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The European Journal of Health... Sep 2018The aim of this paper was to conduct a systematic review of the cost-effectiveness of the analysis of cell-free DNA in maternal blood, often called the non-invasive... (Review)
Review
The aim of this paper was to conduct a systematic review of the cost-effectiveness of the analysis of cell-free DNA in maternal blood, often called the non-invasive prenatal test (NIPT), in the prenatal screening of trisomy in chromosomes 21, 18 and 13. MEDLINE, MEDLINE in process, EMBASE, and Cochrane Library were searched in April 2017. We selected: (1) economic evaluations that estimated the costs and detected cases of trisomy 21, 18 or 13; (2) comparisons of prenatal screening with NIPT (universal or contingent strategies) and the usual screening without NIPT, (3) in pregnant women with any risk of foetal anomalies. Studies were reviewed by two researchers. Data were extracted, the methodological quality was assessed and a narrative synthesis was prepared. In total, 12 studies were included, four of them performed in Europe. Three studies evaluated NIPT as a contingent test, three studies evaluated a universal NIPT, and six studies evaluated both. The results are heterogeneous, especially for the contingent NIPT where the results range from NIPT being dominant to a dominated strategy. Universal NIPT was found to be more effective but also costlier than the usual screening, with very high incremental cost-effectiveness ratios. One advantage of screening with NIPT is lower invasive procedure-related foetal losses than with usual screening. In conclusion, the cost-effectiveness of contingent NIPT is uncertain according to several studies, while the universal NIPT is not cost-effective currently.
Topics: Cell-Free Nucleic Acids; Cost-Benefit Analysis; Down Syndrome; Europe; Female; Humans; Pregnancy; Trisomy; Trisomy 13 Syndrome; Trisomy 18 Syndrome
PubMed: 29249015
DOI: 10.1007/s10198-017-0946-y -
The Cochrane Database of Systematic... Nov 2017Common fetal aneuploidies include Down syndrome (trisomy 21 or T21), Edward syndrome (trisomy 18 or T18), Patau syndrome (trisomy 13 or T13), Turner syndrome (45,X),... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Common fetal aneuploidies include Down syndrome (trisomy 21 or T21), Edward syndrome (trisomy 18 or T18), Patau syndrome (trisomy 13 or T13), Turner syndrome (45,X), Klinefelter syndrome (47,XXY), Triple X syndrome (47,XXX) and 47,XYY syndrome (47,XYY). Prenatal screening for fetal aneuploidies is standard care in many countries, but current biochemical and ultrasound tests have high false negative and false positive rates. The discovery of fetal circulating cell-free DNA (ccfDNA) in maternal blood offers the potential for genomics-based non-invasive prenatal testing (gNIPT) as a more accurate screening method. Two approaches used for gNIPT are massively parallel shotgun sequencing (MPSS) and targeted massively parallel sequencing (TMPS).
OBJECTIVES
To evaluate and compare the diagnostic accuracy of MPSS and TMPS for gNIPT as a first-tier test in unselected populations of pregnant women undergoing aneuploidy screening or as a second-tier test in pregnant women considered to be high risk after first-tier screening for common fetal aneuploidies. The gNIPT results were confirmed by a reference standard such as fetal karyotype or neonatal clinical examination.
SEARCH METHODS
We searched 13 databases (including MEDLINE, Embase and Web of Science) from 1 January 2007 to 12 July 2016 without any language, search filter or publication type restrictions. We also screened reference lists of relevant full-text articles, websites of private prenatal diagnosis companies and conference abstracts.
SELECTION CRITERIA
Studies could include pregnant women of any age, ethnicity and gestational age with singleton or multifetal pregnancy. The women must have had a screening test for fetal aneuploidy by MPSS or TMPS and a reference standard such as fetal karyotype or medical records from birth.
DATA COLLECTION AND ANALYSIS
Two review authors independently carried out study selection, data extraction and quality assessment (using the QUADAS-2 tool). Where possible, hierarchical models or simpler alternatives were used for meta-analysis.
