bone; however, such relationships in cortical bone are less studied, especially in children. A total of 185 healthy children and adolescents (76 females and 109 males, aged 5-18 years) were included in this study. Right femoral bone marrow adipose tissue area (BMA), right femoral cortical bone area (CBA), subcutaneous adipose tissue, visceral adipose tissue, and skeletal muscle were accessed by whole-body magnetic resonance imaging. In regression analysis with CBA as the dependent variable and BMA as the independent variable, BMA negatively contributed to CBA after adjusting for weight and total body fat or subcutaneous adipose tissue, visceral adipose tissue, and skeletal muscle (ß = -0.201 to -0.272, p < 0.001). These results suggest an inverse relationship between BMA and CBA in children and adolescents after adjustment of body weight or body composition. The data support the hypothesis that a competitive relationship exists between bone and marrow fat in cortical bone and is consistent with a similar finding in cancellous bone in previous studies. Future research is needed to clarify the role of marrow fat in childhood fractures that are related to cortical bone quality.

Palopegteriparatide Treatment Improves Renal Function in Adults with Chronic Hypoparathyroidism: 1-Year Results from the Phase 3 PaTHway Trial.

INTRODUCTION: Individuals with chronic hypoparathyroidism managed with conventional therapy (active vitamin D and calcium) have an increased risk for renal dysfunction versus age- and sex-matched controls. Treatments that replace the physiologic effects of parathyroid hormone (PTH) while reducing the need for conventional therapy may help prevent a decline in renal function in this population. This post hoc analysis examined the impact of palopegteriparatide treatment on renal function in adults with chronic hypoparathyroidism. METHODS: PaTHway is a phase 3 trial of palopegteriparatide in adults with chronic hypoparathyroidism that included a randomized, double-blind, placebo-controlled 26-week period followed by an ongoing 156-week open-label extension (OLE) period. Changes in renal function over 52 weeks (26 weeks blinded + 26 weeks OLE) were assessed using estimated glomerular filtration rate (eGFR). A subgroup analysis was performed with participants stratified by baseline eGFR < 60 or ≥ 60 mL/min/1.73 m2. RESULTS: At week 52, over 95% (78/82) of participants remained enrolled in the OLE and of those, 86% maintained normocalcemia and 95% achieved independence from conventional therapy (no active vitamin D and ≤ 600 mg/day of calcium), with none requiring active vitamin D. Treatment with palopegteriparatide over 52 weeks resulted in a mean (SD) increase in eGFR of 9.3 (11.7) mL/min/1.73 m2 from baseline (P < 0.0001) and 43% of participants had an increase ≥ 10 mL/min/1.73 m2. In participants with baseline eGFR < 60 mL/min/1.73 m2, 52 weeks of treatment with palopegteriparatide resulted in a mean (SD) increase of 11.5 (11.3) mL/min/1.73 m2 (P < 0.001). One case of nephrolithiasis was reported for a participant in the placebo group during blinded treatment; none were reported through week 52 with palopegteriparatide. CONCLUSION: In this post hoc analysis of the PaTHway trial, palopegteriparatide treatment was associated with significantly improved eGFR at week 52 in addition to previously reported maintenance and normalization of serum and urine biochemistries. Further investigation of palopegteriparatide for the preservation of renal function in hypoparathyroidism is warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT04701203.

Chronic hypoparathyroidism is caused by inadequate parathyroid hormone (PTH) levels. Hypoparathyroidism is managed with conventional therapy (active vitamin D and calcium), but over time the disease itself and conventional therapy can increase the risk of medical complications including kidney problems. This study looked at how a new treatment for chronic hypoparathyroidism, palopegteriparatide (approved in the European Union under the brand name YORVIPATH^®), affects kidney function in adults in the PaTHway clinical trial. Participants were randomly assigned to receive palopegteriparatide or a placebo injection once daily along with conventional therapy. For both groups, clinicians used a protocol to eliminate conventional therapy while maintaining normal blood calcium levels. After 26 weeks, participants on placebo switched to palopegteriparatide. Ninety-five percent of participants were still enrolled in the PaTHway trial after 52 weeks. Of those, 86% had normal blood calcium levels and 95% did not need conventional therapy (not taking vitamin D and not taking therapeutic doses of calcium [> 600 mg/day]). After 52 weeks of treatment with palopegteriparatide, significant improvements were seen in a measure of kidney function called estimated glomerular filtration rate (eGFR). Improvements in eGFR from the beginning of the trial to week 52 were considered clinically meaningful for over 57% of participants. In participants with impaired kidney function at the beginning of the trial, eGFR improvements were even greater, and 74% of participants had a clinically meaningful improvement. These results suggest that palopegteriparatide treatment may be beneficial for kidney function in adults with chronic hypoparathyroidism, especially those with impaired kidney function.

