Economic evaluations of interventions to manage hyperphosphataemia in adult haemodialysis patients: A systematic review

The efficacy and safety of cuttlebone for lowering serum phosphate in patients with end-stage renal disease: a meta-analysis of randomized controlled trials

Background: The efficacy of cuttlebone for treating hyperphosphatemia in patients with end-stage renal disease and its safety remained unclear. Methods: Randomized controlled trials comparing the efficacy of cuttlebone with conventional interventions were retrieved from MEDLINE, EMBASE, Cochrane Library, Airiti Library, and other major Chinese databases until 1 February 2023. The primary outcome was circulating phosphate concentration, while secondary outcomes included circulating calcium and intact parathyroid hormone levels, calcium-phosphorus product, and treatment-related side-effects. Results: Analysis of nine studies published between 2000 and 2019 including 726 participants showed a lower circulating phosphate concentration in the cuttlebone group than in controls [mean difference (MD) = -0.23, 95% CI: -0.39 to -0.06, p = 0.006, I2 = 94%, 726 patients] and a dose-dependent effect of cuttlebone against hyperphosphatemia. Therapeutic benefits were noted after both short-term (1-2 months) and long-term (3-6 months) treatments. Besides, patients receiving hemodialysis showed a better response to cuttlebone than those receiving peritoneal dialysis. There was no difference in circulating calcium level (mean difference = 0.03, 95% CI: -0.01 to 0.07, p = 0.17, I2 = 34%, 654 patients), while patients receiving cuttlebone showed lower circulating iPTH level and calcium-phosphorus product (MD = -43.63, 95% CI: -74.1 to -13.16, p = 0.005, I2 = 76%, 654 patients), (MD = -0.38, 95% CI: -0.38 to -0.01, p = 0.04, I2 = 83%, 520 patients). No difference in the risks of constipation, gastrointestinal discomfort, and elevated blood calcium was noted between the two groups. Conclusion: Compared with conventional phosphate-binding agents, cuttlebone more efficiently suppressed hyperphosphatemia with a dose-dependent effect. The limited number of included studies warrants further clinical investigations to verify our findings. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023396300.

Past, Present, and Future of Phosphate Management

Cardiovascular (CV) disease (CVD) accounts for >50% of deaths with known causes in patients on dialysis. Elevated serum phosphorus levels are an important nontraditional risk factor for bone mineral disease and CVD in patients with chronic kidney disease (CKD). Given that phosphorus concentrations drive other disorders associated with increased CV risk (e.g., endothelial dysfunction, vascular calcification, fibroblast growth factor-23, parathyroid hormone), phosphate is a logical target to improve CV health. Phosphate binders are the only pharmacologic treatment approved for hyperphosphatemia. Although their safety has improved since inception, the mechanism of action leads to characteristics that make ingestion difficult and unpleasant; large pill size, objectionable taste, and multiple pills required for each meal and snack make phosphate binders a burden. Side effects, especially those affecting the gastrointestinal (GI) system, are common with binders, often leading to treatment discontinuation. The presence of “hidden” phosphates in processed foods and certain medications makes phosphate management even more challenging. Owing to these significant issues, most patients on dialysis are not consistently achieving and maintaining target phosphorus concentrations of <5.5 mg/dl, let alone more normal levels of <4.5 mg/dl, indicating novel approaches to improve phosphate management and CV health are needed. Several new nonbinder therapies that target intestinal phosphate absorption pathways have been developed. These include EOS789, which acts on the transcellular pathway, and tenapanor, which targets the dominant paracellular pathway. As observational evidence has established a strong association between phosphorus concentration and clinical outcomes, such as mortality, phosphate is an important target for improving the health of patients with CKD and end-stage kidney disease (ESKD).

Evaluation of the cost-utility of phosphate binders as a treatment option for hyperphosphatemia in chronic kidney disease patients: a systematic review and meta-analysis of the economic evaluations

BACKGROUND

Uncontrolled hyperphosphatemia in chronic kidney disease (CKD) patients commonly results in vascular calcification leading to increased risk of cardiovascular disease. Phosphate binders (PBs) are used for hyperphosphatemia and can be calcium-based (CBPBs) or non-calcium-based (NCBPBs), the latter being more expensive than CBPBs. In this study, we used meta-analysis approaches to assess the cost-utility of PBs for hyperphosphatemia in CKD patients.

