Evaluation of Adrenal Incidentaloma.

Adrenal incidentalomas have increased due to advanced and more sensitive imaging modalities, their increased utilization, and the aging population. Most adrenal incidentalomas are nonfunctional and benign, but a subset of patients has functional and/or malignant tumors. The evaluation of patients with an adrenal incidentaloma involves addressing 2 clinical questions: (1) Is the tumor functional? (2) Is the tumor malignant? A careful history and physical examination focused on signs and symptoms of adrenal functional tumors, biochemical testing, and imaging features are the cornerstone in the evaluation of patients with an adrenal incidentaloma.

Evidence of the Role of Inflammation and the Hormonal Environment in the Pathogenesis of Adrenal Myelolipomas in Congenital Adrenal Hyperplasia.

Adrenal myelolipomas (AML) are composed of mature adipose and hematopoietic components. They represent approximately 3 percent of adrenal tumors and are commonly found in patients with congenital adrenal hyperplasia (CAH). CAH provides a unique environment to explore AML pathogenesis. We aimed to evaluate the role of the immune system and hormones that accumulate in poorly controlled CAH in the development of AML. When compared to normal adrenal tissue, CAH-affected adrenal tissue and myelolipomas showed an increased expression of inflammatory cells (CD68, IL2Rbeta), stem cells (CD117) B cells (IRF4), and adipogenic markers (aP2/FABP4, AdipoQ, PPARγ, Leptin, CideA), and immunostaining showed nodular lymphocytic accumulation. Immunohistochemistry staining revealed a higher density of inflammatory cells (CD20, CD3, CD68) in CAH compared to non-CAH myelolipomas. In vitro RNA-sequencing studies using NCI-H295R adrenocortical cells with exogenous exposure to ACTH, testosterone, and 17-hydroxyprogesterone hormones, showed the differential expression of genes involved in cell cycle progression, phosphorylation, and tumorigenesis. Migration of B-lymphocytes was initiated after the hormonal treatment of adrenocortical cells using the Boyden chamber chemotaxis assay, indicating a possible hormonal influence on triggering inflammation and the development of myelolipomas. These findings demonstrate the important role of inflammation and the hormonal milieu in the development of AML in CAH.

Anaplastic thyroid cancer spheroids as preclinical models to test therapeutics.

Anaplastic thyroid cancer (ATC) is the most aggressive thyroid cancer. Despite advances in tissue culture techniques, a robust model for ATC spheroid culture is yet to be developed. In this study, we created an efficient and cost-effective 3D tumor spheroids culture system from human ATC cells and existing cell lines that better mimic patient tumors and that can enhance our understanding of in vivo treatment response. We found that patient-derived ATC cells and cell lines can readily form spheroids in culture with a unique morphology, size, and cytoskeletal organization. We observed both cohesive (dense and solid structures) and discohesive (irregularly shaped structures) spheroids within the same culture condition across different cell lines. BRAFWT ATC spheroids grew in a cohesive pattern, while BRAFV600E-mutant ATC spheroids had a discohesive organization. In the patient-derived BRAFV600E-mutant ATC spheroids, we observed both growth patterns, but mostly the discohesive type. Histologically, ATC spheroids had a similar morphology to the patient's tumor through H&E staining and proliferation marker staining. Moreover, RNA sequencing analysis revealed that the gene expression profile of tumor cells derived from the spheroids closely matched parental patient tumor-derived cells in comparison to monolayer cultures. In addition, treatment response to combined BRAF and MEK inhibition in BRAFV600E-mutant ATC spheroids exhibited a similar sensitivity to the patient clinical response. Our study provides a robust and novel ex vivo spheroid model system that can be used in both established ATC cell lines and patient-derived tumor samples to better understand the biology of ATC and to test therapeutics.

Disparities in access to high-volume parathyroid surgeons in the United States: A call to action.

