Making the Cut: Parathyroidectomy Before or After Kidney Transplantation?

Timing of parathyroidectomy after kidney transplantation: A cost-effectiveness analysis

INTRODUCTION

Parathyroidectomy is the definitive treatment for tertiary hyperparathyroidism post-kidney transplantation. However, cinacalcet-based medical management is increasingly used as an alternative. The financial consequences of each treatment remain unclear. We aimed to identify the most cost-effective strategy for managing hyperparathyroidism from the kidney transplantation recipient's perspective.

METHODS

We constructed a patient-level discrete event simulation model to compare parathyroidectomy and cinacalcet-based medical management. The effects of hyperparathyroidism on allograft survival and all-cause mortality were considered in the discrete event simulation model with a time horizon of 15 years. Our base case was a 55-year-old kidney transplantation recipient with persistent hyperparathyroidism and hypercalcemia. The primary outcome was the cost-effectiveness measured by cost per quality-adjusted life years.

RESULTS

The monthly out-of-pocket cost of cinacalcet ranged from $12 to $288, depending on insurance coverage, with a base case cost of $150. Our base case analysis showed that parathyroidectomy was the dominant treatment with lesser cost ($1,315 vs $7,147) and greater effectiveness (3.17 quality-adjusted life years and 2.92 quality-adjusted life years) than cinacalcet. One-way sensitivity analysis on the cinacalcet treatment duration showed that parathyroidectomy became more cost-effective at 9 months. Two-way sensitivity analysis on the cost of cinacalcet and the duration of treatment with cinacalcet showed that as the monthly cost of cinacalcet increases, the expense of cinacalcet-based medical management quickly exceeds the cost of parathyroidectomy.

CONCLUSION

Parathyroidectomy becomes more cost-effective for kidney transplantation recipients with tertiary hyperparathyroidism when they require cinacalcet-based medical management for more than 9 months. As part of shared decision-making, it is important to discuss the financial costs involved in treating tertiary hyperparathyroidism.

Variable practice patterns in the surgical management of renal hyperparathyroidism

BACKGROUND

Hyperparathyroidism is common among patients with chronic kidney disease, end-stage kidney disease, and kidney transplant. The American Association for Endocrine Surgery published clinical practice guidelines that address the surgical treatment of secondary and tertiary hyperparathyroidism. The purpose of this study is to determine practice patterns for the surgical management of secondary and tertiary hyperparathyroidism prior to guideline publication.

METHODS

With the approval of the American Association for Endocrine Surgery, a Qualtrics email survey was sent to the Association's membership in 2022 about current clinical decision making for surgical treatment of secondary and tertiary hyperparathyroidism. Respondents were divided into groups based on surgical subspecialty (endocrine surgery versus non-endocrine surgery), yearly parathyroidectomy volume, and yearly parathyroidectomy volume for surgical treatment of secondary and tertiary hyperparathyroidism. Descriptive statistics were performed; the role of volume was evaluated.

RESULTS

There were 142 responses from 795 solicited email addresses (18% response rate); 114 (84%) identified as endocrine surgeons. The majority (62%) perform >50 parathyroidectomies yearly, but most perform <10 parathyroidectomies for surgical treatment of secondary and tertiary hyperparathyroidism per year (<10/y, 53.7%; 10-30/y, 41.9%; >30/y, 4.4%). Subtotal parathyroidectomy is most commonly performed for surgical treatment of secondary (83%) and tertiary (52%) hyperparathyroidism, but transcervical thymectomy variably performed for both. There was no consensus regarding starting calcitriol preoperatively (always 43%, never 25%, depends on vitamin D levels 24%) or stopping cinacalcet (2 weeks prior 28%, day of surgery 29%, postoperatively 20%). Surgeons who perform >10 parathyroidectomies per year for surgical treatment of secondary and tertiary hyperparathyroidism were less likely to consider the patient's preoperative vitamin D levels to inform their decision to start calcitriol before surgery (<10 cases/year, 34%; ≥10 cases/year 15%; P = .023), were more likely to have a postoperative hypocalcemia protocol managed by the surgical team (<10 cases/year, 49%; ≥10 cases/year, 58%; P = .029), and were more likely to use intraoperative parathyroid hormone monitoring for tertiary hyperparathyroidism (<10 cases/year, 70%; ≥10 cases/year, 87%; P = .046).

