Clinical epidemiology of parathyroidectomy in hemodialysis patients: The USRDS waves 1, 3, and 4 study

Changes in serum FGF23 and Klotho levels and calcification scores of the abdominal aorta after parathyroidectomy for secondary hyperparathyroidism

BACKGROUND

Changes of calcification scores of the abdominal aorta (CSAA) after total parathyroidectomy plus autotransplantation (TPX + AT) for symptomatic secondary hyperparathyroidism (SSHP) have never been reported.

METHODS

Forty-nine patients who successfully underwent TPX + AT for SSHP were enrolled; 13 patients who had regular hemodialysis were enrolled as controls. Preoperatively, patients' age, gender, and duration of dialysis were recorded. Serum Ca, P, alkaline phosphatase (Alk-ptase), intact parathyroid hormone (iPTH), vitamin D, FGF23, and Klotho levels, and CSAA were measured. One year postoperatively, these data were measured again. In the control group, these data were recorded and measured before and one year later.

RESULTS

Serum iPTH, Alk-ptase and FGF23 levels and CSAA of the study group were significantly higher than those of the control group. One year postoperatively, serum Ca, P, Alk-ptase, iPTH, and FGF23 levels and CSAA were significantly lower than those before surgery. Except for FGF23 levels, other items of the control group did not change significantly one year later, whereas the study group decreased CSAA more than the control group.

CONCLUSION

One year postoperatively, CSAA decreased.

A Prospective Study of the Efficacy, Safety and Pharmacokinetics of Enteral Moxifloxacin in the Treatment of Hemodialysis Patients with Pneumonia

Objectives To investigate the efficacy of oral moxifloxacin (MFLX) as a treatment for pneumonia in hemodialysis (HD) patients and the pharmacokinetic (PK) profile of MFLX after oral administration. Methods Thirteen adult patients who required HD due to chronic renal failure were enrolled in the present study, which was performed to investigate the treatment of community-acquired pneumonia in HD patients. A standard dose of MFLX (400 mg, once daily) was administered. The therapy was continued, discontinued, or switched to another antibiotic depending on the response of the pneumonia to MFLX. A population PK model was developed using the post-hoc method. Results In total, 13 HD patients with pneumonia (male, n=7; female, n=6) were enrolled in the present study. The evaluation on the 3rd day showed that treatment was successful in 11 patients (84.6%) and that 10 patients were cured (76.9%). In the one case in which MFLX treatment failed, the patient was cured by switching to ceftriaxone (CTRX) (2 g, intravenously) plus levofloxacin (LVFX) (250 mg, orally). The causative bacterium in this male patient was P. aeruginosa. It did not display resistance to fluoroquinolones. One patient had liver dysfunction due to MFLX. The estimated PK parameters of MFLX were as follows: AUC_0→24, 61.04±17.74 μg h/mL; C_max, 5.25±1.12 μg/mL; and C_trough, 1.15±0.45 μg/mL. The PK parameters of MFLX among the patients in whom adverse events occurred or in whom a cure was not achieved did not differ from those of the other patients to a statistically significant extent. Conclusion MFLX showed good efficacy and safety in HD patients with community-acquired pneumonia and the results of the PK analysis were favorable. Further prospective studies with larger numbers of patients will be needed to draw definitive conclusions.

Association between clinical variables and mortality after parathyroidectomy in maintenance hemodialysis patients

BACKGROUND

We investigated factors associated with all-cause mortality and cardiovascular disease (CVD)-associated mortality after parathyroidectomy (PTX) in patients on maintenance hemodialysis (HD).

METHODS

Our study population consisted of 161 consecutive HD patients who underwent PTX before 2009 and 354 consecutive HD patients without PTX as controls from those visiting the Kaohsiung Chang Gung Memorial Hospital, Taiwan between 2009 and 2013. All-cause and CVD mortality with clinical variables were compared in PTX and non-PTX HD patients.

RESULTS

PTX patients had significantly lower all-cause and CVD mortality than controls. Multivariate logistic regression analyses showed PTX patients had a lower odds ratio for all-cause mortality than those without (odds ratio = .35, 95% confidence interval = .16 to .74). Association analysis based on clinical variables revealed patients with higher hemoglobin, albumin, creatinine, and HD adequacy index-Kt/V levels had significantly decreased risk of all-cause mortality.

