The rate, cost and outcomes of parathyroidectomy in the united states dialysis population from 2016-2018

Predictive Risk Score for Postparathyroidectomy Hungry Bone Syndrome in Patients With Secondary Hyperparathyroidism

PURPOSE

Secondary hyperparathyroidism (SHPT) frequently affects patients with end-stage renal disease. Hungry bone syndrome (HBS) is a common complication among patients who undergo parathyroidectomy for SHPT and may cause prolonged hospitalization or require intensive care. The objective of this study is to develop a scoring system to stratify patients according to their risk of developing HBS.

METHODS

A retrospective cohort study was performed using the US Renal Data System (2010-2021). Univariable and multivariable logistic regression models were developed and weighted β-coefficients from the multivariable model were used to construct a risk score for the development of HBS. Positive and negative predictive values were assessed.

RESULTS

Of 17 074 patients who underwent parathyroidectomy for SHPT, 19.4% developed HBS. Intensive care unit admission was more common in patients who developed HBS (33.5% vs 24.6%, P < .001). On multivariable logistic regression analysis, younger age, renal osteodystrophy, longer duration of dialysis, longer duration of kidney transplant, and higher Elixhauser score were significantly associated with HBS. A risk score based on these clinical factors was developed, with a total of 6 possible points. Rates of HBS ranged from 8% in patients with 0 points to 44% in patients with 6 points. The risk score had a poor positive predictive value (20.3%) but excellent negative predictive value (89.3%) for HBS.

CONCLUSION

We developed a weighted risk score that effectively stratifies patients by risk for developing HBS after parathyroidectomy. This tool can be used to counsel patients and to identify patients who may not require postoperative hospitalization.

Exploring kidney dialysis costs in the United States: a scoping review

AIMS

The increasing prevalence of end-stage renal disease (ESRD) in the United States (US) represents a considerable economic burden due to the high cost of dialysis treatment. This review examines data from real-world studies to identify cost drivers and explore areas where dialysis costs could be reduced.

METHODS

We identified and synthesized evidence published from 2016-2023 reporting direct dialysis costs in adult US patients from a comprehensive literature search of MEDLINE, Embase, and grey literature sources (e.g. US Renal Data System reports).

RESULTS

Most identified data related to Medicare expenditures. Overall Medicare spending in 2020 was $29B for hemodialysis and $2.8B for peritoneal dialysis (PD). Dialysis costs accounted for almost 80% of total Medicare expenditures on ESRD beneficiaries. Private insurance payers consistently pay more for dialysis; for example, per person per month spending by private insurers on outpatient dialysis was estimated at $10,149 compared with Medicare spending of $3,364. Dialysis costs were higher in specific high-risk patient groups (e.g. type 2 diabetes, hepatitis C). Spending on hemodialysis was higher than on PD, but the gap in spending between PD and hemodialysis is closing. Vascular access costs accounted for a substantial proportion of dialysis costs.

LIMITATIONS

Insufficient detail in the identified studies, especially related to outpatient costs, limits opportunities to identify key drivers. Differences between the studies in methods of measuring dialysis costs make generalization of these results difficult.

CONCLUSIONS

These findings indicate that prevention of or delay in progression to ESRD could have considerable cost savings for Medicare and private payers, particularly in patients with high-risk conditions such as type 2 diabetes. More efficient use of resources is needed, including low-cost medication, to improve clinical outcomes and lower overall costs, especially in high-risk groups. Widening access to PD where it is safe and appropriate may help to reduce dialysis costs.

Parathyroidectomy and survival in a cohort of Italian dialysis patients: results of a multicenter, observational, prospective study

BACKGROUND

Severe secondary hyperparathyroidism (SHPT) is associated with mortality in end stage kidney disease (ESKD). Parathyroidectomy (PTX) becomes necessary when medical therapy fails, thus highlighting the interest to compare biochemical and clinical outcomes of patients receiving either medical treatment or surgery.

METHODS

We aimed to compare overall survival and biochemical control of hemodialysis patients with severe hyperparathyroidism, treated by surgery or medical therapy followed-up for 36 months. Inclusion criteria were age older than 18 years, renal failure requiring dialysis treatment (hemodialysis or peritoneal dialysis) and ability to sign the consent form. A control group of 418 patients treated in the same centers, who did not undergo parathyroidectomy was selected after matching for age, sex, and dialysis vintage.