MAIN RESULTS
Sixty-five studies of 86,139 pregnant women (3141 aneuploids and 82,998 euploids) were included. No study was judged to be at low risk of bias across the four domains of the QUADAS-2 tool but applicability concerns were generally low. Of the 65 studies, 42 enrolled pregnant women at high risk, five recruited an unselected population and 18 recruited cohorts with a mix of prior risk of fetal aneuploidy. Among the 65 studies, 44 evaluated MPSS and 21 evaluated TMPS; of these, five studies also compared gNIPT with a traditional screening test (biochemical, ultrasound or both). Forty-six out of 65 studies (71%) reported gNIPT assay failure rate, which ranged between 0% and 25% for MPSS, and between 0.8% and 7.5% for TMPS.In the population of unselected pregnant women, MPSS was evaluated by only one study; the study assessed T21, T18 and T13. TMPS was assessed for T21 in four studies involving unselected cohorts; three of the studies also assessed T18 and 13. In pooled analyses (88 T21 cases, 22 T18 cases, eight T13 cases and 20,649 unaffected pregnancies (non T21, T18 and T13)), the clinical sensitivity (95% confidence interval (CI)) of TMPS was 99.2% (78.2% to 100%), 90.9% (70.0% to 97.7%) and 65.1% (9.16% to 97.2%) for T21, T18 and T13, respectively. The corresponding clinical specificity was above 99.9% for T21, T18 and T13.In high-risk populations, MPSS was assessed for T21, T18, T13 and 45,X in 30, 28, 20 and 12 studies, respectively. In pooled analyses (1048 T21 cases, 332 T18 cases, 128 T13 cases and 15,797 unaffected pregnancies), the clinical sensitivity (95% confidence interval (CI)) of MPSS was 99.7% (98.0% to 100%), 97.8% (92.5% to 99.4%), 95.8% (86.1% to 98.9%) and 91.7% (78.3% to 97.1%) for T21, T18, T13 and 45,X, respectively. The corresponding clinical specificities (95% CI) were 99.9% (99.8% to 100%), 99.9% (99.8% to 100%), 99.8% (99.8% to 99.9%) and 99.6% (98.9% to 99.8%). In this risk group, TMPS was assessed for T21, T18, T13 and 45,X in six, five, two and four studies. In pooled analyses (246 T21 cases, 112 T18 cases, 20 T13 cases and 4282 unaffected pregnancies), the clinical sensitivity (95% CI) of TMPS was 99.2% (96.8% to 99.8%), 98.2% (93.1% to 99.6%), 100% (83.9% to 100%) and 92.4% (84.1% to 96.5%) for T21, T18, T13 and 45,X respectively. The clinical specificities were above 100% for T21, T18 and T13 and 99.8% (98.3% to 100%) for 45,X. Indirect comparisons of MPSS and TMPS for T21, T18 and 45,X showed no statistical difference in clinical sensitivity, clinical specificity or both. Due to limited data, comparative meta-analysis of MPSS and TMPS was not possible for T13.We were unable to perform meta-analyses of gNIPT for 47,XXX, 47,XXY and 47,XYY because there were very few or no studies in one or more risk groups.
AUTHORS' CONCLUSIONS
These results show that MPSS and TMPS perform similarly in terms of clinical sensitivity and specificity for the detection of fetal T31, T18, T13 and sex chromosome aneuploidy (SCA). However, no study compared the two approaches head-to-head in the same cohort of patients. The accuracy of gNIPT as a prenatal screening test has been mainly evaluated as a second-tier screening test to identify pregnancies at very low risk of fetal aneuploidies (T21, T18 and T13), thus avoiding invasive procedures. Genomics-based non-invasive prenatal testing methods appear to be sensitive and highly specific for detection of fetal trisomies 21, 18 and 13 in high-risk populations. There is paucity of data on the accuracy of gNIPT as a first-tier aneuploidy screening test in a population of unselected pregnant women. With respect to the replacement of invasive tests, the performance of gNIPT observed in this review is not sufficient to replace current invasive diagnostic tests.We conclude that given the current data on the performance of gNIPT, invasive fetal karyotyping is still the required diagnostic approach to confirm the presence of a chromosomal abnormality prior to making irreversible decisions relative to the pregnancy outcome. However, most of the gNIPT studies were prone to bias, especially in terms of the selection of participants.
