Screening blood donors for hereditary hemochromatosis: decision analysis model comparing genotyping to phenotyping.

OBJECTIVE: The identification of a gene for hereditary hemochromatosis in 69-100% of typical hemochromatosis patients has resulted in a genotypic test to identify persons with the typical missense mutation. Population screening by genotyping has the potential to reduce screening costs because of a high specificity of the genetic test.
METHODS: Decision analysis techniques are used to compare the outcome, utility, and incremental cost savings of a plan to screen voluntary blood donors and their siblings for hemochromatosis using a genotypic test (C282Y mutation) with phenotypic tests (transferrin saturation, serum ferritin).
RESULTS: Genotypic screening is less expensive than phenotypic screening only if the cost of the initial genetic test is less than $20. The screening program saves money (dominant strategy) if the cost of the initial genetic test is less than $28. Incremental cost saving declines as the cost of the gene test increases. At a gene test cost of $173, it costs $109,358 to identify a homozygote with potential life-threatening illness. Incremental cost saving also declines as the penetrance of the hemochromatosis gene in the population screened decreases. Phenotypic screening with confirmatory genetic testing results in a cost of $2,711 per homozygote with life-threatening complications.
CONCLUSIONS: Population screening programs for hemochromatosis have the potential to save money. Optimal strategies for screening include initial testing for iron overload (phenotyping) with confirmatory genetic testing, or initial genetic testing if the test is less than $28.