A Systematic Review and Narrative Synthesis of Health Economic Studies Conducted for Hereditary Haemochromatosis

Population Screening for Hereditary Haemochromatosis-Should It Be Carried Out, and If So, How?

The Human Genome Project, completed in 2003, heralded a new era in precision medicine. Somewhat tempering the excitement of the elucidation of the human genome is the emerging recognition that there are fewer single gene disorders than first anticipated, with most diseases predicted to be polygenic or at least gene-environment modified. Hereditary haemochromatosis (HH) is an inherited iron overload disorder, for which the vast majority of affected individuals (>90%) have homozygosity for a single pathogenic variant in the HFE gene, resulting in p.Cys282Tyr. Further, there is significant benefit to an individual in identifying the genetic risk of HH, since the condition evolves over decades, and the opportunity to intervene and prevent disease is both simple and highly effective through regular venesection. Add to that the immediate benefit to society of an increased pool of ready blood donors (blood obtained from HH venesections can generally be used for donation), and the case for population screening to identify those genetically at risk for HH becomes more cogent. Concerns about genetic discrimination, creating a cohort of "worried well", antipathy to acting on medical advice to undertake preventive venesection or simply not understanding the genetic risk of the condition adequately have all been allayed by a number of investigations. So why then has HH population genetic screening not been routinely implemented anywhere in the world? The answer is complex, but in this article we explore the pros and cons of screening for HH and the different views regarding whether it should be phenotypic (screening for iron overload by serum ferritin and/or transferrin saturation) or genotypic (testing for HFE p.Cys282Tyr). We argue that now is the time to give this poster child for population genetic screening the due consideration required to benefit the millions of individuals at risk of HFE-related iron overload.

The Genetic Diagnostics of Hemochromatosis: Disparities in Low- Versus High-Income Countries

This study provides a comprehensive overview of hereditary hemochromatosis (HH), a genetic condition characterized by iron overload due to excessive iron absorption. It elucidates diverse inheritance patterns and clinical manifestations by exploring mutations in critical genes such as HFE (hemochromatosis), HJV (hemojuvelin), HAMP (hepcidin antimicrobial peptide), TfR2 (transferrin receptor 2), and FP (ferroportin). The significance of early screening, diagnosis, and personalized management strategies based on genetic classification is emphasized, particularly in terms of high-income vs. low-income countries. Addressing challenges in diagnosis, genetic testing accessibility, and healthcare disparities, the study highlights the importance of early detection, cost-effective screening strategies, and enhancing healthcare outcomes globally. Advanced genetic testing in high-income countries facilitates early diagnosis and management, reducing complications such as liver disease and cardiomyopathy. In contrast, low-income populations face several barriers, including limited access to genetic testing, high costs, and inadequate healthcare infrastructure. Cost-effective serum ferritin (SF) and transferrin saturation (TS) tests and emerging point-of-care (POC) tests offer affordable diagnostic options for low-resource settings. Additionally, the ongoing development of hepcidin measurement methods holds promise for enhancing diagnostic capabilities. Implementing these strategies can aid healthcare providers in improving global HH management and reducing the burden of iron overload complications. Furthermore, the study underscores the need for public health initiatives to raise awareness about HH, promote routine screenings, and advocate for equitable healthcare policies. Collaborative efforts between governments, healthcare organizations, and research institutions are crucial in addressing the global burden of HH. By fostering international cooperation and resource-sharing, it is possible to bridge the gap between high-income and low-income countries, ensuring all individuals have access to the necessary diagnostic and treatment options. This holistic approach can ultimately lead to better health outcomes and improved quality of life for individuals affected by HH worldwide. This comprehensive examination of HH not only illuminates the genetic and clinical aspects of the condition but also provides a roadmap for addressing the multifaceted challenges associated with its diagnosis and management.

Health Economic Evaluations of Hemochromatosis Screening and Treatment: A Systematic Review

BACKGROUND

Hereditary hemochromatosis (HH) is an autosomal recessive disorder that leads to iron overload and multiorgan failure.

OBJECTIVES

The aim of this systematic review was to provide up-to-date evidence of all the current data on the costs and cost effectiveness of screening and treatment for HH.

