Cost-effectiveness analysis of prenatal population-based fragile X carrier screening

To investigate the differences in outcomes and costs from utilizing widespread prenatal population-based fragile X carrier screening. A decision tree was designed comparing screening versus not screening for the fragile X FMR1 permutation in all pregnant women. Baseline values included 4,000,000 pregnancies per year, prevalence of 61-200 CGG repeat permutations of 3.1 per 1000, expansion of these permutations of 8.9%, and a 99% sensitivity of a PCR screening test. We varied the cost of the screening test from $150 to $310 (a test that includes both PCR and Southern blotting) and the number of children per woman from 1 to 3. Outcomes included societal costs of the screening regimen, numbers of procedure-related losses, fragile X fetuses identified, and a cost per quality adjusted life-year (QALY) ratio. A sensitivity analysis of the probabilities, utilities, and costs was performed. The screening strategy would lead to the identification of 98% of the over 1100 fragile X–affected fetuses annually. 1.97 fragile X fetuses would be identified for each procedure-related loss caused by amniocentesis. Assuming the cost of $150 and only one child, the cost per QALY was $48,361, or marginally cost-effective. In the sensitivity analysis (see Table) the screening strategy became cost saving with a $150 test and 2 children per woman, or for 3 children per woman. Population-based screening for the fragile X permutation may be both clinically desirable and cost-effective. Further clarification of this issue would be achieved via prospective pilot studies of this screening modality in the prenatal setting.Tabled 1Sensitivity analysis of CEA for fragile X carrier screeningCost of Screening Test1 Child (Cost/QALY)2 children (Cost/QALY)3 children (Cost/QALY)$150$48,362−$33,839−$61,787$310$223,723$53,842−$9,918 Open table in a new tab