Early onset preeclampsia is associated with an elevated mean platelet volume (MPV) and a greater rise in MPV from time of booking compared with pregnant controls: results of the CAPE study

First-Trimester Preeclampsia-Induced Disturbance in Maternal Blood Serum Proteome: A Pilot Study

Preeclampsia (PE) is a complex and multifaceted obstetric syndrome characterized by several distinct molecular subtypes. It complicates up to 5% of pregnancies and significantly contributes to maternal and newborn morbidity, thereby diminishing the long-term quality of life for affected women. Due to the widespread dissatisfaction with the effectiveness of existing approaches for assessing PE risk, there is a pressing need for ongoing research to identify newer, more accurate predictors. This study aimed to investigate early changes in the maternal serum proteome and associated signaling pathways. The levels of 125 maternal serum proteins at 11-13 weeks of gestation were quantified using liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM MS) with the BAK-125 kit. Ten serum proteins emerged as potential early markers for PE: Apolipoprotein M (APOM), Complement C1q subcomponent subunit B (C1QB), Lysozyme (LYZ), Prothrombin (F2), Albumin (ALB), Zinc-alpha-2-glycoprotein (AZGP1), Tenascin-X (TNXB), Alpha-1-antitrypsin (SERPINA1), Attractin (ATRN), and Apolipoprotein A-IV (APOA4). Notably, nine of these proteins have previously been associated with PE in prior research, underscoring the consistency and reliability of our findings. These proteins play key roles in critical molecular processes, including complement and coagulation cascades, platelet activation, and insulin-like growth factor pathways. To improve the early prediction of PE, a highly effective Support Vector Machine (SVM) model was developed, analyzing 19 maternal serum proteins from the first trimester. This model achieved an area under the curve (AUC) of 0.91, with 87% sensitivity and 95% specificity, and a hazard ratio (HR) of 13.5 (4.6-40.8) with p < 0.001. These findings demonstrate that serum protein-based SVM models possess significantly higher predictive power compared to the routine first-trimester screening test, highlighting their superior utility in the early detection and risk stratification of PE.

Potential Predictive Value of Platelet Parameters in Preeclampsia

Objective

Preeclampsia is a serious pregnancy complication that jeopardizes the health of both the mother and the fetus. Platelet parameters are closely linked to the severity of preeclampsia. This study aimed to assess the diagnostic potential of platelet parameters in the early second trimester for the detection of preeclampsia.

Methods

A total of 840 participants from the Affiliated Hospital of Jining Medical College were included in the study, consisting of 327 healthy pregnant women, 209 with mild preeclampsia, and 304 with severe preeclampsia. General clinical data and platelet parameters for these three groups of pregnant women were collected, and differences among them were compared. In addition, univariate analysis and logistic regression were used to identify preeclampsia risk factors, and receiver operating characteristic curve analysis was conducted to assess the predictive value of platelet parameters.

Results

Platelet count was not found to significantly differ between the healthy and preeclampsia groups. However, mean platelet volume, platelet distribution width (PDW), and platelet-large cell ratios (P-LCR) were observed to be significantly higher in the preeclampsia group than the healthy group. After adjusting for confounding factors (such as age, gestational week at blood sampling, systolic and diastolic blood pressure, and body mass index during the second trimester), it was determined that PDW and P-LCR could be considered effective predictors of preeclampsia.

Conclusion

In clinical practice, P-LCR and PDW hold potential predictive value for preeclampsia.

Molecular subclasses of preeclampsia characterized by a longitudinal maternal proteomics study: distinct biomarkers, disease pathways and options for prevention

OBJECTIVES

The heterogeneous nature of preeclampsia is a major obstacle to early screening and prevention, and a molecular taxonomy of disease is needed. We have previously identified four subclasses of preeclampsia based on first-trimester plasma proteomic profiles. Herein, we expanded this approach by using a more comprehensive panel of proteins profiled in longitudinal samples.

METHODS

Proteomic data collected longitudinally from plasma samples of women who developed preeclampsia (n=109) and of controls (n=90) were available from our previous report on 1,125 proteins. Consensus clustering was performed to identify subgroups of patients with preeclampsia based on data from five gestational-age intervals by using select interval-specific features. Demographic, clinical, and proteomic differences among clusters were determined. Differentially abundant proteins were used to identify cluster-specific perturbed KEGG pathways.

