Impact of hemochromatosis screening in patients with indeterminate results: the hemochromatosis and iron overload screening study

Haemochromatosis patients' research priorities: Towards an improved quality of life

BACKGROUND

Chronic diseases are associated with a range of functional and psychosocial consequences that can adversely affect patients' quality of life (QoL). Haemochromatosis (HC) is a genetically heterogeneous disorder characterized by chronic iron overload that can ultimately lead to multiple organ dysfunction. Clinical diagnosis remains challenging due to the nonspecificity of symptoms and a lack of confirmatory genotyping in a substantial proportion of patients. Illness perception among HC patients has not been extensively investigated, lacking relevant information on how to improve their QoL.

METHODS

We present the results of the first worldwide survey conducted in nearly 1500 HC respondents, in which we collected essential demographic information and identified the aspects that concern HC patients the most.

RESULTS

Out of all the participants, 45.3% (n = 676) voiced their concern about physical and psychological consequences such as HC-related arthropathies, which can ultimately affect their social functioning. A similar proportion of patients (n = 635, 42.5%) also consider that better-informed doctors are key for improved HC disease management. Taking a patient-centred approach, we expose differences in patients' disease perspective by social and economic influences.

CONCLUSIONS

We identify potential targets to improve patients' health-related QoL and reflect on strategic measures to foster gender equity in access to health resources. Finally, we make a call for a highly coordinated effort across a range of public policy areas to empower participants in the HC research process and design.

PATIENT OR PUBLIC CONTRIBUTION

Nearly 1500 patients with hereditary HC responded to an anonymized online survey in which research and clinical priorities were addressed regarding this chronic and rare disease.

A new approach to assessing affect and the emotional implications of personal genomic testing for common disease risk

AIMS

Personal genomic testing (PGT) for common disease risk is becoming increasingly frequent, but little is known about people's array of emotional reactions to learning their genomic risk profiles and the psychological harms/benefits of PGT. We conducted a study of post-PGT affect, including positive, neutral, and negative states that may arise after testing.

METHODS

A total of 228 healthy adults received PGT for common disease variants and completed a semistructured research interview within 2 weeks of disclosure. The study participants reported how the PGT results made them feel in their own words. Using an iterative coding process, the responses were organized into three broad affective categories: negative, neutral, and positive affect.

RESULTS

Neutral affect was the most prevalent response (53.9%), followed by positive affect (26.9%) and negative affect (19.2%). We found no differences by gender, race, or education.

CONCLUSIONS

While <20% of participants reported negative affect in response to learning their genomic risk profile for common diseases, a majority experienced either neutral or positive emotions. These findings contribute to the growing evidence that PGT does not impose significant psychological harms. Moreover, they point to a need to better link theories and assessments in both emotional and cognitive processing to capitalize on PGT information for healthy behavior change.

Effect of ambiguous hemochromatosis gene test results on physician utilization

BACKGROUND

Genetic test results may be available to greater numbers of people through genetic screening projects and other means. The effects of widespread genetic testing and notification of genetic test results, particularly added costs through increased physician utilization, have not been clearly established.

METHODS

A primary care-based cohort of 20,306 participants (Hemochromatosis and Iron Overload Study, Ontario site) were tested for the C282Y and H63D mutations of the HFE gene and for abnormal serum ferritin (SF) and transferrin saturation levels. The primary outcome variable was the total number of physician claims per patient after genetic test notification by mail. Multiple Poisson regression was used to adjust for age, sex, baseline SF, diagnoses of arthritis, diabetes, heart failure and impotence, self-rated health, and the number of claims during the 12 months before notification of results. The reference group had no HFE mutations (wild type) and normal transferrin saturation/SF values.

RESULTS

Participants with an ambiguous hemochromatosis gene test and normal iron levels had statistically significantly higher average physician utilization of 3.0%. Participants with HFE mutations (excluding C282Y homozygotes) and elevated iron values showed a 6% increase in physician utilization.

CONCLUSIONS

The health effects, if any, of increased utilization in heterozygotes or those with mild ferritin elevations are unknown but are unlikely to be large at the population level. Ambiguous genetic test results are associated with increased physician service use and should be considered when assessing the complete societal costs of widespread genetic testing.

Points to consider in assessing and appraising predictive genetic tests

The use of predictive genetic tests is expanding rapidly. Given limited health care budgets and few national coverage decisions specifically for genetic tests, evidence of benefits and harms is a key requirement in decision making; however, assessing the benefits and harms of genetic tests raises a number of challenging issues. Frequently, evidence of medical benefits and harms is limited due to practical and ethical limitations of conducting meaningful clinical trials. Also, clinical endpoints frequently do not capture the benefit appropriately because the main purpose of many genetic tests is personal utility of knowing the test results, and costs of the tests and counseling can be insufficient indicators of the total costs of care. This study provides an overview of points to consider for the assessment of benefits and harms from genetic tests in an ethically and economically reflected manner. We discuss whether genetic tests are sufficiently exceptional to warrant exceptional methods for assessment and appraisal.