RESULTS

From 82 Dialysis units in Italy, we prospectively collected data of 257 prevalent patients who underwent parathyroidectomy (age 58.2 ± 12.8 years; M/F: 44%/56%, dialysis vintage: 15.5 ± 8.4 years) and of 418 control patients who did not undergo parathyroidectomy (age 60.3 ± 14.4 years; M/F 44%/56%; dialysis vintage 11.2 ± 7.6 y). The survival rate was higher in the group that underwent parathyroidectomy (Kaplan-Meier log rank test = 0.002). Univariable analysis (HR 0.556, CI: 0.387-0.800, p = 0.002) and multivariable analysis (HR 0.671, CI:0.465-0.970, p = 0.034), identified parathyroidectomy as a protective factor of overall survival. The prevalence of patients at KDOQI targets for PTH was lower in patients who underwent parathyroidectomy compared to controls (PTX vs non-PTX: PTH < 150 pg/ml: 59% vs 21%, p = 0.001; PTH at target: 18% vs 37% p = 0.001; PTH > 300 pg/ml 23% vs 42% p = 0.001). The control group received more intensive medical treatment with higher prevalence of vitamin D (65% vs 41%, p = 0.0001), calcimimetics (34% vs 14%, p = 0.0001) and phosphate binders (77% vs 66%, p = 0.002).

CONCLUSIONS

Our data suggest that parathyroidectomy is associated with survival rate at 36 months, independently of biochemical control. Lower exposure to high PTH levels could represent an advantage in the long term.

Hypocalcemia Risk of Denosumab Across the Spectrum of Kidney Disease: A Population-Based Cohort Study

Denosumab can be used in patients with chronic kidney disease (CKD) but has been linked with cases of severe hypocalcemia. The incidence of and risk factors for hypocalcemia after denosumab use are not well established. Using linked health care databases at ICES, we conducted a population-based cohort study of adults >65 years old with a new prescription for denosumab or a bisphosphonate between 2012 and 2020. We assessed incidence of hypocalcemia within 180 days of drug dispensing and stratified results by estimated glomerular filtration rate (eGFR in mL/min/1.73 m² ). We used Cox proportional hazards to assess risk factors for hypocalcemia. There were 59,151 and 56,847 new denosumab and oral bisphosphonate users, respectively. Of the denosumab users, 29% had serum calcium measured in the year before their prescription, and one-third had their serum calcium checked within 180 days after their prescription. Mild hypocalcemia (albumin corrected calcium <2.00 mmol/L) occurred in 0.6% (95% confidence interval [CI] 0.6, 0.7) of new denosumab users and severe hypocalcemia (<1.8 mmol/L) in 0.2% (95% CI 0.2, 0.3). In those with an eGFR <15 or receiving maintenance dialysis, the incidence of mild and severe hypocalcemia was 24.1% (95% CI 18.1, 30.7) and 14.9% (95% CI 10.1, 20.7), respectively. In this group, kidney function and baseline serum calcium were strong predictors of hypocalcemia. We did not have information on over-the-counter vitamin D or calcium supplementation. In new bisphosphonate users, the incidence of mild hypocalcemia was 0.3% (95% CI 0.3, 0.3) with an incidence of 4.7% (95% CI 1.5, 10.8) in those with an eGFR <15 or receiving maintenance dialysis. In this large population-based cohort, we found that the overall risk of hypocalcemia with new denosumab use was low but increased substantially in those with eGFR <15 mL/min/1.73 m² . Future studies should investigate strategies to mitigate hypocalcemia. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Hungry bone syndrome after parathyroid surgery

INTRODUCTION

Data on the incidence rates of hungry bone syndrome after parathyroidectomy in patients on dialysis are inconsistent, as the published rates vary from 15.8% to 92.9%.

METHODS

Between 2009 and 2019, 120 hemodialysis patients underwent parathyroidectomy for secondary hyperparathyroidism at the Chang Gung Memorial Hospital. The patients were stratified into two groups based on the presence (n = 100) or absence (n = 20) of hungry bone syndrome after parathyroidectomy.

FINDINGS

Subtotal parathyroidectomy was the most common surgery performed (76.7%), followed by total parathyroidectomy with autoimplantation (23.3%). Pathological examination revealed parathyroid hyperplasia. Hungry bone syndrome developed within 0.3 ± 0.3 months and lasted for 11.1 ± 14.7 months. After surgery, compared with patients without hungry bone syndrome, patients with hungry bone syndrome had lower levels of nadir corrected calcium (P < 0.001), as well as lower nadir (P < 0.001) and peak (P < 0.001) intact parathyroid hormone levels. During 59.3 ± 44.0 months of follow-up, persistence and recurrence of hyperparathyroidism occurred in 25 (20.8%) and 30 (25.0%) patients, respectively. Furthermore, patients with hungry bone syndrome had a lower rate of persistent hyperparathyroidism than those without hungry bone syndrome (P < 0.001). Four patients (3.3%) underwent a second parathyroidectomy. Patients with hungry bone syndrome received fewer second parathyroidectomies than those without hungry bone syndrome (P < 0.001). Finally, a multivariate logistic regression model revealed that the preoperative blood ferritin level was a negative predictor of the development of hungry bone syndrome (P = 0.038).

DISCUSSION

Hungry bone syndrome is common (83.3%) after parathyroidectomy for secondary hyperparathyroidism in patients undergoing hemodialysis, and this complication should be monitored and managed appropriately.