BACKGROUND: Parathyroidectomy by a high-volume surgeon is associated with a reduced risk of perioperative complications and of failure to cure primary and secondary hyperparathyroidism. There are limited data on disparities in access to high-volume parathyroid surgeons in the United States. METHODS: We used publicly available 2019 Medicare Provider Utilization and Payment data to identify all surgeons who performed >10 parathyroidectomies for Medicare fee-for-service beneficiaries, anticipating that fee-for-service beneficiaries likely represent only a subset of their high-volume practices. High-volume parathyroid surgeon characteristics and geographic distribution were evaluated. Inequality in the distribution of surgeons was measured by the Gini coefficient. The association between neighborhood disadvantage, based on the Area Deprivation Index, and proximity to high-volume parathyroid surgeons was evaluated using a one-way analysis of variance with Bonferroni-corrected pairwise comparisons. A sensitivity analysis was performed restricting to high-volume parathyroid surgeons within each hospital referral region, evidence-based regional markets for tertiary medical care. RESULTS: We identified 445 high-volume parathyroid surgeons who met inclusion criteria with >10 parathyroidectomies for Medicare fee-for-service beneficiaries. High-volume parathyroid surgeons were 71% male sex, and 59.8% were general surgeons. High-volume parathyroid surgeons were more likely to practice in a Metropolitan Statistical Area with a population >1 million than in less populous metropolitan or rural areas. The number of high-volume parathyroid surgeons per 100,000 fee-for-service Medicare beneficiaries in the 53 most populous Metropolitan Statistical Areas ranged from 0 to 4.94, with the highest density identified in Salt Lake City, Utah. In 2019, 50% of parathyroidectomies performed by high-volume parathyroid surgeons were performed by 20% of surgeons in this group, suggesting unequal distribution of surgical care (Gini coefficient 0.41). Patients in disadvantaged neighborhoods were farther from high-volume parathyroid surgeons than those in advantaged neighborhoods (median distance: disadvantaged 27.8 miles, partially disadvantaged 20.7 miles, partially advantaged 12.1 miles, advantaged 8.4 miles; P < .001). This association was also shown in the analysis of distance to high-volume parathyroid surgeons within the hospital referral region (P < .001). CONCLUSION: Older adults living in disadvantaged neighborhoods have less access to high-volume parathyroid surgeons, which may adversely affect treatment and outcomes for patients with primary and secondary hyperparathyroidism. This disparity highlights the need for actionable strategies to provide equitable access to care, including improved regionalization of high-volume parathyroid surgeon services and easing travel-related burdens for underserved patients.

Advances in translational research of the rare cancer type adrenocortical carcinoma.

Adrenocortical carcinoma is a rare malignancy with an annual worldwide incidence of 1-2 cases per 1 million and a 5-year survival rate of <60%. Although adrenocortical carcinoma is rare, such rare cancers account for approximately one third of patients diagnosed with cancer annually. In the past decade, there have been considerable advances in understanding the molecular basis of adrenocortical carcinoma. The genetic events associated with adrenocortical carcinoma in adults are distinct from those of paediatric cases, which are often associated with germline or somatic TP53 mutations and have a better prognosis. In adult primary adrenocortical carcinoma, the main somatic genetic alterations occur in genes that encode proteins involved in the WNT-ß-catenin pathway, cell cycle and p53 apoptosis pathway, chromatin remodelling and telomere maintenance pathway, cAMP-protein kinase A (PKA) pathway or DNA transcription and RNA translation pathways. Recently, integrated molecular studies of adrenocortical carcinomas, which have characterized somatic mutations and the methylome as well as gene and microRNA expression profiles, have led to a molecular classification of these tumours that can predict prognosis and have helped to identify new therapeutic targets. In this Review, we summarize these recent translational research advances in adrenocortical carcinoma, which it is hoped could lead to improved patient diagnosis, treatment and outcome.

Combination BRAFV600E Inhibition with the Multitargeting Tyrosine Kinase Inhibitor Axitinib Shows Additive Anticancer Activity in BRAFV600E-Mutant Anaplastic Thyroid Cancer.