Topics: Aneuploidy; Cell-Free Nucleic Acids; Chromosome Disorders; Disorders of Sex Development; Female; Fetal Diseases; High-Throughput Nucleotide Sequencing; Humans; Pregnancy; Pregnancy, High-Risk; Prenatal Diagnosis
PubMed: 29125628
DOI: 10.1002/14651858.CD011767.pub2 -
Prenatal Diagnosis Mar 2020To evaluate the test accuracy of non-invasive prenatal testing (NIPT) for fetal trisomy 21, 18, and 13 using cell-free (cf) DNA analysis in maternal plasma with... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To evaluate the test accuracy of non-invasive prenatal testing (NIPT) for fetal trisomy 21, 18, and 13 using cell-free (cf) DNA analysis in maternal plasma with microarray quantitation.
METHOD
Systematic review and meta-analysis. Searches in MEDLINE, Pre-MEDLINE, EMBASE, Web of Science, and the Cochrane Library to 09.07.2018.
RESULTS
Five studies analyzing 3074 samples, including 187 trisomy 21, 43 trisomy 18, and 19 trisomy 13 cases, were identified. Risk of bias was high in all studies, introduced particularly by exclusions from analysis and by the role of the sponsor. Sensitivity of microarray-based cfDNA testing was 99.5% (95%CI 96.3%-99.9%) for trisomy 21, 97.7% (95%CI 87.9%-99.6%) for trisomy 18, and 100% (95%CI 83.2%-100%) for trisomy 13. Specificity was 100% (95% CI 99.87%-100%) for trisomy 21, 99.97% (95%CI 99.81%-99.99%) for trisomy 18, and 99.97% (95%CI 99.81%-99.99%) for trisomy 13. Pooled test failure rate was 1.1%. A direct comparison of microarray- and sequencing-based cfDNA found equivalent test accuracy.
CONCLUSION
Included studies suggest that NIPT using microarray-based cfDNA testing has high sensitivity and specificity for detecting fetal trisomy 21, 18, and 13. However, the evidence base is small and at high risk of bias.
Topics: Cell-Free Nucleic Acids; Down Syndrome; Female; High-Throughput Nucleotide Sequencing; Humans; Microarray Analysis; Noninvasive Prenatal Testing; Pregnancy; Sensitivity and Specificity; Sequence Analysis, DNA; Trisomy 13 Syndrome; Trisomy 18 Syndrome
PubMed: 31834626
DOI: 10.1002/pd.5621 -
BMC Pregnancy and Childbirth Jan 2019Non-invasive prenatal testing (NIPT) can be used to accurately detect fetal chromosomal anomalies early in pregnancy by assessing cell-free fetal DNA present in maternal...
BACKGROUND
Non-invasive prenatal testing (NIPT) can be used to accurately detect fetal chromosomal anomalies early in pregnancy by assessing cell-free fetal DNA present in maternal blood. The rapid diffusion of NIPT, as well as the ease and simplicity of the test raises concerns around informed decision-making and the potential for routinization. Introducing NIPT in a way that facilitates informed and autonomous decisions is imperative to the ethical application of this technology. We approach this imperative by systematically reviewing and synthesizing primary qualitative research on women's experiences with and preferences for informed decision-making around NIPT.
METHODS
We searched multiple bibliographic databases including Ovid MEDLINE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and ISI Web of Science Social Sciences Citation Index (SSCI). Our review was guided by integrative qualitative meta-synthesis, and we used a staged coding process similar to that of grounded theory to conduct our analysis.
RESULTS
Thirty empirical primary qualitative research studies were eligible for inclusion. Women preferred to learn about NIPT from their clinicians, but they expressed dissatisfaction with the quality and quantity of information provided during counselling and often sought information from a variety of other sources. Women generally had a good understanding of test characteristics, and the factors of accuracy, physical risk, and test timing were the critical information elements that they used to make informed decisions around NIPT. Women often described NIPT as easy or just another blood test, highlighting threats to informed decision-making such as routinization or a pressure to test.
CONCLUSIONS
Women's unique circumstances modulate the information that they value and require most in the context of making an informed decision. Widened availability of trustworthy information about NIPT as well as careful attention to the facilitation of counselling may help facilitate informed decision-making.
TRIAL REGISTRATION
PROSPERO 2018 CRD42018086261 .
Topics: Cell-Free Nucleic Acids; Choice Behavior; Decision Making; Down Syndrome; Female; Humans; Informed Consent; Patient Preference; Pregnancy; Pregnant Women; Prenatal Diagnosis; Qualitative Research; Trisomy 13 Syndrome; Trisomy 18 Syndrome
PubMed: 30642270
DOI: 10.1186/s12884-018-2168-4