Introducing the non-invasive prenatal test for trisomy 21 in Belgium: a cost-consequences analysis

Abstract

Background: The first- and second-trimester screening for trisomy 21 (T21) are reimbursed for all pregnant women in Belgium. Using a cut-off risk of 1:300 for T21, about 5% of all pregnant women are referred for definitive prenatal diagnosis using an invasive test, at a sensitivity of (only) 72.5%. The sensitivity and specificity of the non-invasive prenatal test (NIPT) are over 99% but come at a cost of €460 (£373) per test. The objective is to estimate the consequences of introducing NIPT for the detection of T21.

Methods: A cost-consequences analysis was performed presenting the impact on benefits, harms and costs. Context-specific real-world information was available to set up a model reflecting the current screening situation in Belgium. This model was used to construct the second and first line NIPT screening scenarios applying information from the literature on NIPT's test accuracy.

Results: Introducing NIPT in the first or second line reduces harm by decreasing the number of procedure-related miscarriages after invasive testing. In contrast with NIPT in the second line, offering NIPT in the first line additionally will miss fewer cases of T21 due to less false-negative test results. The introduction of NIPT in the second line results in cost savings, which is not true for NIPT at the current price in the first line. If NIPT is offered to all pregnant women, the price should be lowered to about €150 to keep the screening cost per T21 diagnosis constant.

Conclusions: In Belgium, the introduction and reimbursement of NIPT as a second line triage test significantly reduces procedure-related miscarriages without increasing the short-term screening costs. Offering and reimbursing NIPT in the first line to all pregnant women is preferred in the long term, as it would, in addition, miss fewer cases of T21. However, taking into account the government's limited resources for universal reimbursement, the price of NIPT should first be lowered substantially before this can be realised.

Keywords: Cost-Benefit Analysis; Diagnostic Techniques, Obstetrical and Gynecological; Down Syndrome.

Figure 1

Screening strategy with NIPT as a triage test. NIPT, non-invasive prenatal test; T21, trisomy 21; NT, nuchal translucency; hosp.leak., hospitalisation for leakage; inv., invasive; pr.rel.misc., procedure-related miscarriage; rep., repeat; term.: termination.

Figure 2

Presentation of most relevant screening scenarios. See the discussion for further explanation on the interpretation of the line presenting the ‘average cost per T21 detected (current screening)’. Remark: this figure does not present other outcomes of importance, such as the number of procedure-related miscarriages (NIPT, non-invasive prenatal test; T21, trisomy 21).