Background: Anaplastic thyroid cancer (ATC) is uniformly lethal. BRAFV600E mutation is present in 45% of patients with ATC. Targeted therapy with combined BRAF and MEK inhibition in BRAFV600E-mutant ATC can be effective, but acquired resistance is common because this combination targets the same pathway. Drug matrix screening, in BRAFV600E ATC cells, of highly active compounds in combination with BRAF inhibition showed multitargeting tyrosine kinase inhibitors (MTKIs) had the highest synergistic/additive activity. Thus, we hypothesized that the combination of BRAFV600E inhibition and an MTKI is more effective than a single drug or combined BRAF and MEK inhibition in BRAFV600E-mutant ATC. We evaluated the effect of BRAFV600E inhibitors in combination with the MTKI axitinib and its mechanism(s) of action. Methods: We evaluated the effects of BRAFV600E inhibitors and axitinib alone and in combination in in vitro and in vivo models of BRAFV600E-mutant and wild-type ATC. Results: The combination of axitinib and BRAFV600E inhibitors (dabrafenib and PLX4720) showed an additive effect on inhibiting cell proliferation based on the Chou-Talalay algorithm in BRAFV600E-mutant ATC cell lines. This combination also significantly inhibited cell invasion and migration (p < 0.001) compared with the control. Dabrafenib and PLX4720 arrested ATC cells in the G0/G1 phase. Axitinib arrested ATC cells in the G2/M phase by decreasing phosphorylation of aurora kinase B (Thr232) and histone H3 (Ser10) proteins and by upregulating the c-JUN signaling pathway. The combination of BRAF inhibition and axitinib significantly inhibited tumor growth and was associated with improved survival in an orthotopic ATC model. Conclusions: The novel combination of axitinib and BRAFV600E inhibition enhanced anticancer activity in in vitro and in vivo models of BRAFV600E-mutant ATC. This combination may have clinical utility in BRAFV600E-mutant ATC that is refractory to current standard therapy, namely combined BRAF and MEK inhibition.

Estimated Effect of Parathyroidectomy on Long-Term Kidney Function in Adults With Primary Hyperparathyroidism.

BACKGROUND: Multidisciplinary guidelines recommend parathyroidectomy to slow the progression of chronic kidney disease in patients with primary hyperparathyroidism (PHPT) and an estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2. Limited data address the effect of parathyroidectomy on long-term kidney function. OBJECTIVE: To compare the incidence of a sustained decline in eGFR of at least 50% among patients with PHPT treated with parathyroidectomy versus nonoperative management. DESIGN: Target trial emulation was done using observational data from adults with PHPT, using an extended Cox model with time-varying inverse probability weighting. SETTING: Veterans Health Administration. PATIENTS: Patients with a new biochemical diagnosis of PHPT in 2000 to 2019. MEASUREMENTS: Sustained decline of at least 50% from pretreatment eGFR. RESULTS: Among 43 697 patients with PHPT (mean age, 66.8 years), 2928 (6.7%) had a decline of at least 50% in eGFR over a median follow-up of 4.9 years. The weighted cumulative incidence of eGFR decline was 5.1% at 5 years and 10.8% at 10 years in patients managed with parathyroidectomy, compared with 5.1% and 12.0%, respectively, in those managed nonoperatively. The adjusted hazard of eGFR decline did not differ between parathyroidectomy and nonoperative management (hazard ratio [HR], 0.98 [95% CI, 0.82 to 1.16]). Subgroup analyses found no heterogeneity of treatment effect based on pretreatment kidney function. Parathyroidectomy was associated with a reduced hazard of the primary outcome among patients younger than 60 years (HR, 0.75 [CI, 0.59 to 0.93]) that was not evident among those aged 60 years or older (HR, 1.08 [CI, 0.87 to 1.34]). LIMITATION: Analyses were done in a predominantly male cohort using observational data. CONCLUSION: Parathyroidectomy had no effect on long-term kidney function in older adults with PHPT. Potential benefits related to kidney function should not be the primary consideration for PHPT treatment decisions. PRIMARY FUNDING SOURCE: National Institute on Aging.

Increased Risk of Complications Associated With Concurrent Parathyroidectomy in Patients Undergoing Total Thyroidectomy.