METHODS

Relevant studies published prior to June 2019 were identified from PubMed, Scopus, the Cochrane Library, the National Health Service Economic Evaluation Database, and the Cost-Effectiveness Analysis Registry. Studies were eligible if they included CKD patients with hyperphosphatemia, compared any PBs and reported economic outcomes. Meta-analysis was applied to pool incremental net benefit (INB) across studies stratified by country income.

RESULTS

A total of 25 studies encompassing 32 comparisons were eligible. Lanthanum carbonate, a NCBPB, was a more cost-effective option than CBPBs in high-income countries (HICs), with a pooled INB of $3984.4 (599.5-7369.4), especially in pre-dialysis patients and used as a second-line option with INBs of $4860.2 (641.5-9078.8), $4011.0 (533.7-7488.3), respectively. Sevelamer, also a NCBPB, was not more cost-effective as a first-line option compared to CBPBs with a pooled INB of $6045.8 (- 23,453.0 to 35,522.6) and $34,168.9 (- 638.0 to 68,975.7) in HICs and upper middle-income countries, respectively.

CONCLUSIONS

Lanthanum carbonate was significantly more cost-effective than CBPBs as a second-line option for hyperphosphatemia in pre-dialysis patients in HICs. However, the use of sevelamer is not more cost-effective as a first-line option compared to CBPBs.

Effect of Intradialytic Exercise on Hyperphosphatemia and Malnutrition

Intradialytic exercise (IDE) is not routinely prescribed in hemodialysis (HD) units despite its potential benefits on patients' outcomes. This study was the first in the United Arab Emirates to examine the effect of aerobic IDE on hyperphosphatemia, malnutrition, and other health outcomes among HD patients. Participants were chosen from the largest HD unit in Sharjah Emirate for a quasi-experimental intervention with pre and post evaluation. The study lasted for 12 months. Study parameters were collected at baseline, post intervention, and follow-up. The intervention included a moderate-intensity aerobic IDE of 45 min per HD session; intensity was assessed using the Borg Scale. Patients were educated on the importance of exercise. Study outcomes were serum phosphorus (P), malnutrition inflammation score (MIS), quality of life (QOL), and pertinent blood tests. Forty-one eligible consenting HD patients were included in the study. Results at follow-up showed a non-significant reduction in P (p = 0.06) in patients who were hyperphosphatemic at baseline, but not in the sample as whole. MIS did not deteriorate throughout the study (p = 0.97). IDE resulted in a non-significant increase in the QOL visual analogue scale (p = 0.34). To conclude, aerobic IDE for 45 min is safe and could be beneficial, especially for hyperphosphatemic patients.

A systematic review of the economic evaluations of non-calcium-containing phosphate binders, sevelamer and Lanthanum, in end-stage renal disease patients with hyperphosphatemia

INTRODUCTION

End-stage renal disease is associated with significant comorbidity and mortality. Among its implications, hyperphosphatemia constitutes a consistent and independent risk factor. The use of benchmark treatment, low-cost calcium-based binders declined due to a potential calcification effect on coronary arteries.

AREAS COVERED

Given the increasing prevalence of end-stage renal disease and the high cost of hyperphosphatemia's new primary modality, the non-calcium based phosphate binders, we set-off to systematically assess the economic evaluations of non-calcium containing phosphate binders, sevelamer and lanthanum. The study was performed based on a systematic review of the economic evaluations of sevelamer and lanthanum. The cost-effectiveness profile of the two non-calcium-containing Phosphate Binders compared to calcium-based phosphate binders depends on several factors such as future dialysis costs, utility values, age, survival, and phosphorus levels.

