Screening for pre-eclampsia by maternal serum glycosylated fibronectin and angiogenic markers at 36 weeks' gestation

OBJECTIVES

First, to examine the predictive performance of maternal serum glycosylated fibronectin (GlyFn) at 35 + 0 to 36 + 6 weeks' gestation in screening for delivery with pre-eclampsia (PE) and delivery with gestational hypertension (GH) at ≥ 37 weeks' gestation, both within 3 weeks and at any time after the examination. Second, to compare the predictive performance for delivery with PE and delivery with GH of various combinations of biomarkers, including GlyFn, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), serum placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1). Third, to compare the predictive performance for delivery with PE and delivery with GH by serum PlGF concentration, sFlt-1/PlGF concentration ratio and the competing-risks model with different combinations of biomarkers as above. Fourth, to compare the predictive performance of screening at 11 + 0 to 13 + 6 weeks vs 35 + 0 to 36 + 6 weeks for delivery with PE and delivery with GH at ≥ 37 weeks' gestation.

METHODS

This was a case-control study in which maternal serum GlyFn was measured in stored samples from a non-intervention screening study in singleton pregnancies at 35 + 0 to 36 + 6 weeks' gestation using a point-of-care device. We used samples from women who delivered at ≥ 37 weeks' gestation, including 100 who developed PE, 100 who developed GH and 600 controls who did not develop PE or GH. In all cases, MAP, UtA-PI, PlGF and sFlt-1 were measured during the routine visit at 35 + 0 to 36 + 6 weeks. We used samples from patients that had been examined previously at 11 + 0 to 13 + 6 weeks' gestation. Levels of GlyFn were transformed to multiples of the expected median (MoM) values after adjusting for maternal demographic characteristics and elements from the medical history. Similarly, the measured values of MAP, UtA-PI, PlGF and sFlt-1 were converted to MoM. The competing-risks model was used to combine the prior distribution of the gestational age at delivery with PE, obtained from maternal risk factors, with various combinations of biomarker MoM values to derive the patient-specific risks of delivery with PE. The performance of screening of different strategies was estimated by examining the detection rate (DR) at a 10% fixed false-positive rate (FPR) and McNemar's test was used to compare the DRs between the different methods of screening.

RESULTS

The DR, at 10% FPR, of screening by the triple test (maternal risk factors plus MAP, PlGF and sFlt-1) was 83.7% (95% CI, 70.3-92.7%) for delivery with PE within 3 weeks of screening and 80.0% (95% CI, 70.8-87.3%) for delivery with PE at any time after screening, and this performance was not improved by the addition of GlyFn. The performance of screening by a combination of maternal risk factors, MAP, PlGF and GlyFn was similar to that of the triple test, both for delivery with PE within 3 weeks and at any time after screening. The performance of screening by a combination of maternal risk factors, MAP, UtA-PI and GlyFn was similar to that of the triple test, and they were both superior to screening by low PlGF concentration (PE within 3 weeks: DR, 65.3% (95% CI, 50.4-78.3%); PE at any time: DR, 56.0% (95% CI, 45.7-65.9%)) or high sFlt-1/PlGF concentration ratio (PE within 3 weeks: DR, 73.5% (95% CI, 58.9-85.1%); PE at any time: DR, 63.0% (95% CI, 52.8-72.4%)). The predictive performance of screening at 35 + 0 to 36 + 6 weeks' gestation for delivery with PE and delivery with GH at ≥ 37 weeks' gestation was by far superior to screening at 11 + 0 to 13 + 6 weeks.

CONCLUSION

GlyFn is a potentially useful biomarker in third-trimester screening for term PE and term GH, but the findings of this case-control study need to be validated by prospective screening studies. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Prediction using serum glycosylated fibronectin and angiogenic factors of superimposed pre-eclampsia in women with chronic hypertension

OBJECTIVE

To compare the predictive performance for delivery with pre-eclampsia (PE) within 2 weeks of assessment in women with chronic hypertension at 24-41 weeks' gestation between serum glycosylated fibronectin (GlyFn) concentration, serum placental growth factor (PlGF) concentration and soluble fms-like tyrosine kinase-1 (sFlt-1) to PlGF concentration ratio.