METHODS

We searched PubMed, Cochrane Library, National Health Service Economic Evaluation Database (NHSEED), Cost-Effectiveness Analysis Registry (CEA Registry), Health Technology Assessment Database (HTAD), Centre for Reviews and Dissemination (CRD), and Econlit until April 2023 with no date restrictions. Articles that reported cost-utility, cost-description, cost-minimization, cost-effectiveness, or cost-benefit analyses for any kind of management (drugs, screening, etc.) were included in the study. Patients with HH, their siblings, or individuals suspected of having HH were included in the study. All screening and treatment strategies were included. Two authors assessed the quality of evidence related to screening (either phenotype or genotype screening) and treatment (phlebotomy and electrophoresis). Narrative synthesis was used to analyse the similarities and differences between the respective studies.

RESULTS

Thirty-nine papers were included in this study. The majority of the studies reported both the cost of phenotype screening, including transferrin saturation (TS), serum ferritin, and liver biopsy, and the cost of genotype screening (HFE screening, C282Y mutation). Few studies reported the cost for phlebotomy and erythrocytapheresis treatment. Data revealed that either phenotype or genotype screening were cost effective compared with no screening. Treatment studies concluded that erythrocytapheresis might be a cost-effective therapy compared with phlebotomy.

CONCLUSIONS

Economic studies on either the screening, or treatment strategy for HH patients should be performed in more countries. We suggest that cost-effectiveness studies on the role of deferasirox in HH should be carried out as an alternative therapy to phlebotomy.

Twenty-Five Years of Contemplating Genotype-Based Hereditary Hemochromatosis Population Screening

Hereditary hemochromatosis (HH) is a rather frequent, preventable disease because the progressive iron overload affecting many organs can be effectively reduced by phlebotomy. Even before the discovery of the major gene, HFE, in 1996, hemochromatosis was seen as a candidate for population-wide screening programmes. A US Centers of Disease Control and the National Human Genome Research Institute expert panel convened in 1997 to consider genotype-based HH population-wide screening and decided that the scientific evidence available at that time was insufficient and advised against. In spite of a large number of studies performed within the last 25 years, addressing all aspects of HH natural history, health economics, and social acceptability, no professional body worldwide has reverted this decision, and HH remains a life-threatening condition that often goes undetected at a curable stage.

Systematic Review of the Evolution of Health-Economic Evaluation Models of Osteoarthritis

OBJECTIVE

To comprehensively synthesize the evolution of health-economic evaluation models (HEEMs) of all osteoarthritis (OA) interventions, including preventions, core treatments, adjunct nonpharmacologic interventions, pharmacologic interventions, and surgical treatments.

METHODS

The literature was searched within health-economic/biomedical databases. Data extracted included OA type, population characteristics, model setting/type/events, study perspective, and comparators; the reporting quality of the studies was also assessed. The review protocol was registered at the International Prospective Register of Systematic Reviews (CRD42018092937).

RESULTS

Eighty-eight studies were included. Pharmacologic and surgical interventions were the focus in 51% and 44% of studies, respectively. Twenty-four studies adopted a societal perspective (with increasing popularity after 2013), but most (63%) did not include indirect costs. Quality-adjusted life years was the most popular outcome measure since 2008. Markov models were used by 62% of studies, with increasing popularity since 2008. Until 2010, most studies used short-to-medium time horizons; subsequently, a lifetime horizon became popular. A total of 86% of studies reported discount rates (predominantly between 3% and 5%). Studies published after 2002 had a better coverage of OA-related adverse events (AEs). Reporting quality significantly improved after 2001.

CONCLUSION

OA HEEMs have evolved and improved substantially over time, with the focus shifting from short-to-medium-term pharmacologic decision-tree models to surgical-focused lifetime Markov models. Indirect costs of OA are frequently not considered, despite using a societal perspective. There was a lack of reporting sensitivity of model outcome to input parameters, including discount rate, OA definition, and population parameters. While the coverage of OA-related AEs has improved over time, it is still not comprehensive.

Health Care Utilization and Economic Burdens of Hemochromatosis in the United States: A Population-Based Claims Study

BACKGROUND

Little is known about the health care burden of hemochromatosis in the United States, despite its increased morbidity and mortality due to associated advanced liver diseases.

OBJECTIVE

To evaluate the health care utilization and economic burdens of hemochromatosis in the United States using real-world claims data.