INTRODUCTION: We sought to investigate the association of concurrent parathyroidectomy (PTX) with risks of total thyroidectomy (TTX) through analysis of Collaborative Endocrine Surgery Quality Improvement Program data. TTXis a common operation with complications including recurrent laryngeal nerve injury, neck hematoma, and hypoparathyroidism. A subset of patients undergoing thyroidectomy undergoes planned concurrent PTX for treatment of primary hyperparathyroidism. There are limited data on the risk profile of TTX with concurrent PTX (TTX + PTX). METHODS: We queried the Collaborative Endocrine Surgery Quality Improvement Program database for patients who underwent TTX or TTX + PTX from January 2014 through April 2020. Multivariable logistic regression was performed to predict hypoparathyroidism, vocal cord dysfunction, neck hematoma, and postoperative emergency department visit. Covariates included patient demographics, patient body mass index, indication for surgery, central neck dissection, anticoagulation use, and surgeon volume. RESULTS: Thirteen thousand six hundred forty seven patients underwent TTX and 654 patients underwent TTX + PTX. Unadjusted rates of hypoparathyroidism were higher in TTX + PTX patients at 30 d (9.6% versus 7.4%, P = 0.04) and 6 mo (7.9% versus 3.1%, P < 0.001). On multivariable regression, TTX + PTX was associated with an increased risk of hypoparathyroidism at 30 d (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.57-2.79) and 6 mo (OR 4.63, 95% CI 3.06-7.00) and an increased risk of postoperative emergency department visit (OR 1.66, 95% CI 1.20-2.31). TTX + PTX was not associated with recurrent laryngeal nerve injury or neck hematoma. CONCLUSIONS: Concurrent PTX in patients undergoing TTX is associated with increased risk of immediate and long-term hypoparathyroidism, which should be considered in informed consent discussions and operative decision-making.

A Contemporary Review of the Treatment of Medullary Thyroid Carcinoma in the Era of New Drug Therapies.

Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor that can be sporadic or inherited and is often associated with mutations in the RET (Rearranged during Transfection) oncogene. The primary treatment for MTC is surgical resection of all suspected disease, but recent advances in targeted therapies for MTC, including the selective RET inhibitors selpercatinib and pralsetinib, have led to changes in the management of patients with locally advanced, metastatic, or recurrent MTC. In this article, we review updates on the evaluation and management of patients with MTC, focusing on new and emerging therapies that are likely to improve patient outcomes.

A multicenter evaluation of near-infrared autofluorescence imaging of parathyroid glands in thyroid and parathyroid surgery.

BACKGROUND: The usefulness of incorporating near-infrared autofluorescence into the surgical workflow of endocrine surgeons is unclear. Our aim was to develop a prospective registry and gather expert opinion on appropriate use of this technology. METHODS: This was a prospective multicenter collaborative study of patients undergoing thyroidectomy and parathyroidectomy at 7 academic centers. A questionnaire was disseminated among 24 participating surgeons. RESULTS: Overall, 827 thyroidectomy and parathyroidectomy procedures were entered into registry: 42% of surgeons found near-infrared autofluorescence useful in identifying parathyroid glands before they became apparent; 67% correlated near-infrared autofluorescence pattern to normal and abnormal glands; 38% of surgeons used near-infrared autofluorescence, rather than frozen section, to confirm parathyroid tissue; and 87% and 78% of surgeons reported near-infrared autofluorescence did not improve the success rate after parathyroidectomy or the ability to find ectopic glands, respectively. During thyroidectomy, 66% of surgeons routinely used near-infrared autofluorescence to rule out inadvertent parathyroidectomy. However, only 36% and 45% felt near-infrared autofluorescence decreased inadvertent parathyroidectomy rates and improved ability to preserve parathyroid glands during central neck dissections, respectively. CONCLUSION: This survey study identified areas of greatest potential use for near-infrared autofluorescence, which can form the basis of future objective trials to document the usefulness of this technology.

Risk of Permanent Hypoparathyroidism Requiring Calcitriol Therapy in a Population-Based Cohort of Adults Older Than 65 Undergoing Total Thyroidectomy for Graves' Disease.