METHODS

This was a prospective study of 104 women with a singleton pregnancy and chronic hypertension presenting at 24-41 weeks' gestation. Twenty-six (25.0%) cases developed superimposed PE within 2 weeks of sampling. We compared the predictive performance for superimposed PE between GlyFn, PlGF and the sFlt-1/PlGF ratio at a fixed screen-positive rate of approximately 10%.

RESULTS

The median gestational age at sampling was 34.1 (interquartile range, 31.5-35.6) weeks and 84.6% (88/104) of cases were sampled at < 36 weeks. The predictive performance for superimposed PE of the three methods of screening was similar, with detection rates of about 23-27%, at a screen-positive rate of 11% and a false-positive rate of about 5%.

CONCLUSIONS

Measurement of GlyFn is a simple point-of-care test that can be carried out without need for a laboratory and provide results within 10 min of testing. In this respect, it could potentially replace the angiogenic markers that are used currently in the prediction of imminent PE in high-risk women. However, neither GlyFn nor angiogenic factors are likely to improve the management of women with chronic hypertension because their predictive performance for superimposed PE is poor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Prediction using serum glycosylated fibronectin of imminent pre-eclampsia in women with new-onset hypertension

OBJECTIVE

To compare the predictive performance for delivery with pre-eclampsia (PE) within 2 weeks after assessment in women with new-onset hypertension at 24-41 weeks' gestation between serum glycosylated fibronectin (GlyFn) concentration, serum placental growth factor (PlGF) concentration and soluble fms-like tyrosine kinase-1 (sFlt-1) to PlGF concentration ratio.

METHODS

This was a prospective observational study of 409 women with a singleton pregnancy presenting at 24-41 weeks' gestation with new-onset hypertension. The recommended cut-off for sFlt-1/PlGF ratio for the prediction of PE in the platform used in this study is 85; the appropriate cut-offs for GlyFn and PlGF were determined to achieve the same screen-positive rate as that of sFlt-1/PlGF ratio > 85. We then compared the predictive performance for delivery with PE within 2 weeks after presentation between GlyFn, PlGF and sFlt-1/PlGF, both overall and in subgroups according to gestational age at presentation.

RESULTS

Delivery with PE within 2 weeks occurred in 93 (22.7%) cases. The screen-positive rate for sFlt-1/PlGF ratio > 85 was 46.2%. The cut-off corresponding to a screen-positive rate of 46.2% was 75 pg/mL for PlGF and 510 µg/mL for GlyFn. The overall detection rate for delivery with PE within 2 weeks after presentation was 62.4% (95% CI, 51.7-72.2%) for GlyFn and sFlt-1/PlGF and 60.2% (95% CI, 49.5-70.2%) for PlGF. In all women who delivered with PE within 2 weeks after presentation at < 34 weeks' gestation and in about 60-70% of those presenting at < 38 weeks, GlyFn and sFlt-1/PlGF were increased and PlGF was reduced. However, the screen-positive rate for these tests was very high at about 45%. The predictive performance for delivery with PE within 2 weeks after presentation at ≥ 38 weeks' gestation was poorer for all three methods of screening, with detection rates of 47-63% at screen-positive rates of 40-50%.

CONCLUSIONS

In women with new-onset hypertension, the predictive performance for delivery with PE within 2 weeks after presentation for serum GlyFn is similar to that of PlGF and the sFlt-1/PlGF ratio, but GlyFn may be the preferred option because it is a rapid point-of-care test. However, the predictive performance for all tests is relatively poor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Glycosylated fibronectin improves first-trimester prediction of pre-eclampsia

OBJECTIVE

To determine whether maternal serum glycosylated fibronectin (GlyFn) level in the first trimester increases the sensitivity of the Fetal Medicine Foundation (FMF) triple test, which incorporates mean arterial pressure, uterine artery pulsatility index and placental growth factor, when screening for pre-eclampsia (PE) in an Asian population.