CONCLUSIONS

PTX in HD patients reduces the risk of death.

Parathyroidectomy Associates with Reduced Mortality in Taiwanese Dialysis Patients with Hyperparathyroidism: Evidence for the Controversy of Current Guidelines

Parathyroidectomy is recommended by the clinical guidelines for dialysis patients with unremitting secondary hyperparathyroidism (SHPT). However, the survival advantage of parathyroidectomy is debated because of the selection bias in previous studies. To minimize potential bias in the present nationwide cohort study, we enrolled only dialysis patients who had undergone radionuclide parathyroid scanning to ensure all patients had severe SHPT. The parathyroidectomized patients were matched with the controls based on propensity score for parathyroidectomy. Mortality hazard was estimated using multivariate Cox proportional hazard models adjusting for comorbidities before scanning (model 1) or over the whole study period (model 2). Our results showed that among the 2786 enrolled patients, 1707 underwent parathyroidectomy, and the other 1079 were controls. The crude mortality rates were lower in the parathyroidectomized patients than in the controls. In adjusted analyses for the population matched on propensity score, parathyroidectomy was associated with a significant 20% to 25% lower risk for all-cause mortality (model 1: hazard ratio 0.76, 95% confidence interval 0.61 to 0.94; model 2: hazard ratio 0.80, 95% confidence internal 0.64 to 0.98). We concluded that parathyroidectomy was associated with a reduced long-term mortality risk in dialysis patients with severe SHPT.

Relationship between parathyroid mass and parathyroid hormone level in hemodialysis patients with secondary hyperparathyroidism

Background

To evaluate the influence of parathyroid mass on the regulation of parathyroid hormone (PTH) secretion, we investigated the relationship between the resected parathyroid gland in total parathyroidectomy and the parathyroid hormone level in hemodialysis patients with secondary hyperparathyroidism.

Methods

From January 2009 to July 2014, 223 patients undergoing total parathyroidectomy were included. The size and the weight of parathyroid gland were measured during the operation.

Results

874 parathyroid glands were removed. A positive correlation was identified between the size and the weight of resected parathyroid glands. We found that both the preoperative PTH and the reduction of PTH were significantly correlated with the size and the weight of parathyroid glands in a positive manner. However, in the subgroup of patients with PTH < 1000 pg/ml, no significant correlation was found.

Conclusions

Larger parathyroid gland secretes more PTH and high level of serum PTH usually indicated that surgical removal might be required. However, since PTH levels could be influenced by the pharmaceutical drug, the large size of parathyroid gland might be used as a much more appropriate guide that indicates the requirement of surgery treatment even when the parathyroid hormone was less than 1000 pg/ml.

Temporal trends and risk factors for parathyroidectomy in the Swedish dialysis and transplant population - a nationwide, population-based study 1991 - 2009

BACKGROUND

Many patients on renal replacement therapy (RRT) require parathyroidectomy (PTX). Trends and current rates of PTX on a national level are not known. Furthermore, it is not completely clear which factors influence rates of PTX. Thus, our aim was to investigate the incidence, regional distribution and factors associated with PTX as well as possible temporal changes, in the Swedish RRT population.

METHODS

From the Swedish Renal Registry we extracted data on 20 015 patients on RRT between 1991 and 2009. In these, 679 incident PTX (3.4%) were identified by linkage with the National Inpatient Registry, and the Scandinavian Quality Registry for Thyroid Parathyroid and Adrenal Surgery. Poisson models were used to estimate rates per calendar year, adjusted for risk factors such as gender, age, time with renal transplant, and underlying cause of renal disease.

RESULTS

The PTX rate was 8.8/1 000 person-years. There was a significant increase 2001-2004 after which the rate fell, as compared with year 2000. Female gender, non-diabetic cause of renal disease and age between 40-55 were all associated with an increased frequency of PTX.

CONCLUSION

The rise in PTX rates after year 2000 might reflect increasing awareness of the potential benefits of PTX. The introduction of calcimimetics and paricalcitol might explain the decreased rate after 2005.