RESULTS

Four molecular clusters with different clinical phenotypes were discovered by longitudinal proteomic profiling. Cluster 1 involves metabolic and prothrombotic changes with high rates of early-onset preeclampsia and small-for-gestational-age neonates; Cluster 2 includes maternal anti-fetal rejection mechanisms and recurrent preeclampsia cases; Cluster 3 is associated with extracellular matrix regulation and comprises cases of mostly mild, late-onset preeclampsia; and Cluster 4 is characterized by angiogenic imbalance and a high prevalence of early-onset disease.

CONCLUSIONS

This study is an independent validation and further refining of molecular subclasses of preeclampsia identified by a different proteomic platform and study population. The results lay the groundwork for novel diagnostic and personalized tools of prevention.

Risk factors and foetal growth restriction associated with expectant treatment of early-onset preeclampsia

OBJECTIVE

To identify the factors affecting expectant management of early-onset preeclampsia, and evaluate the correlation between expectant treatment and foetal growth restriction.

MATERIALS AND METHODS

The retrospective study included 72 women who were admitted for early-onset preeclampsia between February 2018 to April 2021. Data included maternal clinical parameters, demographic and maternal and neonatal outcomes, which were analysed for correlation.

RESULTS

Multiple logistic regression analysis demonstrated that the time interval from the onset of 24-h proteinuria to termination of pregnancy showed a strong correlation with the expectant treatment; Univariate logistic analysis confirmed that there was no correlation between expectant treatment and foetal growth restriction.

CONCLUSION

There was a negative correlation between the duration of 24-h proteinuria and the expectant treatment of patients with early-onset preeclampsia; Expectant treatment could not improve the development of foetal growth restriction in patients with early-onset preeclampsia.KEY MESSAGESThe duration of 24-h proteinuria affects the effectiveness of expectant management of early-onset preeclampsia.Expectant management can reduce adverse neonatal outcomes due to iatrogenic preterm delivery, but it cannot improve the occurrence of foetal growth restriction.

Maternal circulating concentrations of soluble Fas and Elabela in early- and late-onset preeclampsia

OBJECTIVE

The Fas/Fas ligand (FASL) system and Elabela-apelin receptor signaling pathways are implicated in the pathophysiology of preeclampsia. The aim of the current study was to investigate whether a model combining the measurement of sFas and Elabela in the maternal circulation may serve as a clinical biomarker for early- and/or late-onset preeclampsia more effectively than measures of each biomarker individually.

METHODS

Blood samples were collected from 214 women in the following groups: (1) normal pregnancy sampled <34 weeks of gestation (n = 56); (2) patients who developed early-onset preeclampsia (n = 54); (3) normal pregnancy sampled ≥34 weeks of gestation (n = 52); (4) patients who developed late-onset preeclampsia (n = 52). Maternal circulating soluble Fas and Elabela concentrations were determined using sensitive and validated immunoassays. Two sample t-tests, multivariate logistic regression, and receiver operating characteristic curves were used for analyses.

RESULTS

(1) Women with early-onset preeclampsia, and those with late-onset preeclampsia with placental lesions of maternal vascular malperfusion, had increased concentrations of sFas compared to their gestational age-matched normal controls; (2) women with late-onset preeclampsia, but not those with early-onset preeclampsia, had increased concentrations of Elabela compared to their gestational age-matched counterparts; and (3) an increase in both Elabela and sFas concentrations was more strongly associated with late-onset preeclampsia than early-onset preeclampsia relative to models including either of the markers alone.

CONCLUSIONS

A combined model of maternal sFas and Elabela concentrations provides a stronger association with late-onset preeclampsia than either protein alone. This finding demonstrates the possibility to improve the classification of late-onset preeclampsia by combining the results of both molecular biomarkers.

Platelet Parameters and Risk of Hypertension disorders of Pregnancy: a Propensity Score Adjusted Analysis

While the role of platelets in cardiovascular diseases among the general population has been widely reported, evidence is inconsistent regarding the association between platelet indices with hypertension in pregnant women. In this study, we explored the associations between platelet parameters before 20 gestational weeks, an understudied period, with hypertensive disorders of pregnancy (HDP), including preeclampsia/eclampsia (PEEC) and gestational hypertension (GH). Based on the Born in Guangzhou Cohort Study, 12053 singleton pregnant women with platelet parameters, including platelet count (PC), mean platelet volume (MPV), plateletcrit (PCT), and platelet distribution width (PDW) measured at 14-19 gestational weeks were included. Conventional multivariable adjustment and propensity score analysis were used to control for confounders. The restricted cubic spline showed that the risk of PEEC increased linearly for PC, and non-linearly for PCT. For GH, the risk increased linearly for PC, MPV, and PCT, and non-linearly for PDW. When these indices were categorized into quintiles, women with higher PC and PCT were associated with increased risk of both PEEC and GH. Women with MPV exceeding the second quintile (≥ 8.8 fL) had a greater risk for GH, but not for PEEC. When HDP was classified into two groups (early- vs late-onset) based on the occurrence time, significant associations persisted for early-onset PEEC, early-onset GH, and late-onset GH. In conclusion, increased PC and PCT before 20 weeks of gestation were both associated with higher risk of PEEC and GH, while elevated MPV was only linked to GH.