METHODS

This was a nested case-control study of Chinese women with a singleton pregnancy who were screened for PE at 11-13 weeks' gestation as part of a non-intervention study between December 2016 and June 2018. GlyFn levels were measured retrospectively in archived serum from 1685 pregnancies, including 101 with PE, using an enzyme-linked immunosorbent assay (ELISA), and from 448 pregnancies, including 101 with PE, using a point-of-care (POC) device. Concordance between ELISA and POC tests was assessed using Lin's correlation coefficient and Passing-Bablok and Bland-Altman analyses. GlyFn was transformed into multiples of the median (MoM) to adjust for maternal and pregnancy characteristics. GlyFn MoM was compared between PE and non-PE pregnancies, and the association between GlyFn MoM and gestational age at delivery with PE was assessed. Risk for developing PE was estimated using the FMF competing-risks model. Screening performance for preterm and any-onset PE using different biomarker combinations was quantified by area under the receiver-operating-characteristics curve (AUC) and detection rate (DR) at a 10% fixed false-positive rate (FPR). Differences in AUC between biomarker combinations were compared using the DeLong test.

RESULTS

The concordance correlation coefficient between ELISA and POC measurements was 0.86 (95% CI, 0.83-0.88). Passing-Bablok analysis indicated proportional bias (slope, 1.08 (95% CI, 1.04-1.14)), with POC GlyFn being significantly higher compared with ELISA GlyFn. ELISA GlyFn in non-PE pregnancies was independent of gestational age at screening (P = 0.11), but significantly dependent on maternal age (P < 0.003), weight (P < 0.0002), height (P = 0.001), parity (P < 0.02) and smoking status (P = 0.002). Compared with non-PE pregnancies, median GlyFn MoM using ELISA and POC testing was elevated significantly in those with preterm PE (1.23 vs 1.00; P < 0.0001 and 1.18 vs 1.00; P < 0.0001, respectively) and those with term PE (1.26 vs 1.00; P < 0.0001 and 1.22 vs 1.00; P < 0.0001, respectively). GlyFn MoM was not correlated with gestational age at delivery with PE (P = 0.989). Adding GlyFn to the FMF triple test for preterm PE increased significantly the AUC from 0.859 to 0.896 (P = 0.012) and increased the DR at 10% FPR from 64.9% (95% CI, 48.7-81.1%) to 82.9% (95% CI, 66.4-93.4%). The corresponding DRs at 10% FPR for any-onset PE were 52.5% (95% CI, 42.3-62.5%) and 65.4% (95% CI, 55.2-74.5%), respectively.

CONCLUSIONS

Adding GlyFn to the FMF triple test increased the screening sensitivity for both preterm and any-onset PE in an Asian population. Prospective non-intervention studies are needed to confirm these initial findings. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Glycosylated fibronectin point-of-care test for diagnosis of pre-eclampsia in a low-resource setting: a prospective Southeast Asian population study

OBJECTIVE

To determine the performance of a glycosylated fibronectin (GlyFn) point-of-care (POC) test for pre-eclampsia (PE) in a large Southeast Asian cohort (India) in comparison to previously described biomarkers.

DESIGN

A total of 798 pregnant women at ≥20 weeks of gestation were enrolled in a prospective case-control study. Study participants included 469 normotensive women with urinary mg protein/mmol creatinine ratio <0.3, 135 with PE (hypertension with urinary mg protein/mmol creatinine ratio ≥0.3) and 194 with gestational hypertension (hypertension with urinary mg protein/mmol creatinine ratio <0.3).

METHODS

GlyFn levels were determined using a POC device and PIGF, sFlt-1 and PAPPA2 levels were determined by immunoassay. Performance was assessed using logistic regression modelling and receiver-operating characteristic (ROC) curves. Classification performance and positive and negative predictive values are reported at specific thresholds.

RESULTS

Increased levels of GlyFn, soluble fms-like tyrosine kinase-1 (sFlt-1) and pregnancy-associated placental protein A2 (PAPPA2), and decreased levels of placental growth factor (PlGF) were significantly associated (P < 0.01) with clinically defined PE. Area under the ROC (AUROC) values with 95% confidence intervals were: GlyFn, 0.99 (0.98-0.99); PlGF, 0.96 (0.94-0.98); sFlt-1, 0.86 (0.83-0.89); and PAPPA2, 0.96 (0.94-0.97). Of subjects with GH, 48% were positive for more than two PE biomarkers, and 70% of these delivered preterm.

CONCLUSIONS

The Lumella™ GlyFn POC test has been validated in a low/middle-income country setting for PE diagnosis and may be a useful adjunctive tool for early identification, appropriate triage, and improved outcomes.

TWEETABLE ABSTRACT

The Lumella™ point-of-care test had excellent performance in diagnosing PE in a large Southeast Asian cohort.