METHODS

We performed a case-control analysis of adult participants in the Truven Health MarketScan Commercial Claims database from 2010 to 2015. 37,092 hemochromatosis cases were matched 1:1 by demographics and comorbidities to hemochromatosis-free controls with chronic liver disease using propensity scores. Total and service-specific health care parameters were quantified for the 12 months following versus the 12 months before the first date of hemochromatosis diagnosis and over the 12 months following a randomly selected date for controls. Incremental differences in health care burdens between cases and controls were examined using Wilcoxon signed rank tests and McNemar tests for continuous and dichotomous measures, respectively. Adjusted multivariable regression analyses using generalized linear models were used to compare the health care burdens for cases with controls.

RESULTS

In comparison with the year before, the 12 months following first hemochromatosis diagnoses had a higher total number of claims per patient (34.37 vs. 29.99; P < 0.0001) and an increase in the per-patient total health care costs ($20,023 vs. $16,905; P < 0.0001). After hemochromatosis diagnosis, health care costs were 2%, 8%, 23%, and 43% higher for inpatient admissions, emergency department visits, outpatient visits, and pharmaceutical prescriptions, compared respectively with the 12 months before diagnosis. In the 12 months following the index date, hemochromatosis cases incurred $2,732 more in total unadjusted costs compared with controls. Compared with controls, cases had adjusted incident rate ratio (IRR) 1.26 (95% CI = 1.30-1.77) times the total number of claims (IRR = 1.40, 95% CI = 1.38-1.43) more outpatient visits and IRR = 1.10 (95% CI = 1.08-1.11) excess pharmaceutical claims. Compared with controls, cases had significantly higher adjusted mean health care costs for inpatient services ($6,484 vs. $7,854), outpatient services ($7,032 vs. $11,005), and pharmaceutical claims ($2,520 vs. $2,822; all P values < 0.05). The annual health care costs among type 2 diabetes, hypertension, arthritis, and chronic kidney disease (CKD) patients with hemochromatosis were $6,968, $7,424, $2,967, and $43,847, respectively, higher than type 2 diabetes, hypertension, arthritis, and CKD patients without hemochromatosis (P < 0.0001).

CONCLUSIONS

Hemochromatosis in the United States is associated with significant health care utilization and economic burdens driven by outpatient visits, pharmaceutical claims, and a high number of comorbidities DISCLOSURES: No outside funding supported this study. The authors have no relevant financial or other relationships to disclose. An abstract containing some of the results from this study was accepted for the American Association for the Study of Liver Diseases Meeting; November 9-13, 2018; San Francisco, CA.

Reduction of body iron in HFE-related haemochromatosis and moderate iron overload (Mi-Iron): a multicentre, participant-blinded, randomised controlled trial

BACKGROUND

The iron overload disorder hereditary haemochromatosis is most commonly caused by HFE p.Cys282Tyr homozygosity. In the absence of results from any randomised trials, current evidence is insufficient to determine whether individuals with hereditary haemochromatosis and moderately elevated serum ferritin, should undergo iron reduction treatment. This trial aimed to establish whether serum ferritin normalisation in this population improved symptoms and surrogate biomarkers.

METHODS

This study was a multicentre, participant-blinded, randomised controlled trial done at three centres in Australia. We enrolled people who were homozygous for HFE p.Cys282Tyr, aged between 18 and 70 years, with moderately elevated serum ferritin, defined as 300-1000 μg/L, and raised transferrin saturation. Participants were randomly assigned, via a computer-generated random number, to undergo either iron reduction by erythrocytapheresis (treatment group) or sham treatment by plasmapheresis (control group). Randomisation was stratified by baseline serum ferritin (<600 μg/L or ≥600 μg/L), sex, and study site. Erythrocytapheresis and plasmapheresis were done every 3 weeks, the number of procedures and volume of red cells or plasma removed determined on the basis of each patient's haemoglobin, haematocrit, and serum ferritin concentration, as well their height and weight. In the erythrocytapheresis group, the target was to reduce serum ferritin to less than 300 μg/L. The number of procedures for the control group was based on the initial serum ferritin and prediction of decrease in serum ferritin of approximately 120 μg/L per treatment. The primary outcome was patient-reported Modified Fatigue Impact Scale (MFIS) score, measured at baseline and before unblinding. Analyses were by intention to treat, including the safety analysis. The trial is registered with ClinicalTrials.gov, number NCT01631708, and has been completed.