Pancreas-kidney transplantation is associated with reduced fracture risk compared with kidney-alone transplantation in men with type 1 diabetes.

Both type 1 diabetes mellitus and end-stage renal disease are associated with increased fracture risk, likely because of metabolic abnormalities that reduce bone strength. Simultaneous pancreas-kidney transplantation is a treatment of choice for patients with both disorders, yet the effects of simultaneous pancreas-kidney and kidney transplantation alone on post-transplantation fracture risk are unknown. From the United States Renal Data System, we identified 11,145 adults with type 1 diabetes undergoing transplantation, of whom 4933 had a simultaneous pancreas-kidney transplant and 6212 had a kidney-alone transplant between 2000 and 2006. Post-transplantation fractures resulting in hospitalization were identified from discharge codes. Time to first fracture was modeled and propensity score adjustment was used to balance covariates between groups. Fractures occurred in significantly fewer (4.7%) of pancreas-kidney compared with kidney-alone transplant (5.9%) cohorts. After gender stratification and adjustment for fracture covariates, pancreas-kidney transplantation was associated with a significant 31% reduction in fracture risk in men (hazard risk 0.69). Older age, white race, prior dialysis, and pre-transplantation fracture were also associated with increased fracture risk. Prospective studies are needed to determine the gender-specific mechanisms by which pancreas-kidney transplantation reduces fracture risk in men.

Nontraditional manifestations of primary hyperparathyroidism.

Classical primary hyperparathyroidism (PHPT) was previously a multisystemic symptomatic disorder not only with overt skeletal and renal complications but also with neuropsychological, cardiovascular, gastrointestinal, and rheumatic effects. The presentation of PHPT has evolved, and today most patients are asymptomatic. Osteitis fibrosa cystica is rarely seen today, and nephrolithiasis is less common. Gastrointestinal and rheumatic symptoms are not part of the clinical spectrum of modern PHPT. It remains unclear whether neuropsychological symptoms and cardiovascular disease, neither of which are currently indications for recommending parathyroidectomy (PTX), are part of the modern phenotype of PHPT. A number of observational studies suggest that mild PHPT is associated with depression, decreased quality of life, and changes in cognition, but limited data from randomized controlled trials (RCTs) have not indicated consistent benefits after surgery. The increased cardiovascular morbidity and mortality in severe PHPT has not been definitively demonstrated in mild disease, although there is some evidence for more subtle cardiovascular abnormalities, such as increased vascular stiffness, among others. Results from observational studies that have assessed the effect of PTX on cardiovascular health have been conflicting. The single RCT in this area did not demonstrate that PTX was beneficial. Despite recent progress in these areas, more data from rigorously designed studies are needed to better inform the clinical management of patients with asymptomatic PHPT.

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.

Psychometric Analysis of the Patient-Reported Hypoparathyroidism Symptom Diary Symptom Subscale Using Data from Two Clinical Trials.