Objective: Total thyroidectomy for Graves' disease (GD) is associated with rapid treatment of hyperthyroidism and low recurrence rates. However, it carries the risk of surgical complications including permanent hypoparathyroidism, which contributes to long-term impaired quality of life. The objective of this study was to determine the incidence of permanent hypoparathyroidism requiring calcitriol therapy among a population-based cohort of older adults undergoing total thyroidectomy for GD in the United States. Methods: We performed a population-based cohort study using 100% Medicare claims from beneficiaries older than 65 years with GD who underwent total thyroidectomy from 2007 to 2017. We required continuous enrollment in Medicare Parts A, B, and D for 12 months before and after surgery to ensure access to comprehensive claims data. Patients were excluded if they had a preoperative diagnosis of thyroid cancer or were on long-term preoperative calcitriol. Our primary outcome was permanent hypoparathyroidism, which was identified based on persistent use of calcitriol between 6 and 12 months following thyroidectomy. We used multivariable logistic regression to identify characteristics associated with permanent hypoparathyroidism, including patient age, sex, race/ethnicity, neighborhood disadvantage, Charlson-Deyo Comorbidity Index, urban or rural residence, and frailty. Results: We identified 4650 patients who underwent total thyroidectomy for GD during the study period and met the inclusion criteria (mean age = 72.8 years [standard deviation = 5.5], 86% female, and 79% white). Among this surgical cohort, 104 (2.2% [95% confidence interval, CI = 1.8-2.7%]) patients developed permanent hypoparathyroidism requiring calcitriol therapy. Patients who developed permanent hypoparathyroidism were on average older (mean age 74.1 vs. 72.8 years) than those who did not develop permanent hypoparathyroidism (p = 0.04). On multivariable regression, older age was the only patient characteristic associated with permanent hypoparathyroidism (odds ratio age ≥76 years = 1.68 [CI = 1.13-2.51] compared with age 66-75 years). Conclusions: The risk of permanent hypoparathyroidism requiring calcitriol therapy among this national, U.S. population-based cohort of older adults with GD treated with total thyroidectomy was low, even when considering operations performed by a heterogeneous group of surgeons. These findings suggest that the risk of hypoparathyroidism should not be a deterrent to operative management for GD in older adults who are appropriate surgical candidates.

Adverse Cardiovascular Outcomes Among Older Adults With Primary Hyperparathyroidism Treated With Parathyroidectomy Versus Nonoperative Management.

OBJECTIVE: The authors sought to compare the incidence of adverse cardiovascular (CV) events in older adults with primary hyperparathyroidism (PHPT) treated with parathyroidectomy versus nonoperative management. BACKGROUND: PHPT is a common endocrine disorder that is associated with increased CV mortality, but it is not known whether parathyroidectomy reduces the incidence of adverse CV events. METHODS: The authors conducted a population-based, longitudinal cohort study of Medicare beneficiaries diagnosed with PHPT (2006-2017). Multivariable, inverse probability weighted Cox proportional hazards regression was used to determine the associations of parathyroidectomy with major adverse cardiovascular events (MACEs), CV disease-related hospitalization, and CV hospitalization-associated mortality. RESULTS: The authors identified 210,206 beneficiaries diagnosed with PHPT from 2006 to 2017. Among 63,136 (30.0%) treated with parathyroidectomy and 147,070 (70.0%) managed nonoperatively within 1 year of diagnosis, the unadjusted incidence of MACE was 10.0% [mean follow-up 59.1 (SD 35.6) months] and 11.5% [mean follow-up 54.1 (SD 34.0) months], respectively. In multivariable analysis, parathyroidectomy was associated with a lower incidence of MACE [hazard ratio (HR): 0.92; 95% confidence interval (95% CI): 0.90-0.94], CV disease-related hospitalization (HR: 0.89; 95% CI: 0.87-0.91), and CV hospitalization-associated mortality (HR: 0.76; 95% CI: 0.71-0.81) compared to nonoperative management. At 10 years, parathyroidectomy was associated with adjusted absolute risk reduction for MACE of 1.7% (95% CI: 1.3%-2.1%), for CV disease-related hospitalization of 2.5% (95% CI: 2.1%-2.9%), and for CV hospitalization-associated mortality of 1.4% (95% CI: 1.2%-1.6%). CONCLUSIONS: In this large, population-based cohort study, parathyroidectomy was associated with a lower long-term incidence of adverse CV outcomes when compared with nonoperative management for older adults with PHPT, which is relevant to surgical decision making for patients with a long life expectancy.