EXPERT OPINION

The comparison between the two agents is rather inconclusive; nevertheless, current review suggests that non-calcium-based phosphate binders may yield a positive cost-effectiveness ratio in patients with inadequate phosphorus management and patient with longer life-expectancy. It is crucial that the literature is endowed with more data, specifically on survival, future dialysis costs, and calcification.

A bundled phosphate control intervention (4Ds) for adults with end-stage kidney disease receiving haemodialysis: A cluster randomized controlled trial protocol

AIM

To evaluate the effectiveness of a bundled self-management intervention (Taking control of your phosphate with the 4Ds) to improve phosphate control among adults receiving haemodialysis.

BACKGROUND

Hyperphosphataemia occurs in end-stage kidney disease and is associated with increased morbidity and mortality. While hyperphosphataemia can be managed through four methods (food, drinks, drugs and dialysis) adherence to these methods is challenging for patients. Studies also tend to focus on one method of phosphate control rather than bundling all methods together into a theoretically driven intervention.

DESIGN

A multisite cluster randomized controlled trial with repeated measures.

METHODS

Adults receiving haemodialysis with high serum phosphate levels (>1.6 millimoles per litre for at least 3 months) will be cluster randomized to standard care or intervention according to haemodialysis treatment shift. Informed by social cognitive theory, the intervention focuses on improving self-efficacy and incorporates the "teach-back" method of patient education. The intervention brings together essential phosphate control strategies of diet, drinks, drugs (phosphate binders) and dialysis prescription in a 12-week self-management education programme. The primary outcome is serum phosphate level. Secondary outcomes are knowledge of and adherence to phosphate control strategies and self-efficacy for managing kidney disease.

DISCUSSION

Efforts to improve phosphate control have been undertaken although the optimal approach remains unclear. This study will make an important contribution to building an evidence base of phosphate control nursing intervention that can be delivered during routine haemodialysis.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry Number ACTRN12617000703303.

Targeting Gastrointestinal Transport Proteins to Control Hyperphosphatemia in Chronic Kidney Disease

Management of hyperphosphatemia in patients with dialysis-dependent chronic kidney disease remains a major challenge, requiring a multifaceted approach that includes dietary phosphate restriction, dialysis, and phosphate binders. However, these treatments fail to meet serum phosphate targets in many patients, potentially further exacerbating the significant morbidity and mortality burden associated with the disease. Recent advances in our understanding of the mechanisms underlying phosphate homeostasis have shed new light on the issue and suggest that gastrointestinal transport proteins may be promising targets for new hyperphosphatemia treatments. Drugs that inhibit or downregulate these transport proteins, and thus reduce phosphate uptake from the gut, may overcome some of the limitations of existing phosphate-lowering strategies, such as interdialytic rises in serum phosphate levels, poor adherence to dietary and phosphate-binder regimens, and maladaptive responses that can increase gastrointestinal phosphate absorption. Here, we review the latest preclinical and clinical data for two candidates in this novel drug class: tenapanor, a small-molecule inhibitor of the sodium/hydrogen ion-exchanger isoform 3, and nicotinamide, an inhibitor of sodium-phosphate-2b cotransporters. We also discuss how potential synergies in their mechanisms of action suggest that coadministering phosphate binders with sodium-phosphate-2b cotransporter inhibitors may yield additive benefits over traditional phosphate-binder therapy.

Phosphate-control adherence in hemodialysis patients: current perspectives

OBJECTIVES

This review summarizes factors relevant for adherence to phosphate-control strategies in dialysis patients, and discusses interventions to overcome related challenges.

METHODS

A literature search including the terms "phosphorus", "phosphorus control", "hemo-dialysis", "phosphate binder medications", "phosphorus diet", "adherence", and "nonadherence" was undertaken using PubMed, PsycInfo, CINAHL, and Embase.