Purpose: The hypoparathyroidism symptom diary (HypoPT-SD) is a disease-specific patient-reported outcome (PRO) tool comprising a 7-item symptom subscale, a 4-item impact subscale and 1-item anxiety, and sadness or depression components. This analysis assessed the psychometric properties of the HypoPT-SD symptom subscale scores using data from two open-label, single arm, Phase 4 studies (Study 402 and Study 404). Patients and Methods: Eligible patients were aged 18 years or older with a confirmed diagnosis of hypoparathyroidism. All patients received recombinant human parathyroid hormone (1-84) during the analysis period. Scores were recorded at baseline, and at months 6, 30 and 36 (end of treatment [EOT]) in Study 402, and at baseline and week 52 (EOT) in Study 404. The structure of the HypoPT-SD Symptom subscale was analyzed by measuring correlations between pairs of item scores; internal consistency and reliability were evaluated using Cronbach's coefficient α; test-retest reliability was assessed using intraclass correlation; and construct validity was determined by performing correlational analyses between scores recorded using the HypoPT-SD and those for other conceptually similar PRO tools. Results: A total of 60 patients were included in the analysis. Inter-item pairwise correlations were strong for all but 5 of the item pairs analysed. Cronbach's α values for the HypoPT-SD Symptom subscale were 0.88 using data from Study 402 and 0.92 using data from Study 404. In general, the HypoPT-SD Symptom subscale scores had moderate or strong correlations with scores recorded using PRO tools. Intraclass correlation coefficients exceeded 0.70 using test-retest data from all patients in Study 402 and from a subgroup of patients with stable disease from Study 404. Conclusion: This analysis demonstrated the test-retest reliability, internal consistency and construct validity of the HypoPT-SD using data from longitudinal prospective studies and supports the use of the HypoPT-SD in future clinical studies.

The Clinical and Skeletal Effects of Long-Term Therapy of Hypoparathyroidism With rhPTH(1-84).

Hypoparathyroidism (HypoPT) is a disorder characterized by hypocalcemia, low or absent parathyroid hormone (PTH) levels, reduced bone remodeling, and high areal bone mineral density (aBMD). PTH is a therapeutic option, yet data on the prolonged clinical and skeletal effects of PTH treatment are limited. We tracked annual daily doses of calcium and active vitamin D supplements, calciotropic biochemistries, estimated glomerular filtration rate (eGFR), and aBMD measurements in 27 HypoPT patients (16 postsurgical, 11 nonsurgical) who were treated with recombinant human PTH(1-84) [rhPTH(1-84)] for at least 8 (n = 27) and up to 12 (n = 14) years. We also performed high-resolution-peripheral quantitative computed tomography (HRpQCT) imaging and report results at baseline, 5, 8, and 12 years of rhPTH(1-84) treatment. With prolonged use of rhPTH, reductions in the need for supplemental calcium and active vitamin D were maintained. The eGFR did not decline. Serum calcium was maintained within the lower limit of the normal range. aBMD by dual-energy X-ray absorptiometry (DXA) showed an increase at the lumbar spine and a decrease at the distal 1/3 radius. By HRpQCT, cortical volumetric BMD (vBMD) at the tibia decreased at year 5: -20.0% ± 1.5%. The magnitude of this reduction was mitigated in year 8: -8.5% ± 1.6% and in year 12: -10.3% ± 2.2% but all were significantly below the mean baseline value (p < 0.001). A similar pattern of decline was observed at the radius. Cortical porosity progressively increased at the tibia in year 5: 17.4% ± 10% (p < 0.05), year 8: 55.2% ± 11% (p < 0.001), and year 12: 83.5% ± 14% (p < 0.001). A similar pattern of increase was observed at the radius. Failure load, which was higher than normal at baseline, decreased but remained above normal at year 12. This is the longest experience, to date, with PTH therapy in HypoPT. These results demonstrate sustained biochemical stability but overall decreases in bone mass. © 2023 American Society for Bone and Mineral Research (ASBMR).

Diabetes Risk Factors and Bone Microarchitecture as Assessed by High-Resolution Peripheral Quantitative Computed Tomography in Adults With Long-Standing Type 1 Diabetes.