Kidney Stone Events Following Parathyroidectomy vs Nonoperative Management for Primary Hyperparathyroidism.

CONTEXT: Primary hyperparathyroidism (PHPT) is associated with an increased risk of kidney stones. Few studies account for PHPT severity or stone risk when comparing stone events after parathyroidectomy vs nonoperative management. OBJECTIVE: Compare the incidence of kidney stone events in PHPT patients treated with parathyroidectomy vs nonoperative management. DESIGN: Longitudinal cohort study with propensity score inverse probability weighting and multivariable Cox proportional hazards regression. SETTING: Veterans Health Administration integrated health care system. PATIENTS: A total of 44 978 patients with > 2 years follow-up after PHPT diagnosis (2000-2018); 5244 patients (11.7%) were treated with parathyroidectomy. MAIN OUTCOMES MEASURE: Clinically significant kidney stone event. RESULTS: The cohort had a mean age of 66.0 years, was 87.8% male, and 66.4% White. Patients treated with parathyroidectomy had higher mean serum calcium (11.2 vs 10.8mg/dL) and were more likely to have a history of kidney stone events. Among patients with baseline history of kidney stones, the unadjusted incidence of ≥ 1 kidney stone event was 30.5% in patients managed with parathyroidectomy (mean follow-up, 5.6 years) compared with 18.0% in those managed nonoperatively (mean follow-up, 5.0 years). Patients treated with parathyroidectomy had a higher adjusted hazard of recurrent kidney stone events (hazard ratio [HR], 1.98; 95% CI, 1.56-2.51); however, this association declined over time (parathyroidectomy × time: HR, 0.80; 95% CI, 0.73-0.87). CONCLUSION: In this predominantly male cohort with PHPT, patients treated with parathyroidectomy continued to be at higher risk of kidney stone events in the immediate years after treatment than patients managed nonoperatively, although the adjusted risk of stone events declined with time, suggesting a benefit to surgical treatment.

SDHB knockout and succinate accumulation are insufficient for tumorigenesis but dual SDHB/NF1 loss yields SDHx-like pheochromocytomas.

Inherited pathogenic succinate dehydrogenase (SDHx) gene mutations cause the hereditary pheochromocytoma and paraganglioma tumor syndrome. Syndromic tumors exhibit elevated succinate, an oncometabolite that is proposed to drive tumorigenesis via DNA and histone hypermethylation, mitochondrial expansion, and pseudohypoxia-related gene expression. To interrogate this prevailing model, we disrupt mouse adrenal medulla SDHB expression, which recapitulates several key molecular features of human SDHx tumors, including succinate accumulation but not 5hmC loss, HIF accumulation, or tumorigenesis. By contrast, concomitant SDHB and the neurofibromin 1 tumor suppressor disruption yields SDHx-like pheochromocytomas. Unexpectedly, in vivo depletion of the 2-oxoglutarate (2-OG) dioxygenase cofactor ascorbate reduces SDHB-deficient cell survival, indicating that SDHx loss may be better tolerated by tissues with high antioxidant capacity. Contrary to the prevailing oncometabolite model, succinate accumulation and 2-OG-dependent dioxygenase inhibition are insufficient for mouse pheochromocytoma tumorigenesis, which requires additional growth-regulatory pathway activation.

Risk of Fracture Among Older Adults With Primary Hyperparathyroidism Receiving Parathyroidectomy vs Nonoperative Management.