RESULTS

Hyperphosphatemia is associated with cardiovascular and all-cause mortality in dialysis patients. Management of hyperphosphatemia depends on phosphate binder medication therapy, a low-phosphorus diet, and dialysis. Phosphate binder therapy is associated with a survival benefit. Dietary restriction is complex because of the need to maintain adequate protein intake and, alone, is insufficient for phosphorus control. Similarly, conventional hemodialysis alone is insufficient for phosphorus control due to the kinetics of dialytic phosphorus removal. Thus, all three treatment approaches are important contributors, with dietary restriction and dialysis as adjuncts to the requisite phosphate binder therapy. Phosphate-control adherence rates are suboptimal and are influenced directly by patient, provider, and phosphorus-control strategy-related factors. Psychosocial factors have been implicated as influential "drivers" of adherence behaviors in dialysis patients, and factors based on self-motivation associate directly with adherence behavior. Higher-risk subgroups of nonadherent patients include younger dialysis patients and non-whites. Provider attitudes may be important - yet unaddressed - determinants of adherence behaviors of dialysis patients.

CONCLUSION

Adherence to phosphate binders, low-phosphorus diet, and dialysis prescription is suboptimal. Multicomponent strategies that concurrently address therapy-related factors such as side effects, patient factors targeting self-motivation, and provider factors to improve attitudes and delivery of culturally sensitive care show the most promise for long-term control of phosphorus levels. Moreover, it will be important to identify patients at highest risk for lack of control, and for programs to be ready to deliver flexible person-centered strategies through training and dedicated resources to align with the needs of all patients.

Cross-Sectional Assessment of Achievement of Therapeutic Goals in a Canadian Multidisciplinary Clinic for Patients With Advanced Chronic Kidney Disease

Background

The implementation of advanced chronic kidney disease (CKD) multidisciplinary clinics has now demonstrated their effectiveness in delaying and even avoiding dialysis for patients with CKD. However, very little has been documented on the management and achievement of targets for a number of parameters in this context.

Objective

Our goal was to assess our multidisciplinary clinic therapy performance in relation to the targets for hypertension, anemia, and calcium phosphate assessment.

Methods

Design and setting

A cross-sectional descriptive study was conducted with a cohort including all patients followed up in our multidisciplinary clinic in July 2014.

Measurements

Comorbidity, laboratory, and clinical data were collected and compared with the recommendations of scientific organizations.

Results

The cohort included 128 patients, 37.5% of whom were women. Mean follow-up time was 26.6 ± 25.1 months and mean estimated glomerular filtration rate (eGFR) was 14.0 ± 4.7 mL/min/1.73 m². A total of 24.2% of patients with diabetes achieved blood pressure targets of <130/80 mm Hg, while 56.5% of patients without diabetes achieved targets of <140/90 mm Hg. Hemoglobin of patients treated with erythropoiesis-stimulating agents was 100 to 110 g/L in 36.2% of the patients, below 100 for 39.7% of them, and above 110 for 24.1%, whereas 67.2% were within the acceptable limits of 95 to 115 g/L. In addition, 63.4% of patients had a serum phosphate of <1.5 mmol/L, and 90.9% of patients had total serum calcium <2.5 mmol/L.

Limitations

Our study is a single center study with the majority of our patients being Caucasian. This limits the generalizability of our findings.

Conclusion

The control rates of various parameters were satisfactory given the difficult clinical context, but could be optimized. We publish these data in the hope that they are helpful to others engaged in quality improvement in their own programs or more generally.

Cost-Effectiveness of First-Line Sevelamer and Lanthanum versus Calcium-Based Binders for Hyperphosphatemia of Chronic Kidney Disease

BACKGROUND

Phosphate binders are used to treat hyperphosphatemia among patients with chronic kidney disease (CKD).

OBJECTIVES

To conduct an economic evaluation comparing calcium-free binders sevelamer and lanthanum with calcium-based binders for patients with CKD.

METHODS

Effectiveness data were obtained from a recent meta-analysis of randomized trials. Effectiveness was measured as life-years gained and translated to quality-adjusted life-years (QALYs) using utility weights from the literature. A Markov model consisting of non-dialysis-dependent (NDD)-CKD, dialysis-dependent (DD)-CKD, and death was developed to estimate the incremental costs and effects of sevelamer and lanthanum versus those of calcium-based binders. A lifetime horizon was used and both costs and effects were discounted at 1.5%. All costs are presented in 2015 Canadian dollars from the Canadian public payer perspective. Results of probabilistic sensitivity analysis were presented using cost-effectiveness acceptability curves. Sensitivity analyses were conducted for risk pooling methods, omission of dialysis costs, and persistence of drug effects on mortality.