Can complete blood count parameters that change according to trimester in pregnancy be used to predict severe preeclampsia?

We aimed to evaluate the effectiveness of changes over time in complete blood count (CBC) parameters to estimate the diagnosis of preeclampsia. Data on 161 severe preeclampsia patients and 161 healthy pregnant patients who met the study criteria of pregnant women whose CBC had been measured at 10-12, 22-24 and 28-30 weeks of pregnancy were compared. In the preeclampsia group, an increase in the mean platelet volume (MPV) value and a decrease in the number of platelets were statistically significant in the transition from the second to the third trimester. MPV and lymphocyte counts were more significant in the third trimester and neutrophil lymphocyte ratio (NLR) were more significant in the second trimester. We found that evaluation of the changes in lymphocyte, MPV and NLR values in three different trimesters of pregnancy rather than a single trimester was more meaningful to predict severe preeclampsia.Impact StatementWhat is already known on this subject? Studies have shown that MPV and NLR can predict preeclampsia. However, a clear cut off value could not be determined. The reasons for this may be that the gestational week during which the measurement is made is not standard and the patient groups are not homogeneous.What the results of this study add? In this study, CBC parameters at different stages of the preeclampsia process were compared in the severe preeclampsia group. According to our results, lymphocytes, NLR and MPV can be used to predict severe preeclampsia. In addition, NLR measurements in the second trimester and MPV and lymphocyte measurements in the third trimester were found to be more significant in predicting severe preeclampsia.What the implications are of these findings for clinical practice and/or further research? In order to predict severe preeclampsia, instead of a single measurement of CBC parameters, new calculations should be made that add change over time.

Pathophysiology of the Venous Thromboembolism Risk in Preeclampsia

Preeclampsia complicates up to 8% of pregnancies and is a leading cause of fetomaternal morbidity andmortality. Treatment options are limited, with supportive care and delivery of the placenta representing the cornerstone of current management strategies. Derangements in blood coagulation are wellrecognised in this disorder and appear to favour an increased risk of venous thromboembolism among affected women. This risk appears to be most significant in the postpartum period. The mechanisms underlying this increased thrombosis risk remain to be fully elucidated although increased expression of procoagulant factors, endothelial dysfunction, attenuation of endogenous anticoagulant activity and increased platelet activity have been implicated in the prothrombotic tendency. Preeclampsia is also occasionally complicated by life-threatening haemorrhagic events and current evidence suggests that in some severe manifestations of this disease a coagulopathy with a clinical bleeding tendency may be the predominant haemostatic abnormality. Identifying affected women at significant risk of thrombosis and managing the competing thrombotic and haemorrhagic risks continue to be a significant clinical challenge. Derangements in blood coagulation are also implicated in the pathogenesis of preeclampsia; however, the role of antiplatelet or anticoagulant drugs in the prevention and treatment of this disorder remains a source of considerable debate. In addition, the potential role of specific haemostatic markers as diagnostic or screening tools for preeclampsia has also yet to be determined. Further characterisation of the underlying molecular mechanisms would likely be of major translational relevance and could provide insights into the pathogenesis of this disease as well as the associated haemostatic dysfunction.

Alterations of Several Serum Parameters Are Associated with Preeclampsia and May Be Potential Markers for the Assessment of PE Severity