Impact of gene patents and licensing practices on access to genetic testing for hereditary hemochromatosis

Hereditary hemochromatosis is an iron metabolism disorder that leads to excess iron buildup, especially in the heart, liver, and pancreas. Mutations in the HFE gene are the single most common cause of hereditary hemochromatosis, which can be treated effectively if diagnosed early. Patents cover the HFE gene, related proteins, screening methods, and testing kits. Most initial testing for hereditary hemochromatosis is biochemical, but HFE deoxyribonucleic acid testing or genotyping is used to confirm a diagnosis of inherited hemochromatosis. Concerns over patents covering HFE testing emerged in 2002, when scholars argued that exclusive licensing and the patent-enabled sole provider model then in place led to high prices and limited access. Critics of the sole provider model noted that the test was available at multiple laboratories before the enforcement of patents. By 2007, however, Bio-Rad Limited, acquired the key intellectual property and sublicensed it widely. In part because of broad, nonexclusive licensing, there are now multiple providers and testing technologies, and research continues. This case study illustrates how both changes in intellectual property ownership and evolving clinical utility of HFE genetic testing in the last decade have effected the licensing of patents and availability of genetic testing.

Potential nonresponse bias in a clinical examination after initial screening using iron phenotyping and HFE genotyping in the hemochromatosis and iron overload screening study

BACKGROUND

Little is known about the factors affecting participation in clinical assessments after HEmochromatosis and IRon Overload Screening.

METHODS

Initial screening of 101,168 primary care patients in the HEmochromatosis and IRon Overload Screening study was performed using serum iron measures and hemochromatosis gene (HFE) genotyping. Using iron phenotypes and HFE genotypes, we identified 2256 cases and 1232 controls eligible to participate in a clinical examination. To assess the potential for nonresponse bias, we compared the sociodemographic, health status, and attitudinal characteristics of participants and nonparticipants using adjusted odds ratios (ORs) and 95% confidence interval (CI).

RESULTS

Overall participation was 74% in cases and 52% in controls; in both groups, participation was highest at a health maintenance organization and lowest among those under 45 years of age (cases: OR = 0.68; 95% CI 0.53, 0.87; controls: OR = 0.59; 95% CI 0.44, 0.78). In controls only, participation was also lower among those over 65 years of age than the reference group aged 46-64 (OR = 0.64; 95% CI 0.47, 0.88). Among cases, participation was higher in HFE C282Y homozygotes (OR = 3.98; 95% CI 2.60, 6.09), H63D homozygotes (OR = 2.79; 95% CI 1.23, 6.32), and C282Y/H63D compound heterozygotes (OR = 1.82; 95% CI 1.03, 3.22) than in other genotypes, and lower among non-Caucasians and those who preferred a non-English language than in Caucasians and those who preferred English (p < 0.0001).

CONCLUSIONS

Subjects with greatest risk to have iron overload (C282Y homozygotes; cases > or =45 years; Caucasians) were more likely to participate in a postscreening clinical examination than other subjects. We detected no evidence of strong selection bias.

Psychosocial aspects of DNA testing for hereditary hemochromatosis in at-risk individuals: a systematic review

AIM

To review the psychosocial benefits and harms of DNA testing for HFE-related hereditary hemochromatosis (HH) in at-risk individuals.

BACKGROUND

HH is a common genetic disease in people of European descent. DNA-based predisposition testing is used for diagnosis or in the context of family testing, but there are concerns about potential psychosocial consequences.

METHODS

Fifteen electronic databases (including Medline and Cochrane) were searched from inception to April 2007 to identify any quantitative or qualitative primary research that considered DNA testing of individuals considered at-risk of HH and reported psychosocial outcomes. Inclusion criteria, data extraction, and quality assessment were undertaken by standard methodology.

RESULTS

Three observational studies met the inclusion criteria of the review; each had methodological limitations. On receipt of test results, anxiety levels fell or were unchanged; general health-related quality-of-life outcomes improved in some aspects, or were unchanged with respect to pretest result values. Outcomes were not reported separately for those referred for diagnosis and those with family history of HH. Results suggest that genetic testing for HH in at-risk individuals is accompanied by few negative psychosocial outcomes.

CONCLUSION

The evidence on the psychosocial aspects of DNA testing for HH in at-risk individuals is limited. Further research might be required if other factors influencing the natural history of the disease phenotype are identified.