Importance: Primary hyperparathyroidism (PHPT) contributes to the development and progression of osteoporosis in older adults. The effectiveness of parathyroidectomy for reducing fracture risk in older adults is unknown. Objective: To compare the incidence of clinical fracture among older adults with PHPT treated with parathyroidectomy vs nonoperative management. Design, Setting, and Participants: This was a population-based, longitudinal cohort study of all Medicare beneficiaries with PHPT from 2006 to 2017. Multivariable, inverse probability weighted Cox proportional hazards and Fine-Gray competing risk regression models were constructed to determine the association of parathyroidectomy vs nonoperative management with incident fracture. Data analysis was conducted from February 17, 2021, to September 14, 2021. Main Outcomes and Measures: The primary outcome was clinical fracture at any anatomic site not associated with major trauma during the follow-up period. Results: Among the 210 206 Medicare beneficiaries with PHPT (mean [SD] age, 75 [6.8] years; 165 637 [78.8%] women; 183 433 [87.3%] White individuals), 63 136 (30.0%) underwent parathyroidectomy within 1 year of diagnosis, and 147 070 (70.0%) were managed nonoperatively. During a mean (SD) follow-up period of 58.5 (35.5) months, the unadjusted incidence of fracture was 10.2% in patients treated with parathyroidectomy. During a mean (SD) follow-up of 52.5 (33.8) months, the unadjusted incidence of fracture was 13.7% in patients observed nonoperatively. On multivariable analysis, parathyroidectomy was associated with lower adjusted rates of any fracture (hazard ratio [HR], 0.78; 95% CI, 0.76-0.80]) and hip fracture (HR, 0.76; 95% CI, 0.72-0.79). At 2, 5, and 10 years, parathyroidectomy was associated with adjusted absolute fracture risk reduction of 1.2% (95% CI, 1.0-1.4), 2.8% (95% CI, 2.5-3.1), and 5.1% (95% CI, 4.6-5.5), respectively, compared with nonoperative management. On subgroup analysis, there were no significant differences in the association of parathyroidectomy with fracture risk by age group, sex, frailty, history of osteoporosis, or meeting operative guidelines. Fine-Gray competing risk regression confirmed parathyroidectomy was associated with a lower probability of any fracture and hip fracture when accounting for the competing risk of death (HR, 0.84; 95% CI, 0.82-0.85; and HR, 0.83; 95% CI, 0.80-0.85, respectively). Conclusions and Relevance: This longitudinal cohort study found that parathyroidectomy was associated with a lower risk of any fracture and hip fracture among older adults with PHPT, suggesting a clinically meaningful benefit of operative management in this population.

Racial disparities in the utilization of parathyroidectomy among patients with primary hyperparathyroidism: Evidence from a nationwide analysis of Medicare claims.

BACKGROUND: Among patients with primary hyperparathyroidism, parathyroidectomy offers a chance of cure and mitigation of disease-related complications. The impact of race/ethnicity on referral and utilization of parathyroidectomy has not been fully explored. METHODS: Population-based, retrospective cohort study using 100% Medicare claims from beneficiaries with primary hyperparathyroidism from 2006 to 2016. Associations of race/ethnicity with disease severity, surgeon evaluation, and subsequent parathyroidectomy were analyzed using adjusted multivariable logistic regression models. RESULTS: Among 210,206 beneficiaries with primary hyperparathyroidism, 63,136 (30.0%) underwent parathyroidectomy within 1 year of diagnosis. Black patients were more likely than other races/ethnicities to have stage 3 chronic kidney disease (10.8%) but had lower prevalence of osteoporosis and nephrolithiasis compared to White patients, Black and Hispanic patients were more likely to have been hospitalized for primary hyperparathyroidism-associated conditions (White 4.8%, Black 8.1%, Hispanic 5.8%; P < .001). Patients who were White and met operative criteria were more likely to undergo parathyroidectomy than Black, Hispanic, or Asian patients (White 30.5%, Black 23.0%, Hispanic 21.4%, Asian 18.7%; P < .001). Black and Hispanic patients had lower adjusted odds of being evaluated by a surgeon (odds ratios 0.71 [95% confidence interval 0.69-0.74], 0.68 [95% confidence interval 0.61-0.74], respectively) and undergoing parathyroidectomy if evaluated by a surgeon (odds ratios 0.72 [95% confidence interval 0.68-0.77], 0.82 [95% confidence interval 0.67-0.99]). Asian race was associated with lower adjusted odds of being evaluated by a surgeon (odds ratio 0.64 [95% confidence interval 0.57-0.71]), but no difference in odds of parathyroidectomy. CONCLUSION: Racial/ethnic disparities exist in the management of primary hyperparathyroidism among older adults. Determining the factors that account for this disparity require urgent attention to achieve parity in the management of primary hyperparathyroidism.