CONCLUSION

The majority of respondents perform <10 parathyroidectomies yearly for surgical treatment of secondary and tertiary hyperparathyroidism. Subtotal parathyroidectomy was most commonly performed, but there was little other consensus regarding preoperative management, intraoperative decision-making, and postoperative care. Opportunity exists through guideline dissemination to improve heterogeneity of care provided to surgical treatment of secondary and tertiary hyperparathyroidism patients.

Feasibility of an Online Patient-Driven International Parathyroid Registry

INTRODUCTION

Traditional parathyroid registries are labor-intensive and do not always capture long-term follow-up data. This study aimed to develop a patient-driven international parathyroid registry and leverage community connections to improve patient-centered care for hyperparathyroidism.

METHODS

An anonymous voluntary online survey was developed using Qualtrics and posted in an international patient and advocate-run social media group affiliated with over 11,700 members. The survey was developed from a literature review, expert opinion, and discussion with the social media group managers. It consists of seven sections: patient demographics, past medical history, preoperative symptoms, laboratory evaluation, preoperative imaging studies, operative findings, and operative outcomes.

RESULTS

From July 30, 2022, to October 1, 2022, 89 complete responses were received. Participants were from 12 countries, mostly (82.0%) from the United States across 31 states. Most participants were female (91.4%), White (96.7%) with a mean (±standard deviation) age of 58 ± 12 y. The most common preoperative symptoms were bone or joint pain (84.3%) and neuropsychiatric symptoms: including fatigue (82.0%), brain fog (79.8%), memory loss (79.8%), and difficulty with concentration (75.3%). The median (interquartile range) length from symptom onset to diagnosis was 40.0 (6.8-100.5) mo. Seventy-one percent of participants had elevated preoperative serum calcium, and 73.2% had elevated preoperative parathyroid hormone. All participants obtained preoperative imaging studies (88.4% ultrasound, 86.0% sestabimi scan, and 45.3% computed tomography). Among them, 48.8% of participants received two, and 34.9% had three imaging studies. The median (interquartile range) time from diagnosis to surgical intervention was 3 (2-9) mo. Twenty-two percent of participants traveled to different cities for surgical intervention. Forty-seven percent of participants underwent outpatient parathyroidectomy. Eighty-four percent of participants reported improved symptoms after parathyroidectomy, 12.4% required oral calcium supplementation for more than 6 mo, 32.6% experienced transient hoarseness after parathyroidectomy, and 14.6% required reoperation after initial parathyroidectomy.

CONCLUSIONS

This international online parathyroid registry provides a valuable collection of patient-entered clinical outcomes. The high number of responses over 10 wk demonstrates that participants were willing to be involved in research on their disease. The creation of this registry allows global participation and is feasible for future studies in hyperparathyroidism.

Resolution of Secondary Hyperparathyroidism After Kidney Transplantation and the Effect on Graft Survival

OBJECTIVE

Hyperparathyroidism (HPT) is nearly universal in patients with end-stage kidney disease. Kidney transplantation (KT) reverses HPT in many patients, but most studies have only focused on following calcium and not parathyroid hormone (PTH) levels. We sought to study the prevalence of persistent HPT post-KT at our center and its effect on graft survival.

METHODS

Patients who underwent KT from January 2015 to August 2021 were included and characterized by post-KT HPT status at the most recent follow-up: resolved (achieving normal PTH post-KT) versus persistent HPT. Those with persistent HPT were further stratified by the occurrence of hypercalcemia (normocalcemic versus hypercalcemic HPT). Patient demographics, donor kidney quality, PTH and calcium levels, and allograft function were compared between groups. Multivariable logistic regression and Cox regression with propensity score matching were conducted.