OBJECTIVE: To determine whether type 1 diabetes and its complications are associated with bone geometry and microarchitecture. RESEARCH DESIGN AND METHODS: This cross-sectional study was embedded in a long-term observational study. High-resolution peripheral quantitative computed tomography (HR-pQCT) scans of the distal radius and distal and diaphyseal tibia were performed in a subset of 183 participants with type 1 diabetes from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study and 94 control participants without diabetes. HbA1c, skin advanced glycation end products (AGEs), and diabetes-related complications were assessed in EDIC participants with >30 years of follow-up. RESULTS: Compared with control participants (aged 60 ± 8 years, 65% female), EDIC participants (aged 60 ± 7 years, diabetes duration 38 ± 5 years, 51% female) had lower total bone mineral density (BMD) at the distal radius (-7.9% [95% CI -15.2%, -0.6%]; P = 0.030) and distal tibia (-11.3% [95% CI -18.5%, -4.2%]; P = 0.001); larger total area at all sites (distal radius 4.7% [95% CI 0.5%, 8.8%; P = 0.030]; distal tibia 5.9% [95% CI 2.1%, 9.8%; P = 0.003]; diaphyseal tibia 3.4% [95% CI 0.8%, 6.1%; P = 0.011]); and poorer radius trabecular and cortical microarchitecture. Estimated failure load was similar between the two groups. Among EDIC participants, higher HbA1c, AGE levels, and macroalbuminuria were associated with lower total BMD. Macroalbuminuria was associated with larger total area and lower cortical thickness at the distal radius. Higher HbA1c and AGE levels and lower glomerular filtration rate, peripheral neuropathy, and retinopathy were associated with deficits in trabecular microarchitecture. CONCLUSIONS: Type 1 diabetes is associated with lower BMD, larger bone area, and poorer trabecular microarchitecture. Among participants with type 1 diabetes, suboptimal glycemic control, AGE accumulation, and microvascular complications are associated with deficits in bone microarchitecture and lower BMD.

Efficacy and Safety of Parathyroid Hormone Replacement With TransCon PTH in Hypoparathyroidism: 26-Week Results From the Phase 3 PaTHway Trial.

Conventional therapy for hypoparathyroidism consisting of active vitamin D and calcium aims to alleviate hypocalcemia but fails to restore normal parathyroid hormone (PTH) physiology. PTH replacement therapy is the ideal physiologic treatment for hypoparathyroidism. The double-blind, placebo-controlled, 26-week, phase 3 PaTHway trial assessed the efficacy and safety of PTH replacement therapy for hypoparathyroidism individuals with the investigational drug TransCon PTH (palopegteriparatide). Participants (n = 84) were randomized 3:1 to once-daily TransCon PTH (initially 18 µg/d) or placebo, both co-administered with conventional therapy. The study drug and conventional therapy were titrated according to a dosing algorithm guided by serum calcium. The composite primary efficacy endpoint was the proportion of participants at week 26 who achieved normal albumin-adjusted serum calcium levels (8.3-10.6 mg/dL), independence from conventional therapy (requiring no active vitamin D and ≤600 mg/d of calcium), and no increase in study drug over 4 weeks before week 26. Other outcomes of interest included health-related quality of life measured by the 36-Item Short Form Survey (SF-36), hypoparathyroidism-related symptoms, functioning, and well-being measured by the Hypoparathyroidism Patient Experience Scale (HPES), and urinary calcium excretion. At week 26, 79% (48/61) of participants treated with TransCon PTH versus 5% (1/21) wiplacebo met the composite primary efficacy endpoint (p < 0.0001). TransCon PTH treatment demonstrated a significant improvement in all key secondary endpoint HPES domain scores (all p < 0.01) and the SF-36 Physical Functioning subscale score (p = 0.0347) compared with placebo. Additionally, 93% (57/61) of participants treated with TransCon PTH achieved independence from conventional therapy. TransCon PTH treatment normalized mean 24-hour urine calcium. Overall, 82% (50/61) treated with TransCon PTH and 100% (21/21) wiplacebo experienced adverse events; most were mild (46%) or moderate (46%). No study drug-related withdrawals occurred. In conclusion, TransCon PTH maintained normocalcemia while permitting independence from conventional therapy and was well-tolerated in individuals with hypoparathyroidism. © 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).

A Pilot Study of Cognition Among Hypoparathyroid Adults.

