BACKGROUND
Maternal biologic factors can affect the fetal fraction in cell-free DNA-based prenatal
screening assays, thereby limiting the effectiveness. Higher rates of indeterminate
results because of a low fetal fraction have been described in cases of maternal autoimmune
disease in pregnancy. Existing studies are confounded by the concomitant maternal
use of anticoagulants, which may independently influence the test characteristics.
OBJECTIVE
This study aimed to evaluate the differences in fetal fraction, indeterminate results,
and total cell-free DNA concentration among women with an autoimmune disease in comparison
with controls, using our in-house developed, noninvasive prenatal screening platform
in the absence of maternal anticoagulation use.
STUDY DESIGN
This was a retrospective, single institution cohort study of a previously validated,
cell-free DNA-based, noninvasive prenatal screening assay using a low-pass whole-genome
sequencing platform between 2017 and 2019. A diagnosis of an autoimmune disease included
systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, inflammatory
bowel disease, and others. Immunomodulator therapies included biologics, corticosteroids,
hydroxychloroquine, azathioprine, and intravenous immunoglobulin. Women who were using
anticoagulants were excluded. We evaluated the association between autoimmune disease
and fetal cell-free DNA fraction, indeterminate results, and total cell-free DNA concentration
using univariate and multivariate analyses, stratified according to immunomodulator
therapy and adjusted for body mass index, fetal sex, and gestational age at sample
collection.
RESULTS
A total of 1445 patients met inclusion criteria. Of those, 43 women had a confirmed
autoimmune disease, with 25 of those not on immunomodulator therapy and 18 on immunomodulator
therapy. The mean fetal fraction for women with an autoimmune disease was significantly
lower than for controls (9.7% vs 11.9%; P=.004). The rate of indeterminate results was significantly higher among women with
an autoimmune disease than among controls (16.3% vs 3.5%; P<.001). The total cell-free DNA concentration was not statistically different between
the groups (94.8 pg/µL for women with an autoimmune disease vs 83.9 pg/µL for controls;
P=.06). In a logistic regression, women with an autoimmune disease had significantly
higher odds of receiving an indeterminate result than controls, (adjusted odds ratio,
5.3; 95% confidence interval, 2.0–14.2). Linear regression analysis showed a significant
negative association between having an autoimmune disease and the fetal cell-free
DNA fraction (aβ, −2.1; 95% confidence interval, −3.4 to −0.6).
When stratifying by treatment status, the mean fetal fraction was 9.8%, 9.6%, and
11.9% for women with an autoimmune disease not on immunomodulator therapy, women with
an autoimmune disease on immunomodulator therapy, and the controls, respectively (P=.02). The rate of indeterminate results increased in a stepwise fashion from 3.5%
to 11.1% to 20.0% for controls, women with an autoimmune disease on immunomodulator
therapy, and women with an autoimmune disease not on immunomodulator therapy, respectively
(P<.001).
Logistic regression analysis demonstrated higher odds of an indeterminate result for
women with an autoimmune disease not on immunomodulator therapy than for controls,
(adjusted odds ratio, 7.3; 95% confidence interval, 2.3–22.5). There was a negative
association between women with an autoimmune disease not on immunomodulator therapy
and the fetal fraction when compared with controls (aβ, −2.2; 95% confidence interval,
−4.2 to −0.3).
CONCLUSION
Women with an autoimmune disease have lower fetal cell-free DNA fractions and higher
rates of indeterminate results than women without an autoimmune disease. There was
no difference in total cell-free DNA concentration. Treatment of maternal autoimmune
diseases with immunomodulator therapy may decrease the indeterminate result rate.