Effect of cinacalcet availability and formulary listing on parathyroidectomy rate trends

Background

Recent trends in parathyroidectomy rates are not known. Our objective was to investigate the trend in parathyroidectomy rates between 2001 and 2010, and to evaluate if the availability and reimbursement of cinacalcet modified that trend.

Methods

Using a provincial administrative database, we included all adult patients receiving chronic dialysis treatments between 2001 and 2010 (incident and prevalent) in a time series analysis. The effect of cinacalcet availability on parathyroidectomy bimonthly rates was modeled using an ARIMA intervention model using different cut-off dates: September 2004 (Health Canada cinacalcet approval), January 2005, June 2005, January 2006, June 2006 (date of cinacalcet provincial reimbursement), and January 2007.

Results

A total of 12 795 chronic dialysis patients (mean age 64 years, 39% female, 82% hemodialysis) were followed for a mean follow-up of 3.3 years. During follow-up, 267 parathyroidectomies were identified, translating to an average rate of 7.0 per 1000 person-years. The average parathyroidectomy rate before cinacalcet availability was 11.4 /1000 person-years, and 3.6 /1000 person-years after cinacalcet public formulary listing. Only January 2006 as an intervention date in the ARIMA model was associated with a change in parathyroidectomy rates (estimate: -5.58, p = 0.03). Other intervention dates were not associated with lower parathyroidectomy rates.

Conclusions

A reduction in rates of parathyroidectomy was found after January 2006, corresponding to cinacalcet availability. However, decreased rates may be due to other factors occurring simultaneously with cinacalcet introduction and further studies are needed to confirm these findings.

Improved long-term survival of dialysis patients after near-total parathyroidectomy

BACKGROUND

Severe secondary hyperparathyroidism, which is associated with life-threatening complications, can develop in dialysis-dependent end-stage renal disease patients. The aim of this study was to compare short- and long-term mortality in dialysis patients who underwent near-total parathyroidectomy (NTPTX) and matched nonoperated controls.

STUDY DESIGN

We identified 150 dialysis patients who underwent NTPTX (1993-2009) at our institution and compared them with 1,044 nonoperated control patients identified in the US Renal Data System registry, matched for age, sex, race, diabetes as cause of kidney failure, years on dialysis, and dialysis modality. Survival outcomes were estimated using multivariable Cox proportional hazards models with stratification on the matching sets, adjusted for cardiovascular comorbidities, smoking, inability to ambulate/transfer, and payor status.

RESULTS

During a follow-up of a mean of 3.6 years (range 0.1 month to 16.4 years), NTPTX patients had a significant reduction in the long-term risk of all-cause death (hazard ratio = 0.68; 95% CI, 0.52-0.89; p = 0.006) compared with controls. Thirty-day mortality rates for NTPTX patients and controls were 246 vs 105 per 1,000 person-years (p = 0.21). In adjusted analyses, NTPTX patients had a 37% reduced risk of all-cause death and a 33% reduced risk of cardiovascular death compared with controls. A durable reduction in mean parathyroid hormone was observed after NTPTX; from 1,776 ± 1,416.6 pg/mL to 301 ± 285.7 pg/mL (p < 0.0001).

CONCLUSIONS

In our center, NTPTX in dialysis patients was associated with a significant reduction in long-term risk of death compared with matched control patients, without a significantly increased short-term risk.

A cost-utility analysis of cinacalcet in secondary hyperparathyroidism in five European countries

BACKGROUND AND OBJECTIVE

A probabilistic patient-level Markov model was previously developed to simulate lifetime clinical and economic outcomes of cinacalcet treatment in secondary hyperparathyroidism (SHPT) patients using local data from Italy. The present study extends the application of the model to four other European countries - Spain, Portugal, Switzerland and the Czech Republic - in order to assess the consistency of results.

METHODS

Cinacalcet influences the levels of parathyroid hormone, serum calcium and phosphorous. Our simulation was based on data from the OPTIMA (Open-Label, Randomized Study Using Cinacalcet to Improve Achievement of KDOQI Targets in Patients with End-Stage Renal Disease) randomized controlled trial and from published correlations between bone-metabolism parameters, mortality and morbidity (cardiovascular [CV] events, fractures and parathyroidectomy). Local epidemiological and cost data for dialysis, drugs and event management were incorporated into the model. The simulation horizon was patient lifetime; standard treatment for SHPT (vitamin D sterols and phosphate binders) and cinacalcet plus standard treatment were compared. Effectiveness was measured in terms of life expectancy (LE) and quality-adjusted life expectancy (QALE). Health utility indexes derived from published literature took into account dialysis, CV events and fractures.