PURPOSE: Hypoparathyroid patients describe cognitive deficits, yet data regarding objective assessment of cognitive function are limited. We assessed cognition in a pilot study of hypoparathyroid patients using the National Institutes of Health Toolbox® Adult Cognitive Battery (NIHTB-CB). We also sought to determine whether cognition relates to emotion, quality of life, and hypoparathyroidism-related biochemistries. METHODS: Nineteen hypoparathyroid patients were studied. Objective cognition was assessed with NIHTB-CB. Impairment was defined as fully demographically adjusted T-score < 1.5 SD in at least 1 cognitive domain or < 1 SD in 2 or more domains. RESULTS: Of the 19 participants (17 women; median age 49; 18 postsurgical), impaired demographically adjusted NIHTB-CB cognition scores were observed in 13 subjects (68%). Cognition scores correlated with self-reported perception of general health. Processing speed was the most commonly impaired cognitive domain, with T-scores that were ≤2 SD in 6 subjects (32%). Processing speed correlated with serum calcium (r = 0.53, P = 0.023) and inversely with serum phosphate (r = -0.48, P = 0.042) levels. CONCLUSIONS: Impaired cognition using the NIHTB-CB was common in this small pilot cohort of hypoparathyroid patients. Slower processing speed was present and associated with lower serum calcium and higher serum phosphate levels. Larger controlled studies with additional neuropsychological testing are needed to investigate cognitive function in hypoparathyroidism.

Biochemical Markers of Bone Turnover in Older Adults With Type 1 Diabetes.

CONTEXT: Type 1 diabetes (T1D) is characterized by high fracture risk, yet little is known regarding diabetes-related mechanisms or risk factors. OBJECTIVE: Determine whether glycemic control, advanced glycation end products (AGEs), and microvascular complications are associated with bone turnover markers among older T1D adults. DESIGN: Cross-sectional. SETTING: Epidemiology of Diabetes Interventions and Complications study (6 of 27 clinical centers). PARTICIPANTS: 232 T1D participants followed for >30 years. EXPOSURES: Glycemic control ascertained as concurrent and cumulative hemoglobin A1c (HbA1c); kidney function, by estimated glomerular filtration rates (eGFR); and AGEs, by skin intrinsic fluorescence. MAIN OUTCOME MEASURES: Serum procollagen 1 intact N-terminal propeptide (PINP), bone-specific alkaline phosphatase (bone ALP), serum C-telopeptide (sCTX), tartrate-resistant acid phosphatase 5b (TRACP5b), and sclerostin. RESULTS: Mean age was 59.6 ±â€…6.8 years, and 48% were female. In models with HbA1c, eGFR, and AGEs, adjusted for age and sex, higher concurrent HbA1c was associated with lower PINP [ß -3.4 pg/mL (95% CI -6.1, -0.7), P = 0.015 for each 1% higher HbA1c]. Lower eGFR was associated with higher PINP [6.9 pg/mL (95% CI 3.8, 10.0), P < 0.0001 for each -20 mL/min/1.73 m2 eGFR], bone ALP [1.0 U/L (95% CI 0.2, 1.9), P = 0.011], sCTX [53.6 pg/mL (95% CI 32.6, 74.6), P < 0.0001], and TRACP5b [0.3 U/L (95% CI 0.1, 0.4), P = 0.002]. However, AGEs were not associated with any bone turnover markers in adjusted models. HbA1c, eGFR, and AGEs were not associated with sclerostin levels. CONCLUSIONS: Among older adults with T1D, poor glycemic control is a risk factor for reduced bone formation, while reduced kidney function is a risk factor for increased bone resorption and formation.

Risk factors for lower bone mineral density in older adults with type 1 diabetes: a cross-sectional study.