FINDINGS

Between Aug 15, 2012, and June 9, 2016, 104 participants were randomly assigned to the treatment (n=54) and control (n=50) groups, of whom 94 completed the study (50 in the treatment group and 44 in the control group). Improvement in MFIS score was greater in the treatment group than in the control group (mean difference -6·3, 95% CI -11·1 to -1·4, p=0·013). There was a significant difference in the cognitive subcomponent (-3·6, -5·9 to -1·3, p=0·0030), but not in the physical (-1·90 -4·5 to 0·63, p=0·14) and psychosocial (-0·54, -1·2 to 0·11, p=0·10) subcomponents. No serious adverse events occurred in either group. One participant in the control group had a vasovagal event and 17 participants (14 in the treatment group and three in the control group) had transient symptoms assessed as related to hypovolaemia. Mild citrate reactions were more common in the treatment group (32 events [25%] in 129 procedures) compared with the control group (one event [1%] in 93 procedures).

INTERPRETATION

To our knowledge, this study is the first to objectively assess the consequences of iron removal in individuals with hereditary haemochromatosis and moderately elevated serum ferritin. Our results suggest that serum ferritin normalisation by iron depletion could be of benefit for all individuals with hereditary haemochromatosis and elevated serum ferritin levels.

FUNDING

National Health and Medical Research Council (Australia).

Cost-Effectiveness of Different Population Screening Strategies for Hereditary Haemochromatosis in Australia

INTRODUCTION

Amongst populations of northern European ancestry, HFE-associated haemochromatosis is a common genetic disorder characterised by iron overload. In the absence of treatment, excess iron is stored in parenchymal tissues, causing morbidity and mortality. Population screening programmes may increase early diagnosis and reduce associated disease. No contemporary health economic evaluation has been published for Australia. The objective of this study was to identify cost-effective screening strategies for haemochromatosis in the Australian setting.

METHODS

A Markov model using probabilistic decision analysis was developed comparing four adult screening strategies: the status quo (cascade and incidental screening), genotyping with blood and buccal samples and transferrin saturation followed by genotyping (TfS). Target populations were males (30 years) and females (45 years) of northern European ancestry. Cost-effectiveness was estimated from the government perspective over a lifetime horizon.

RESULTS

All strategies for males were cost-effective compared to the status quo. The incremental costs (standard deviation) associated with genotyping (blood) were AUD7 (56), TfS AUD15 (45) and genotyping (buccal) AUD63 (56), producing ICERs of AUD1673, 4103 and 15,233/quality-adjusted life-year (QALY) gained, respectively. For females, only the TfS strategy was cost-effective, producing an ICER of AUD10,195/QALY gained. Approximately 3% of C282Y homozygotes were estimated to be identified with the status quo approach, compared with 40% with the proposed screening strategies.

CONCLUSION

This model estimated that genotyping and TfS strategies are likely to be more cost-effective screening strategies than the status quo.

Interventions for hereditary haemochromatosis: an attempted network meta-analysis

BACKGROUND

Hereditary haemochromatosis is a genetic disorder related to proteins involved in iron transport, resulting in iron load and deposition of iron in various tissues of the body. This iron overload leads to complications including liver cirrhosis (and related complications such as liver failure and hepatocellular carcinoma), cardiac failure, cardiac arrhythmias, impotence, diabetes, arthritis, and skin pigmentation. Phlebotomy (venesection or 'blood letting') is the currently recommended treatment for hereditary haemochromatosis. The optimal treatment of hereditary haemochromatosis remains controversial.

OBJECTIVES

To assess the comparative benefits and harms of different interventions in the treatment of hereditary haemochromatosis through a network meta-analysis and to generate rankings of the available treatments according to their safety and efficacy. However, we found only one comparison. Therefore, we did not perform the network meta-analysis and we assessed the comparative benefits and harms of different interventions using standard Cochrane methodology.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and randomised clinical trials registers to March 2016 to identify randomised clinical trials on treatments for hereditary haemochromatosis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in participants with hereditary haemochromatosis. We excluded trials which included participants who had previously undergone liver transplantation. We considered any of the various interventions compared with each other or with inactive treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the odds ratio (OR) and rate ratio with 95% confidence intervals (CI) using both fixed-effect and random-effects models with RevMan 5 based on available-participant analysis. We assessed risk of bias according to Cochrane, controlled risk of random errors with Trial Sequential Analysis, and assessed the quality of the evidence using GRADE.

