A public health screening program for Down syndrome in Quebec, Canada, found that cell-free DNA noninvasive prenatal testing (NIPT) could be implemented at the same cost as the current screening program, according to computer simulations.
The budget impact analysis in the journal Cost Effectiveness and Resource Allocation noted that although NIPT using cell-free fetal DNA in maternal plasma is a highly accurate test for prenatal screening for Down syndrome and has been reported to be cost-effective when used as a contingent test, evidence is lacking about its budget impact.
The current screening program is a serum integrated screening approach, which integrates biological measurements performed at two periods of pregnancy: first trimester pregnancy-associated plasma protein A (PAPP-A) and second trimester quad markers in two separate blood tests.
Contingent NIPT comprises SIPS and NIPT.
The Canadian investigators simulated the budget impact of implementing Contingent NIPT into the current Quebec Trisomy 21 public Prenatal Screening, Serum Integrated prenatal screening (SIPS) via a virtual population similar to that of expected Quebec pregnant women in 2015.
The 2015-2016 fiscal year budget impact was estimated from the Quebec healthcare system and calculated as the difference in the overall costs between the two alternatives.
The baseline cost for NIPT was pegged at $795 (Canadian dollars).
Compared to the existing screening program, Contingent NIPT would be implemented at an overall neutral cost, with a modest annual savings of 1.6% or $80,432.
The scenario accounted for a first screening step (SIPS) uptake of 50% and a NIPT uptake of 90%.
However, the proposed model considers only prenatal screening for singleton pregnancies, as recommended in Quebec, and pregnant women who decline prenatal screening follow the natural course of pregnancy. In addition, all pregnant women with a failure NIPT test outcome are retested.
“Our results provide an additional argument in favor of introducing NIPT as a contingent test in national Down syndrome screening programs,” wrote the authors.
Besides the affordability of Contingent NIPT, the screening program can be easily integrated into clinical practice as an add-on to the current Quebec practice, for better selecting pregnant women who should undergo invasive testing.
One limitation of the study, however, is that assumptions were made about the uptake rate of NIPT because the technology has yet to be incorporated into universal screening programs.
A second limitation is that the one-time costs of investment and the implementation of NIPT were excluded. Only direct costs related to the screening and diagnosis, as well as their short-time consequences, were included, based on the duration time of pregnancy. Hence, the total costs of the Contingent NIPT option might be higher than the cost of the current practice option during the first years of implementation.
But this extra cost might be offset by a decrease in cytologist services, according to the authors, because prenatal cytogenetics will continue to fall with the reduction in invasive procedures.
“Further research is needed to confirm if our results can be reproduced in other healthcare jurisdictions,” wrote the authors. However, some of our sensitivity analyses provide estimates of how NIPT could impact other jurisdictions since pregnancy trajectories are similar.”
Nshimyumukiza L, Beaumont JA, Rousseau F, Reinharz D. Introducing cell-free DNA noninvasive testing in a Down syndrome public health screening program: a budget impact analysis. Cost Eff Resour Alloc. 2020 Nov 4;18(1):49. doi:10.1186/s12962-020-00245-5