BACKGROUND: Type 1 diabetes is associated with lower bone mineral density (BMD) and increased fracture risk, but little is known regarding the effects of diabetes-related factors on BMD. We assessed whether these factors are associated with lower hip BMD among older adults with type 1 diabetes. METHODS: This cross-sectional study was embedded in a long-term observational study, the Epidemiology of Diabetes Interventions and Complications study (EDIC), a cohort of participants with type 1 diabetes, who were originally enrolled in the Diabetes Control and Complications Trial (DCCT), and were followed-up for more than 30 years at 27 sites in the USA and Canada. All active EDIC participants were eligible except if they were pregnant, weighed above the dual-energy x-ray absorptiometry (DXA) scanner limit, had an implanted neurostimulator, or were not willing to participate. The primary study outcome was total hip BMD. Hip, spine, and radius BMD and trabecular bone score (TBS) were measured with DXA at an annual EDIC visit (2017-19). Time-weighted mean HbA1c, kidney disease, and peripheral neuropathy were measured annually during EDIC, and retinopathy was measured every 4 years. Skin intrinsic fluorescence, a measure of advanced glycation end products (AGEs), and cardiac autonomic neuropathy were assessed once (2009-10) during EDIC. FINDINGS: 1147 of the 1441 participants who were enrolled in the DCCT trial remained active EDIC participants at the start of this cross-sectional study. Between Sept 20, 2017, and Sept 19, 2019, 1094 of 1147 participants were screened for the EDIC Skeletal Health study. 1058 participants completed at least one of a set of DXA scans and were included in the analysis. 47·8% were women and 52·2% were men, 96·6% were White and 3·4% were of other race or ethnicity. The mean age of participants was 59·2 years (SD 6·7). Higher mean HbA1c, higher skin intrinsic fluorescence, and kidney disease (but not retinopathy or neuropathy) were independently associated with a lower total hip BMD. Total hip BMD differed by -10·7 mg/cm2 (95% CI -19·6 to -1·7) for each 1% increase in mean HbA1c, -20·5 mg/cm2 (-29·9 to -11·0) for each 5 unit higher skin intrinsic fluorescence, and -51·7 mg/cm2 (-80·6 to -22·7) in the presence of kidney disease. Similar associations were found for femoral neck and ultra-distal radius BMD, but not for lumbar spine BMD or TBS. INTERPRETATION: Poorer glycaemic control, AGE accumulation, and kidney disease are independent risk factors for lower hip BMD in older adults with type 1 diabetes. Maintenance of glycaemic control and prevention of kidney disease might reduce bone loss and ultimately fractures in this population. Osteoporosis screening might be particularly important in people with these risk factors. Further research to identify AGE blockers could benefit skeletal health. FUNDING: National Institute of Diabetes and Digestive and Kidney Disease.

PaTH Forward: A Randomized, Double-Blind, Placebo-Controlled Phase 2 Trial of TransCon PTH in Adult Hypoparathyroidism.

CONTEXT: Hypoparathyroidism is characterized by insufficient levels of parathyroid hormone (PTH). TransCon PTH is an investigational long-acting prodrug of PTH(1-34) for the treatment of hypoparathyroidism. OBJECTIVE: This work aimed to investigate the safety, tolerability, and efficacy of daily TransCon PTH in adults with hypoparathyroidism. METHODS: This phase 2, randomized, double-blind, placebo-controlled 4-week trial with open-label extension enrolled 59 individuals with hypoparathyroidism. Interventions included TransCon PTH 15, 18, or 21 µg PTH(1-34)/day or placebo for 4 weeks, followed by a 22-week extension during which TransCon PTH dose was titrated (6-60 µg PTH[1-34]/day). RESULTS: By Week 26, 91% of participants treated with TransCon PTH achieved independence from standard of care (SoC, defined as active vitamin D = 0 µg/day and calcium [Ca] ≤ 500 mg/day). Mean 24-hour urine Ca (uCa) decreased from a baseline mean of 415 mg/24h to 178 mg/24h by Week 26 (n = 44) while normal serum Ca (sCa) was maintained and serum phosphate and serum calcium-phosphate product fell within the normal range. By Week 26, mean scores on the generic 36-Item Short Form Health Survey domains increased from below normal at baseline to within the normal range. The Hypoparathyroidism Patient Experience Scale symptom and impact scores improved through 26 weeks. TransCon PTH was well tolerated with no treatment-related serious or severe adverse events. CONCLUSION: TransCon PTH enabled independence from oral active vitamin D and reduced Ca supplements (≤ 500 mg/day) for most participants, achieving normal sCa, serum phosphate, uCa, serum calcium-phosphate product, and demonstrating improved health-related quality of life. These results support TransCon PTH as a potential hormone replacement therapy for adults with hypoparathyroidism.