RESULTS

The simulated mean LE extension in patients receiving cinacalcet was 1.20 life-years (LY) in Italy, 1.10 LY in Spain, 1.18 LY in Portugal, 1.10 LY in the Czech Republic and 1.40 LY in Switzerland. QALE increase was 0.89, 0.82, 0.89, 0.80 and 1.01 QALY in the same countries, respectively. The incremental cost-effectiveness ratio (ICER) result was €23,500/LY and €31,600/QALY in Italy, €21,800/LY and €29,300/QALY in Spain, €23,700/LY and €31,200/QALY in Portugal, €29,700/LY and €40,800/QALY in the Czech Republic and €24,700/LY and €34,200/QALY in Switzerland. Including dialysis costs as a part of the total costing doubled the ICER, from a minimum of €42,800/LY in Spain to a maximum of €82,800/LY in Switzerland and in the range from €57,500/QALY (Spain) to €114,700/QALY (Switzerland).

CONCLUSION

Taking into consideration the limited clinical, epidemiological and health economics data available, cinacalcet treatment showed a relatively good cost-effectiveness profile in all the countries analysed, despite the differences in their healthcare systems and economic wealth.

Symmetrical craniofacial hypertrophy in patients with tertiary hyperparathyroidism and high-dose cinacalcet exposure

We are reporting on a series of two patients with end-stage renal disease on hemodialysis, presented for surgical parathyroidectomy secondary refractory hyperparathyroidism. Both patients had failed maximized medical managements, including higher-than-usual doses of the calcimimetic cinacalcet (270 and 180 mg/day, respectively). On physical exam, both patients had marked symmetrical craniofacial hypertrophy with coarse distortion of facial features, similar in appearance to past reports of Sagliker syndrome. On X-ray and computed tomographic exam, they had peculiar areas of bone absorption on the skull, imitating the radiologic appearance of multiple myeloma. Bone biopsy of the maxilla, however, did not show the expected brown tumor, but rather described only fibrosis and reactive bone formations. This phenotype developed while being on cinacalcet, progressed despite escalation of therapy, and improved only after parathyroidectomy. Both patients developed massive "hungry bone syndrome" after parathyroidectomy necessitating prolonged i.v. calcium infusion. This pattern of severe facial distortion likely represented an adverse consequence of severe tertiary hyperparathyroidism, along with supraphysiologic dose of cinacalcet administration and 25-hydroxy vitamin D deficiency in sensitive individuals. The genetic base of this observation remained unexplained.

Cost-effectiveness of cinacalcet in secondary hyperparathyroidism in the United States

OBJECTIVE

Cinacalcet has been used in controlling secondary hyperparathyroidism (SHPT) in dialysis patients since 2004, but its full economic evaluation has not been conducted from the US perspective. This study assesses the cost-effectiveness of cinacalcet and low-dose vitamin D for the treatment of SHPT in dialysis patients compared with flexible vitamin D.

METHODS

A lifetime patient-level simulation model was developed using ADVANCE trial data, including biomarker levels: parathyroid hormone, calcium, and phosphorus. The impact of the biomarkers on mortality, cardiovascular events, fractures, and parathyroidectomy were estimated from literature: Block, an observational study; Cunningham, a combined analysis of four randomized trials of cinacalcet; and Danese, a study investigating the effect of duration in recommended targets. Baseline event rates were derived from the large dialysis organizations registries. One-way and probabilistic sensitivity analyses (PSA) were conducted.

RESULTS

The cost-effectiveness ratio for cinacalcet compared with standard of care (vitamin D and phosphate binders) was $54,560 and $72,456/quality-adjusted-life-year (QALY) gained or an incremental cost of $3155 and $2638 per year alive for the Block and Danese variants, respectively. In the Cunningham variant, cost-effectiveness ratio for cinacalcet was $5064/QALY gained or a cost saving of $1068 per year. The difference in the results of the Cunningham variant vs other variants can be explained by the favorable impact of cinacalcet on outcomes, specifically cardiovascular events observed in the Cunningham study. The PSA showed 98% likelihood for cinacalcet to be cost-effective at $100,000/QALY threshold.