MAIN RESULTS

Three trials with 146 participants met the inclusion criteria of this review. Two parallel group trials with 100 participants provided information on one or more outcomes. The remaining trial was a cross-over trial, with no usable data for analysis. All the trials were at high risk of bias. Overall, all the evidence was of very low quality. All three trials compared erythrocytapheresis (removal of red cells only, instead of whole blood) versus phlebotomy. Two of the trials shared the same first author. The mean or median age in the three trials ranged from 42 to 55 years. None of the trials reported whether the included participants were symptomatic or asymptomatic or a mixture of both. Two trials were conducted in people who were haemochromatosis treatment-naive. The trial that provided most data for this review excluded people with malignancy, heart failure, and serious cardiac arrhythmias. We found no trials assessing iron-chelating agents.Only one of the trials with 38 participants reported no short-term mortality and no serious adverse events at the end of the short-term follow-up (eight months). Two trials reported the proportion of people with adverse events: 10/49 (20.4%) in the erythrocytapheresis group versus 11/51 (21.6%) in the phlebotomy group. One of these two trials provided data on adverse event rates (42.1 events per 100 participants with erythrocytapheresis versus 52.6 events per 100 participants with phlebotomy). There was no evidence of differences in the proportion of people with adverse events and the number of adverse events (serious and non-serious) between the groups (proportion of people with adverse events: OR 0.93, 95% CI 0.36 to 2.43; participants = 100; trials = 2; number of adverse events: rate ratio 0.80, 95% CI 0.32 to 2.03; participants = 38; trial = 1). There was no difference between the groups regarding short-term health-related quality of life (mean difference (MD) 1.00, 95% CI -10.80 to 12.80; participants = 38; trials = 1). This outcome was measured using EQ-VAS (range: 0 to 100 where a higher score indicates better health-related quality of life). None of the trials reported mortality beyond one year, health-related quality of life beyond one year, liver transplantation, decompensated liver disease, cirrhosis, hepatocellular carcinoma, diabetes, or cardiovascular complications during the long-term follow-up.The two trials that provided data for this review were funded by parties with no vested interest in the results; the source of funding of the third trial was not reported.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine whether erythrocytapheresis is beneficial or harmful compared with phlebotomy. Phlebotomy has less equipment requirements and remains the treatment of choice in people with hereditary haemochromatosis who require blood letting in some form. However, it should be noted that there is no evidence from randomised clinical trials that blood letting in any form is beneficial in people with hereditary haemochromatosis. Having said this, a trial including no treatment is unlikely to be conducted. Future trials should compare different frequencies of phlebotomy and erythrocytapheresis versus phlebotomy with and without different iron-chelating agents compared with each other, and with placebo. Such trials should include long-term follow-up of participants (e.g. using national record linkage databases) to determine whether treatments are beneficial or harmful in terms of clinical outcomes such as deaths, health-related quality of life, liver damage and its consequences, heart damage and its consequences, and other outcomes that are of importance to people with hereditary haemochromatosis.

Quality of life utility values for hereditary haemochromatosis in Australia

Background

Hereditary hemochromatosis (HH) is a common autosomal recessive disorder amongst persons of northern European heritage. If untreated, iron accumulates in parenchymal tissues causing morbidity and mortality. As diagnosis often follows irreversible organ damage, screening programs have been suggested to increase early diagnosis. A lack of economic evidence has been cited as a barrier to establishing such a program. Previous analyses used poorly estimated utility values. This study sought to measure utilities directly from people with HH in Australia.

Methods

Volunteers with HH were recruited to complete a web-based survey. Utility was assessed using the Assessment of Quality of Life 4D (AQOL-4D) instrument. Severity of HH was graded into four categories. Multivariable regression analysis was performed to identify parameters associated with HSUV.

Results

Between November 2013 and November 2014, 221 people completed the survey. Increasing severity of HH was negatively associated with utility. Mean (standard deviation) utilities were 0.76 (0.21), 0.81 (0.18), 0.60 (0.27), and 0.50 (0.27) for categories 1–4 HH respectively. Lower mean utility was found for symptomatic participants (categories 3 and 4) compared with asymptomatic participants (0.583 v. 0.796). Self-reported HH-related symptoms were negatively associated with HSUV (r = −0.685).

Conclusions

Symptomatic stages of HH and presence of multiple self-reported symptoms were associated with decreasing utility. Previous economic analyses have used higher utilities which likely resulted in underestimates of the cost effectiveness of HH interventions. The utilities reported in this paper are the most robust available, and will contribute to improving the validity of future economic models for HH.