RESULTS

Of 1554 patients, only 390 (25.1%) patients had resolution of renal HPT post-KT with a mean (±SD) follow-up length of 40±23 months. The median (IQR) length of HPT resolution was 5 (0-16) months. Of the remaining 1164 patients with persistent HPT post-KT, 806 (69.2%) patients had high PTH and normal calcium levels, while 358 (30.8%) patients had high calcium and high PTH levels. Patients with persistent HPT had higher parathyroid hormone (PTH) at the time of KT [403 (243-659) versus 277 (163-454) pg/mL, P <0.001] and were more likely to have received cinacalcet treatment before KT (34.9% vs. 12.3%, P <0.001). Only 6.3% of patients with persistent HPT received parathyroidectomy. Multivariable logistic regression showed race, cinacalcet use pre-KT, dialysis before KT, receiving an organ from a deceased donor, high PTH, and calcium levels at KT were associated with persistent HPT post-KT. After adjusting for patient demographics and donor kidney quality by propensity score matching, persistent HPT (HR 2.5, 95% CI 1.1-5.7, P =0.033) was associated with a higher risk of allograft failure. Sub-analysis showed that both hypercalcemic HPT (HR 2.6, 95% CI 1.1-6.5, P =0.045) and normocalcemic HPT (HR 2.5, 95% CI 1.3-5.5, P =0.021) were associated with increased risk of allograft failure when compared with patients with resolved HPT.

CONCLUSION

Persistent HPT is common (75%) after KT and is associated with a higher risk of allograft failure. PTH levels should be closely monitored after kidney transplantation so that patients with persistent HPT can be treated appropriately.

Less Is More: Parathyroidectomy and Association with Postoperative Hypocalcemia in Dialysis Patients

BACKGROUND

Parathyroidectomy (PTx) is the most effective treatment for secondary hyperparathyroidism. Literature regarding the effect of surgical approaches on postoperative hypocalcemia is limited and mainly focuses on postoperative calcium levels. This study aims to evaluate the association of subtotal PTx and total PTx with autotransplantation for secondary hyperparathyroidism with postoperative hypocalcemia.

STUDY DESIGN

We reviewed all dialysis patients who underwent PTx (n = 143) at our institution from 2010 to 2021. Postoperative hypocalcemia adverse events were defined as postoperative intravenous calcium requirement or 30-day readmission due to hypocalcemia. Postoperative hypocalcemia adverse events, length of stay, and oral calcium requirement at 1-month follow-up were compared between the 2 groups.

RESULTS

Of the 143 patients, 119 (83.2%) underwent total PTx with autotransplantation, and 24 (16.8%) underwent subtotal PTx. Patients who underwent subtotal PTx had shorter mean ± SD length of stay (1.8 ± 1.7 vs 3.5 ± 3.2, p = 0.002), were less likely to develop hypocalcemia adverse events (8.3% vs 47.1%, p < 0.001), and required less median elemental calcium supplementation at 1-month follow-up (1,558 vs 3,193 mg, p < 0.001). There was no significant difference in surgical success between the 2 groups (91.7% vs 89.1%, p = 0.706). Stepwise multivariable regression demonstrated that patients who underwent total PTx with autotransplantation were 11.9 times more likely to develop hypocalcemia adverse events (adjusted odds ratio 11.9, 95% CI 2.2 to 66.2, p = 0.004), had 1.24 days longer length of stay (95% CI 0.04 to 2.44, p = 0.044), and required 1,776.1 mg more elemental calcium (95% CI 661.5 to 2,890.6 mg, p = 0.002).

CONCLUSIONS

Subtotal parathyroidectomy is associated with less postoperative hypocalcemia and provides similar surgical cure for dialysis patients with secondary hyperparathyroidism.