LIMITATIONS

Observational data assessing effects on clinical outcomes, trial restriction to use calcium-containing phosphate binders, no utility data in SHPT dialysis population, and insufficient evidence on long-term impact of cinacalcet and vitamin D on biochemical markers.

CONCLUSIONS

Cinacalcet treatment is cost-effective for treatment of SHPT in the US. Due to cost offsets, cinacalcet can reduce annual costs in some scenarios.

Cinacalcet: a pharmacoeconomic review of its use in secondary hyperparathyroidism in end-stage renal disease

This article provides an overview of the clinical profile of the calcimimetic agent cinacalcet (Mimpara®, Sensipar®) in the treatment of patients with secondary hyperparathyroidism (SHPT) undergoing dialysis for end-stage renal disease (ESRD), followed by a comprehensive review of pharmacoeconomic analyses with cinacalcet in this patient population. Most patients with ESRD undergoing dialysis develop SHPT, which is associated with disturbances in bone mineral metabolism and the development of fractures, cardiovascular disease and other clinical events. Standard treatment of SHPT includes phosphate binders and active vitamin D derivatives. However, standard treatment alone seldom achieves recommended target plasma or serum levels of parathyroid hormone (PTH), calcium and phosphorous. The addition of cinacalcet to standard therapy in patients with SHPT undergoing dialysis for ESRD improves the likelihood of achieving target biochemical levels compared with standard therapy alone. On the basis of association studies, improvements in these intermediate endpoints are likely to reduce the risk of clinical events, such as fractures and cardiovascular disease. Therefore, part of the acquisition cost of cinacalcet is likely to be offset by reductions in other healthcare resource use, such as reductions in costs associated with a lower likelihood of clinical events, as well as potential reductions in dosages of standard treatment. A number of pharmacoeconomic analyses across various country settings indicate that cinacalcet plus standard therapy is cost effective relative to standard therapy alone if dialysis costs are excluded, or that early initiation of cinacalcet is cost effective compared with delaying cinacalcet treatment until PTH levels become very uncontrolled. However, across analyses with cinacalcet, results were variable and not always favourable. This wide range of results stems from differences in selection of data sources used to populate the models, regional differences in healthcare resource use and costs, as well as other factors. Future cost-effectiveness analyses with cinacalcet should incorporate data on hard clinical outcomes from the EVOLVE study once this information becomes available.

[Surgical treatment of secondary hyperparathyroidism in patients with chronic renal failure]

OBJECTIVE

To identify the indications for subtotal parathyroidectomy (PTX) in secondary hyperparathyroidism (SHPT) and report postoperative, early and late complications of PTX.

PATIENTS AND METHODS

We conducted a retrospective study of subjects with chronic renal failure operated in Tunisian hospitals who received subtotal PTX over 10 years from January 1997 to December 2007. We analyzed the clinical, biological and radiological parameters pre- and postoperatively.

RESULTS

We included 70 patients with average age of 39.4 years, 55.7% men and 44.3% in dialysis for 7.75 ± 4.8 years before PTX. The initial nephropathy was interstitial in 50% of cases. No cases of diabetic nephropathy have been reported. The clinical signs were bone pain (88.6%), muscle pain (85.6%), pruritus (81.4%). Radiological signs of osteitis fibrosa were observed in the majority of patients mainly resorption of extremities (92.9%), thinning of cortical (85.7%) and osteosclerosis (87.1%). The most common indication of PTX (85.7% of cases) was the persistence of serum PTH of more than 800 pg/ml associated with hypercalcemia and/or hyperphosphatemia refractory to medical treatment. A subtotal PTX (3/4 or 7/8) was performed after ultrasound and scintigraphy in the majority of cases. The histology of the parathyroid glands showed diffuse hyperplasia (51.4%), nodular hyperplasia (45.7%) and adenoma (2.8%). The postoperative evolution was marked by an improvement of the clinical and radiological criteria in 80% of cases. A PTH level of less than 15 pg/ml was rarely observed (10% of cases), and a PTH level of more than 300 pg/ml concerned 13% of patients. We noted a low morbidity and mortality (no cases laryngeal paralysis or cervical hematoma).