Hereditary hemochromatosis: insights from the Hemochromatosis and Iron Overload Screening (HEIRS) Study

Hemochromatosis comprises a group of inherited disorders resulting from mutations of genes involved in regulating iron metabolism. The multicenter, multi-ethnic Hemochromatosis and Iron Overload Screening (HEIRS) Study screened approximately 100,000 participants in the US and Canada, testing for HFE mutations, serum ferritin and transferrin saturation. As in other studies, HFE C282Y homozygosity was common in Caucasians but rare in other ethnic groups, and there was a marked heterogeneity of disease expression in C282Y homozygotes. Nevertheless, this genotype was often associated with elevations of serum ferritin and transferrin saturation and with iron stores of more than four grams in men but not in women. If liver biopsy was performed, in some cases because of evidence of hepatic dysfunction, fibrosis or cirrhosis was often found. Combined elevations of serum ferritin and transferrin saturation were observed in non-C282Y homozygotes of all ethnic groups, most prominently Asians, but not often with iron stores of more than four grams. Future studies to discover modifier genes that affect phenotypic expression in C282Y hemochromatosis should help identify patients who are at greatest risk of developing iron overload and who may benefit from continued monitoring of iron status to detect progressive iron loading.

A decision analysis model for diagnostic strategies using DNA testing for hereditary haemochromatosis in at risk populations

BACKGROUND

New techniques for diagnosing hereditary haemochromatosis (HHC) have become available alongside traditional tests such as liver biopsy and serum iron studies.

AIM

To evaluate DNA tests in people suspected of having haemochromatosis at clinical presentation compared to liver biopsy, and in family members of those diagnosed with haemochromatosis compared to phenotypic iron studies in UK.

METHODS

Decision analytic models were constructed to compare the costs and consequences of the diagnostic strategies for a hypothetical cohort of people with suspected haemochromatosis. For each strategy, the number of cases of haemochromatosis identified and treated and the resources used were estimated.

RESULTS

For diagnostic strategies in people suspected clinically of having haemochromatosis, the DNA strategy is cost saving compared to liver biopsy (cost saved per case detected, 123 pounds) and continues to be so across all ranges of parameters. For family testing, the DNA strategy is cost saving for the offspring of the proband but not for siblings. If the DNA test cost were to reduce by 40% to 60 pounds or, if in the phenotypic model, those with initially normal iron indices were retested twice instead of once, the DNA strategy would be the cheaper one.

CONCLUSION

Diagnostic strategies involving DNA testing are likely to be cost saving in clinical cases with iron overload and in the offspring of index cases. This study supports the UK guideline recommendations for the use of DNA testing in UK.

Health-related quality of life in a racially diverse population screened for hemochromatosis: results from the Hemochromatosis and Iron Overload Screening (HEIRS) study

PURPOSE

The HEIRS Study screened 101,168 primary care participants for iron overload with serum transferrin saturation (TS), serum ferritin (SF), and C282Y and H63D mutations of the HFE gene. The objective of this study was to evaluate the impact of screening on participants' well-being.

METHODS

All C282Y homozygotes, participants with an elevated TS and SF concentration, and a control group of phenotype-genotype negative persons, with neither C282Y nor H63D mutations in the HFE gene were recalled for a clinical evaluation. Health-related quality of life was assessed before screening and approximately 1 week after receipt of the results. Health worries were assessed only at follow-up.

RESULTS

Participants (N = 1478) completed both initial and follow-up surveys. After adjusting for model covariates, phenotype and genotype combinations were statistically significant predictors of changes in psychological well-being (P = 0.0001) and general health (P = 0.0014). C282Y homozygotes with transient elevations in TS or SF were significantly more likely to worry about their health compared to study controls. Race, ethnicity, and preferred language subgroups differed on psychological well-being, general health, and health worry.

CONCLUSION

Iron phenotype and HFE genotype are associated with health-related quality of life. Health worry was greatest among those considered genetically "at risk. " This may have important implications for multi-ethnic population-based screening studies in which genotype and phenotype are communicated.

Results communication and patient education after screening for possible hemochromatosis and iron overload: experience from the HEIRS Study of a large ethnically and linguistically diverse group

PURPOSE

We assessed the effectiveness of educational interventions for conveying clinical findings and information about hereditary hemochromatosis (HH) and iron overload (IO) to individuals evaluated clinically after initial screening for HH/IO with serum ferritin (SF) concentration, transferrin saturation (TS), and HFE genotyping.

METHODS

A questionnaire mailed to 2300 cases and controls 1 month after a letter summarizing clinical findings measured understanding of results and recommendations, knowledge of HH/IO, and satisfaction with information received.

RESULTS

Of 1622 (70.5%) participants completing relevant items, 83.6% were satisfied with receiving initial screening results by mail, 93.4% found information clear and easy to understand, 89.2% generally felt they got enough information, but 47.5% still had questions. C282Y/C282Y homozygosity with normal TS/SF predicted the best understanding of genetic results. Many with no mutations thought relatives were at risk. Iron levels created most confusion, and a third incorrectly recalled treatment recommendations. Having any abnormal result, lower education, older age, and being non-white, and/or non-English speaking predicted lower understanding.

CONCLUSIONS

Combining genotypic and phenotypic screening for HH/IO creates additional difficulties in communicating results-particularly to those with low health literacy. Explaining aberrant iron TS and SF levels and low-risk genotypes, follow-up recommendations, and risk to relatives will need creative, culturally appropriate strategies.