Key words
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References
- Cell-free plasma DNA as a predictor of outcome in severe sepsis and septic shock.Clin Chem. 2008; 54: 1000-1007
- Plasma DNA, prediction and post-traumatic complications.Clin Chim Acta. 2001; 313: 81-85
- Prognostic use of circulating plasma nucleic acid concentrations in patients with acute stroke.Clin Chem. 2003; 49: 562-569
- Donor-specific cell-free DNA as a biomarker in solid organ transplantation. A systematic review.Transplantation. 2019; 103: 273-283
- Plasma DNA tissue mapping by genome-wide methylation sequencing for noninvasive prenatal, cancer, and transplantation assessments.Proc Natl Acad Sci U S A. 2015; 112: E5503-E5512
- Cell-free DNA as a biomarker in autoimmune rheumatic diseases.Front Immunol. 2019; 10: 502
- [Nuclear acids in human blood plasma].C R Seances Soc Biol Fil. 1948; 142: 241-243
- The diverse origins of circulating cell-free DNA in the human body: a critical re-evaluation of the literature.Biol Rev Camb Philos Soc. 2018; 93: 1649-1683
- Noninvasive prenatal testing and incidental detection of occult maternal malignancies.JAMA. 2015; 314: 162-169
- Quantitative analysis of fetal DNA in maternal plasma and serum: implications for noninvasive prenatal diagnosis.Am J Hum Genet. 1998; 62: 768-775
- The impact of maternal plasma DNA fetal fraction on next generation sequencing tests for common fetal aneuploidies.Prenat Diagn. 2013; 33: 667-674
- Fetal fraction in maternal plasma cell-free DNA at 11-13 weeks’ gestation: relation to maternal and fetal characteristics.Ultrasound Obstet Gynecol. 2013; 41: 26-32
- The implications of non-invasive prenatal testing failures: a review of an under-discussed phenomenon.Prenat Diagn. 2016; 36: 391-396
- Cell-free DNA analysis for noninvasive examination of trisomy.N Engl J Med. 2015; 372: 1589-1597
- Analysis of cell-free DNA in maternal blood in screening for aneuploidies: updated meta-analysis.Ultrasound Obstet Gynecol. 2017; 50: 302-314
- The influence of low molecular weight heparin medication on plasma DNA in pregnant women.Prenat Diagn. 2015; 35: 1155-1157
- The association between anticoagulation therapy, maternal characteristics, and a failed cfDNA test due to a low fetal fraction.Prenat Diagn. 2017; 37: 1125-1129
- Screening for trisomies by cell-free DNA testing of maternal blood: consequences of a failed result.Ultrasound Obstet Gynecol. 2016; 47: 698-704
- Prenatal cell-free DNA screening test failures: a systematic review of failure rates, risks of Down syndrome, and impact of repeat testing.Genet Med. 2018; 20: 1312-1323
- Autoimmune disorders but not heparin are associated with cell-free fetal DNA test failure.J Transl Med. 2018; 16: 335
- Repeated failed non-invasive prenatal testing in a woman with immune thrombocytopenia and antiphospholipid syndrome: lessons learnt.BMJ Case Rep. 2016; 2016bcr2016216593
- Repeated failed non-invasive prenatal testing owing to low cell-free fetal DNA fraction and increased variance in a woman with severe autoimmune disease.Ultrasound Obstet Gynecol. 2014; 44: 242-243
- Nonreportable rates and cell-free DNA profiles in noninvasive prenatal testing among women with heparin treatment.Prenat Diagn. 2020; 40: 838-845
- The REDCap consortium: building an international community of software platform partners.J Biomed Inform. 2019; 95103208
- Research Electronic Data Capture (REDCap)–a metadata-driven methodology and workflow process for providing translational research informatics support.J Biomed Inform. 2009; 42: 377-381
- Size-based molecular diagnostics using plasma DNA for noninvasive prenatal testing.Proc Natl Acad Sci U S A. 2014; 111: 8583-8588
- Effects of medication intake in early pregnancy on the fetal fraction of cell-free DNA testing.Prenat Diagn. 2019; 39: 361-368
- Circulating cell free DNA testing: are some test failures informative?.Prenat Diagn. 2015; 35: 289-293
- Increased levels of circulating DNA in patients with systemic autoimmune diseases: a possible marker of disease activity in Sjögren's syndrome.Lupus. 2011; 20: 928-935
- Circulating DNA in rheumatoid arthritis: pathological changes and association with clinically used serological markers.Arthritis Res Ther. 2017; 19: 85
- Correlation between cell free DNA levels and medical evaluation of disease progression in systemic lupus erythematosus patients.Cell Immunol. 2014; 292: 32-39
- High levels of circulating cell-free DNA are a biomarker of active SLE.Eur J Clin Invest. 2018; 48: e13015
- Release of neutrophil extracellular traps by neutrophils stimulated with antiphospholipid antibodies: a newly identified mechanism of thrombosis in the antiphospholipid syndrome.Arthritis Rheumatol. 2015; 67: 2990-3003
- Antiphospholipid antibody-activated NETs exacerbate trophoblast and endothelial cell injury in obstetric antiphospholipid syndrome.J Cell Mol Med. 2020; 24: 6690-6703
- Nuclear and mitochondrial circulating cell-free DNA is increased in patients with inflammatory bowel disease in clinical remission.Front Med (Lausanne). 2020; 7593316
- Considering sex as a biological variable in preclinical research.FASEB J. 2017; 31: 29-34
- Sex as a biological variable: a 5-year progress report and call to action.J Womens Health (Larchmt). 2020; 29: 858-864
Article info
Publication history
Published online: August 17, 2021
Accepted:
August 11,
2021
Received:
July 28,
2021
Footnotes
R.S. and S.D. are combined last senior authors.
The authors report no conflict of interest.
This study was funded by the National Institutes of Health (grant number K08HD067221). The funders had no role in the study design, collection, analysis, or interpretation of data, or in the writing of the report or decision to submit the article for publication. Additional funding for this study was received from the National Center for Advancing Translational Sciences (grant numbers UL1TR002319, KL2TR002317, and TL1TR002318).
Preliminary findings of this study were presented as a poster at the 41st annual meeting of the Society for Maternal-Fetal Medicine, held virtually, January 25–30, 2021.
Cite this article as: MacKinnon HJ, Kolarova TR, Katz R, et al. The impact of maternal autoimmune disease on cell-free DNA test characteristics. Am J Obstet Gynecol MFM 2021;XX:x.ex–x.ex.
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Published by Elsevier Inc.
