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Cost-effectiveness of a family and DNA based screening programme on familial hypercholesterolaemia in The Netherlands |
Marang-van de Mheen P J, ten Asbroek A H, Bonneux L, Bonsel G J, Klazinga N S |
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Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. CRD summary This study examined the cost-effectiveness of familial hypercholesterolaemia screening in relatives of diagnosed patients, based on the implementation of a screening programme in The Netherlands between 1994 and 1997. The cost-effectiveness of the screening, regardless of the subsequent treatment strategy, was within the range that required explicit political consideration and the price of the statin therapy was the most important factor in determining the costs. The study had some methodological limitations and the authors’ conclusions should be treated with caution. Type of economic evaluation Cost-effectiveness analysis Study objective This study examined the cost-effectiveness of a screening programme on heterozygous familial hypercholesterolaemia (FH) in relatives of patients diagnosed with FH. The screening programme was implemented in The Netherlands between 1994 and 1997. Interventions The screening, at lipid research clinics, targeted first- and second-degree relatives of the first family member to be diagnosed (proband) with FH and a low density lipoprotein (LDL) receptor gene mutation. Various treatment strategies, following screening, were compared with no screening:
Strategy one: all individuals with a mutation for FH were eligible for treatment; Strategy two: all individuals with a mutation for FH and a cholesterol level above the 95th percentile of the general population were eligible for treatment; Strategy three: all individuals with a mutation for FH and who fulfilled the treatment criteria in the national CBO (Dutch Institute on Health Care Improvement) consensus guideline on hypercholesterolaemia were eligible for treatment; Strategy four: all individuals with a mutation for FH, who were not treated when screened, were eligible for treatment; Strategy five: the same as Strategy two, but only those who were not treated at screening; and Strategy six: the same as strategy three, but only those who were not treated at screening.
The treatment was based on statins (50% atorvastatin, 45% simvastatin, and 5% pravastatin). Location/setting Netherlands/secondary care. Methods Analytical approach:This economic evaluation was based on a specific disease model with a lifetime horizon. The authors did not explicitly state the perspective adopted.
Effectiveness data:The clinical evidence was derived from a registry of 2,229 screened relatives of patients with FH, from 1994 to 1997. This source provided data on the incidence of hypercholesterolaemia and the screening accuracy. These data were combined with the Framingham risk function to calculate the expected lifetime risk of coronary heart disease (CHD) and survival for patients eligible for screening. Further data for the cumulative survival were derived from published studies. The key clinical input was the risk of CHD for patients with hypercholesterolaemia.
Monetary benefit and utility valuations:Not relevant.
Measure of benefit:Life-years (LYs) were used as the summary benefit measure.
Cost data:The economic analysis included two main categories of costs: those associated with the screening process; and those associated with the follow-up process, including the direct medical costs and the indirect medical costs during life years gained due to treatment. The former category included the deoxyribonucleic acid (DNA) test in FH probands to find the mutation for the family screening, the programme costs of the family screening, and the DNA tests for the family members. The latter category included the general practitioner consultation, consultations at a lipid research clinic, measurement of the lipid profile, and treatment with cholesterol lowering drugs. The resource consumption appears to have been based on authors’ assumptions or observed frequencies. The unit costs and quantities of resources used were presented separately per year of treatment. National tariffs were used to reflect the actual costs. The cost data were gathered between 1994 and 1998, but 1998 prices were used and all costs were in Euros (EUR).
Analysis of uncertainty:A deterministic sensitivity analysis was undertaken to investigate the assumptions on family history, Framingham based CHD survival estimates, and efficacy of cholesterol lowering drugs. Results In the study cohort, the additional cost of screening over no screening ranged from EUR 5,637,424 with strategy six to EUR 27,048,563 with strategy one. Medication costs were the main cost category in all cases.
The LYs gained ranged from 204 with strategy six to 865 with strategy one.
The incremental cost-effectiveness ratio compared with no screening ranged from EUR 25,613 with strategy three to EUR 32,164 with strategy four.