CONCLUSION

Surgical treatment of SHPT in Tunisia is very effective in our experience. The biological results are comparable to treatment with calcimimetics, not available in Tunisia and whose price is higher. An early treatment of disorders of bone and mineral metabolism should reduce the incidence of SHPT.

Optimizing bone health in chronic kidney disease

Phosphocalcic metabolism disorders often complicate chronic kidney disease (CKD) and worsen as kidney function declines, with a consequence on bone structural integrity. The risk of fracture exceeds that of the normal population in both patients with pre-dialysis CKD and end-stage renal disease (ESRD). The increasing incidence of CKD, the high mortality rate induced by hip fracture, the decreased quality of life and economic burden of fragility fracture make the renal bone disorders a major problem of public health around the world. Optimizing bone health in CKD patients should be a priority. Bone biopsy is invasive. Dual-energy X-ray absorptiometry, commonly used to screen individuals at risk of fragility fracture in the general population, is not adequate to assess advanced CKD because it does not discriminate fracture status in this population. New non-invasive three-dimensional high-resolution imaging techniques, distinguishing trabecular and cortical bone, appear to be promising in the assessment of bone strength and might improve bone fracture prediction in this population. Therapeutic intervention in the chronic kidney disease-mineral and bone disorders (CKD-MBD) should begin early in the course of CKD to maintain serum concentration of biological parameters involved in mineral metabolism in the normal recommended ranges, prevent the development of parathyroid hyperplasia, prevent extra-skeletal calcifications and preserve skeletal health. In this paper, we review studies of mineral and bone disorders in patients with CKD and ESRD, the utility of current techniques to assess bone health and the preventive and therapeutic strategies for managing CKD-MBD.

Economic evaluation of cinacalcet in the treatment of secondary hyperparathyroidism in Italy

BACKGROUND

Imbalanced levels of parathyroid hormone (PTH), serum calcium (Ca) and phosphorous (P) are associated with an increased risk of cardiovascular (CV) death and fracture in dialysis patients with secondary hyperparathyroidism (SHPT). The calcimimetic agent cinacalcet can attenuate the mineral and hormonal imbalances characteristic of SHPT and may improve outcomes in such patients. Here we describe a cost-utility analysis of cinacalcet for SHPT in dialysis patients in Italy.

METHODS

We developed a probabilistic Markov model to simulate the effect of cinacalcet on Ca, P and PTH levels in dialysis patients with SHPT, based on data from a European, multicentre, open-label study. The model then correlated these levels with mortality and morbidity (CV events, fractures and parathyroidectomies) using data from the literature, and incorporated Italian data for dialysis, drugs and management of events according to the national cost structure. The simulation horizon was patient lifetime; simulated treatment alternatives were standard treatment (mainly vitamin D sterols and phosphate binders) and cinacalcet + standard treatment. A 3.5% discount rate was applied to life expectancy (LE), quality-adjusted life-expectancy (QALE), costs and times below the upper ranges (time in range [TiR]) recommended by the National Kidney Foundation - Kidney Disease Outcomes Quality initiative for PTH, Ca, P and Ca × P. Utilities were derived from the published literature and took into account dialysis and the impairment of quality of life due to the occurrence of CV events and fractures. Costs were evaluated in year 2009 values from the perspective of the Italian National Healthcare System.

RESULTS

Baseline results were calculated with 10,000 iterations. Compared with standard treatment alone, addition of cinacalcet was associated with a mean (SD) increase in TiR of 5.26 (6.59), 3.63 (6.87), 1.70 (6.66) and 2.68 (5.55) discounted patient-years for PTH, Ca and P, respectively, and combined PTH, Ca, P and Ca × P. Cinacalcet increased LE by 1.20 (3.75) life-years (LYs) and QALE by 0.89 (2.59) QALYs. When including the cost for dialysis, the incremental cost-effectiveness ratio (ICER) was €50,012 per LY and €67,361 per QALY, while, if dialysis costs were not included, the ICER was €23,473 per LY and €31,616 per QALY.

CONCLUSIONS

The results suggest that cinacalcet treatment could be considered cost effective for treatment of SHPT in the Italian healthcare setting, but further investigations are needed to confirm these findings.