Screening of gestational diabetes mellitus in early pregnancy by oral glucose tolerance test and glycosylated fibronectin: study protocol for an international, prospective, multicentre cohort trial

INTRODUCTION

As the accurate diagnosis and treatment of gestational diabetes mellitus (GDM) is of increasing importance; new diagnostic approaches for the assessment of GDM in early pregnancy were recently suggested. We evaluate the diagnostic power of an 'early' oral glucose tolerance test (OGTT) 75 g and glycosylated fibronectin (glyFn) for GDM screening in a normal cohort.

METHODS AND ANALYSIS

In a prospective cohort study, 748 singleton pregnancies are recruited in 6 centres in Switzerland, Austria and Germany. Women are screened for pre-existing diabetes mellitus and GDM by an 'early' OGTT 75 g and/or the new biomarker, glyFn, at 12-15 weeks of gestation. Different screening strategies are compared to evaluate the impact on detection of GDM by an OGTT 75 g at 24-28 weeks of gestation as recommended by the International Association of Diabetes and Pregnancy Study Groups (IADPSG). A new screening algorithm is created by using multivariable risk estimation based on 'early' OGTT 75 g and/or glyFn results, incorporating maternal risk factors. Recruitment began in May 2014.

ETHICS AND DISSEMINATION

This study received ethical approval from the ethics committees in Basel, Zurich, Vienna, Salzburg and Freiburg. It was registered under http://www.ClinicalTrials.gov (NCT02035059) on 12 January 2014. Data will be presented at international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02035059.

Maternal serum glycosylated fibronectin as a point-of-care biomarker for assessment of preeclampsia

OBJECTIVE

We assessed the association of glycosylated fibronectin (GlyFn) with preeclampsia and its performance in a point-of-care (POC) test.

STUDY DESIGN

GlyFn, placental growth factor (PlGF), and soluble vascular endothelial growth factor receptor 1 (sFlt1) levels were determined in serum samples from 107 pregnant women. In all, 45 were normotensive and 62 were diagnosed with preeclampsia. The ability of GlyFn to assess preeclampsia status and relationships between GlyFn and maternal characteristics and pregnancy outcomes were analyzed.

RESULTS

GlyFn serum levels in the first trimester were significantly higher in women with preeclampsia (P < .01) and remained higher throughout pregnancy (P < .01). GlyFn, sFlt1, PlGF, and the sFlt1/PlGF ratio were significantly associated (P < .01) with preeclampsia status, and the classification performance of these analytes represented by area under the receiver operating characteristic curve was 0.99, 0.96, 0.94, and 0.98, respectively, with 95% confidence intervals of 0.98-1.00, 0.89-1.00, 0.86-1.00, and 0.94-1.00, respectively. Increased GlyFn levels were significantly associated with gestational age at delivery (P < .01), blood pressure (P = .04), and small-for-gestational-age neonates. Repeated-measures analysis of the difference in weekly GlyFn change in the third trimester demonstrated that mild preeclampsia was associated with a weekly change of 81.7 μg/mL (SE 94.1) vs 195.2 μg/mL (SE 88.2) for severe preeclampsia. The GlyFn POC demonstrated similar performance to a plate assay with an area under the receiver operating characteristic curve of 0.93 and 95% confidence interval of 0.85-1.00.

CONCLUSION

GlyFn is a robust biomarker for monitoring of preeclampsia in both a standard and POC format, which supports its utility in diverse settings.

Maternal serum biomarkers for risk assessment in gestational diabetes. A potential universal screening test to predict GDM status

The prevalence of gestational diabetes mellitus (GDM) is increasing because of the worldwide obesity/diabetes epidemic. The complications of untreated GDM affect both the mother and baby and include complications during pregnancy as well as increased risk of subsequent type-2 diabetes in mothers and offspring. Standard tests for hyperglycemia in diabetes, such as fasting glucose and hemoglobin (HbA1c), are currently not recommended for GDM screening. Instead, an oral glucose tolerance test is specified, which is invasive, time-consuming, and not easily accessible to many at-risk populations. In this study, we describe a multi-analyte maternal serum profile test that incorporates novel glycoprotein biomarkers and previously described GDM-associated markers. In screening for GDM by multi-analyte panel, the detection rate was 87% at a false-positive rate of 1%.