RESULTS

Sevelamer resulted in an incremental cost-effectiveness ratio of $106,522/QALY for NDD-CKD and $133,847/QALY for DD-CKD cohorts. Excluding dialysis costs, sevelamer was cost-effective in the NDD-CKD cohort ($5,847/QALY) and the DD-CKD cohort ($11,178/QALY). Lanthanum was dominated regardless of whether dialysis costs were included.

CONCLUSIONS

Existing evidence does not clearly support the cost-effectiveness of non-calcium-containing phosphate binders (sevelamer and lanthanum) relative to calcium-containing phosphate binders in DD-CKD patients. Our study suggests that sevelamer may be cost-effective before dialysis onset. Because of the remaining uncertainty in several clinically relevant outcomes over time in DD-CKD and NDD-CKD patients, further research is encouraged.

Cost-effectiveness of dedicated dietitians for hyperphosphatemia management among hemodialysis patients in Lebanon: results from the Nutrition Education for Management of Osteodystrophy trial

AIM

To assess the cost-effectiveness of nutrition education by dedicated dietitians (DD) for hyperphosphatemia management among hemodialysis patients.

MATERIALS AND METHODS

This was a trial-based economic evaluation in 12 Lebanese hospital-based units. In total, 545 prevalent patients were cluster randomized to DD, trained hospital dietitian (THD), and existing practice (EP) groups. During Phase I (6 months), DD (n = 116) received intensive education by DD trained on renal nutrition, THD (n = 299) received care from trained hospital dietitians, and EP (n = 130) received usual care from untrained hospital dietitians. Patients were followed-up during Phase II (6 months).

RESULTS

At baseline, EP had the lowest weekly hemodialysis time, and DD had the highest serum phosphorus and malnutrition-inflammation score. The additional costs of the intervention were low compared with the societal costs (DD: $76.7, $21,007.7; EP: $4.6, $18,675.4; THD: $17.4, $20,078.6, respectively). Between Phases I and II, DD showed the greatest decline in services use and societal costs (DD: -$2,364.0; EP: -$1,727.7; THD: -$1,105.7). At endline, DD experienced the highest decrease in adjusted serum phosphorus (DD: -0.32; EP: +0.16; THD: +0.04 mg/dL), no difference in quality-adjusted life-years (QALY), and the highest societal costs. DD had a cost-effectiveness ratio of $7,853.6 per 1 mg decrease in phosphorus, compared with EP; and was dominated by THD. Regarding QALY, DD was dominated by EP and THD. The results were sensitive to changes in key parameters.

LIMITATIONS

The analysis depended on numerous assumptions. Interpreting the results is limited by the significant baseline differences in key parameters, suggestive of higher baseline societal costs in DD.

CONCLUSIONS

DD yielded the greatest effectiveness and decrease in societal costs, but did not affect QALY. Regarding serum phosphorus, DD was likely to be cost-effective compared with EP, but had a low cost-effectiveness probability compared with THD. Regarding QALY, DD was not likely to be cost-effective. Assessing the long-term cost-effectiveness of DD, on similar groups, is recommended.

Cost-effectiveness of phosphate binders among patients with chronic kidney disease not yet on dialysis: a long way to go

Hyperphosphatemia management is integral to the management of patients with chronic kidney disease. This mineral abnormality is associated with greater costs, but so is its management, especially with the use novel phosphate binders. The economic evaluation of these pharmaceutical agents is increasingly needed to provide evidence for value of money spent and inform resource allocation. Recently, Nguyen et al. explored the economical attractiveness of Sevelamer relative to Calcium Carbonate among patients with chronic kidney disease not yet on dialysis and concluded that the former was cost-effective. The current commentary discusses the results of this analysis and sheds light on the methodological challenges of economic evaluations in this field.