The addition of cholesterol level measurement to the screening programme resulted in similar cost-effectiveness ratios.
The results of the sensitivity analysis indicated that an assumed 20% higher blood pressure in the screened population or an assumed higher efficacy of cholesterol lowering drugs resulted in a more favourable cost-effectiveness ratio. Authors' conclusions The authors concluded that the cost-effectiveness of the FH screening, regardless of the subsequent treatment strategy, was within the range that required explicit political consideration in The Netherlands. The price of the statin therapy was the most important factor in determining the costs. CRD commentary Interventions:The selection of comparators was appropriate, not only because screening was compared with no screening, but also because the authors covered all possible subsequent treatment strategies.
Effectiveness/benefits:The clinical data were derived from a cohort study that reflected the implementation of the screening programme in the authors’ setting. A relatively large sample of patients was enrolled, but little information on their characteristics and those of the study was provided. Similarly, the key features of the other published sources of data were not reported. This limits the possibility of making an objective assessment of the validity of these clinical estimates. The derivation of the benefit measure was based on the key clinical assumptions. LYs are a validated benefit measure, which capture the impact of the screening and treatment on patients’ health, and which are comparable with the benefits of other health care interventions. The authors noted that the Framingham function has been shown to be applicable to European patients, but its use in younger and older ages may result in bias. Another potential limitation of the analysis was that perfect compliance with screening and treatment was assumed.
Costs:The authors did not explicitly state the economic viewpoint of their study and it cannot be readily identified from the information provided in the paper. A breakdown of the cost items was provided and some data on the unit costs and resource quantities was given, but these data referred to a year of treatment. The price year and the period during which costs and quantities were gathered were reported. The sources of data reflected Dutch official tariffs, but no statistical analyses of the costs were carried out. The approach used to overcome the issue of missing economic data was described, and was based on authors’ assumptions.
Analysis and results:The costs and benefits were extensively reported for all screening and treatment strategies, but were presented only in incremental terms of screening versus no screening. The issue of uncertainty was investigated only with respect to the key clinical assumptions. Both the clinical and economic data reflected the Dutch setting and the findings may not be transferable to other settings or other patient populations. The authors justified the lack of discounting for both costs and benefits on the basis of a similar flow in future time, but discounting could still have been relevant given the length of the time horizon.
Concluding remarks:The study had some methodological limitations and the authors’ conclusions should be treated with caution. Bibliographic details Marang-van de Mheen P J, ten Asbroek A H, Bonneux L, Bonsel G J, Klazinga N S. Cost-effectiveness of a family and DNA based screening programme on familial hypercholesterolaemia in The Netherlands. European Heart Journal 2002; 23(24): 1922-1930 Other publications of related interest Goldman L, Goldman PA, Williams LW, et al. Cost effectiveness considerations in the treatment of heterozygous familial hypercholesterolemia with medications. Am J Cardiol 1993;72:75D-9D.
Pharoah PD, Hollingworth W. Cost effectiveness of lowering cholesterol concentration with statins in patients with and without pre-existing coronary heart disease: life table method applied to health authority population. BMJ 1996;312:1443-8.
Krumholz HM, Seeman TE, Merrill SS, et al. Lack of association between cholesterol and coronary heart disease mortality and morbidity and all-cause mortality in persons older than 70 years. JAMA 1994;272:1335-40. Indexing Status Subject indexing assigned by NLM MeSH Adolescent; Adult; Aged; Child; Child, Preschool; Cohort Studies; Coronary Disease /diagnosis /economics /genetics; Cost-Benefit Analysis; Genetic Testing /economics; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors /therapeutic use; Hyperlipoproteinemia Type II /diagnosis /economics /genetics; Infant; Infant, Newborn; Middle Aged; Netherlands; Program Evaluation; Risk Factors; Sensitivity and Specificity AccessionNumber 22003000103 Date bibliographic record published 30/01/2003 Date abstract record published 05/08/2009 |
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