The precise pathophysiological mechanisms of preeclampsia (PE) and preventative strategies remain unknown. Laboratory markers which can help in identifying PE patients from pregnant women and assessing the severity of PE during pregnancy are worthy to be explored. In this study, a retrospective case-control study was designed to assess whether the serum levels of albumin (ALB), total protein (TP), prealbumin (PA), alkaline phosphatase (ALP), lactic dehydrogenase (LDH), D-dimer, fibrinogen (Fbg), platelet (PLT) count, mean platelet volume (MPV), and platelet distribution width (PDW) can help in assessing PE and evaluate its severity. 256 pregnant women were enrolled and classified into 3 groups: mild preeclampsia (mPE, n = 85), severe preeclampsia (sPE, n = 78), and healthy normotensive controls (control, n = 93). Our result showed that the serum levels of ALP, LDH, and D-dimer were significantly higher in mild or severe PE patients compared with the healthy controls (66 (52.5-76.5) vs. 168 (141.5-201.25) vs. 182.5 (120-191.5), 152 (139.75-166.25) vs. 183.5 (163.25-307) vs. 282 (215.25-306), 1.05 (0.65-1.57) vs. 3.05 (2.25-4.08) vs. 5.65 (2.29-7.71)), while ALB, TP, and PA are lower (38 (37-42) vs. 31.5 (25.5-34.5) vs. 28.5 (24-33), 65 (63-68.25) vs. 56.5 (52-61) vs. 51.5 (49-58), 219.14 ± 68.25 vs. 167.88 ± 52.21 vs. 143.22 ± 50.46). On the other hand, compared with the mPE group, the sPE group showed significantly lower PLT count but higher level of LDH, D-dimer, and Fbg. No significant differences in MPV or PDW were found between any of the two groups. In conclusion, the above markers except for the MPV and PDW may be correlated with PE severity in this patient cohort, indicating possible values of these potential biomarkers in auxiliary diagnosis and severity assessment of PE.

Comparison of mean platelet volume (MPV) and sFlt-1/PlGF ratio as predictive markers for preeclampsia

INTRODUCTION

Preeclampsia is characterised by an increased platelet consumption with consecutive reduction of overall platelet count and a consecutive rise in mean platelet volume (MPV). MPV has therefore been suggested as a predictive marker for preeclampsia. We aimed to investigate MPV longitudinally in women with preeclampsia compared to healthy controls during pregnancy for potential early detection of preeclampsia and to compare potential MPV changes against the sFlt-1/PlGF ratio.

STUDY DESIGN

This longitudinal study included 38 women with preeclampsia and 84 women with normal pregnancies, where MPV and sFlt-1 and PLGF levels were determined every 4 weeks, starting in early pregnancy.

RESULTS

MPV was significantly higher in women who developed preeclampsia compared to women with normal pregnancies at 12, (p = .029), 24 (p = .011), 28 (p = .037), 32 (p = .002), and 36 weeks of gestation, respectively (p = .015). Further analysis revealed a cut-off point of 10.85 fl (sensitivity 65.6%, specificity 26.2%) for the prediction of preeclampsia. The sFlt-1/PlGF ratio was significantly higher in women who developed preeclampsia compared to women with normal pregnancies at the same time points (p = .001). The cut-off point for predicting preeclampsia was 10.3 (sensitivity 87.5%, specificity 11.9%). ROC curve analysis showed that MPV has a high predictive value for early-onset preeclampsia (p < .05) but not for late-onset preeclampsia.

CONCLUSION

MPV is significantly elevated even in early pregnancy in women who develop preeclampsia and seems, therefore, a valuable predictor for preeclampsia even at early gestation. However, according to our results, MPV seems reliable in predicting early onset preeclampsia.

First trimester complete blood cell indices in early and late onset preeclampsia

Objective

This study aimed to compare the first trimester complete blood count (CBC) indices of pregnancies complicated by early-onset preeclampsia (EOPE) or late-onset preeclampsia (LOPE).

Material and Methods

A retrospective case-control study was conducted with 186 patients. Patients were classified into three subgroups: EOPE, LOPE, and control groups. First trimester CBC results were obtained for each patient. Hemoglobin, hematocrit, red blood cell distribution width, mean corpuscular volume, white blood cell (WBC) count, neutrophil, eosinophil, basophil, lymphocyte, monocyte, mean platelet volume, platelet distribution width, plateletcrit, and platelet count were compared. The neutrophil lymphocyte ratio was calculated by dividing the absolute lymphocyte count by the absolute neutrophil count. The platelet lymphocyte ratio was calculated by dividing the absolute lymphocyte count by the absolute platelet count.

Results

The total number of cases was 21, 42, and 123, in the EOPE, LOPE, and control groups, respectively. There were statistically significant differences in the total WBC and neutrophil counts between the three groups (both p<0.05). WBC and neutrophil counts were found to be highest in the EOPE group, and the LOPE group had higher levels compared with controls. The optimal cut-off values to predict EOPE for WBC and neutrophil counts were 9.55×10³/ μL (sensitivity 71.4% and specificity 70.7%) and 6.45×10³/μL (sensitivity 66.7% and specificity 74.8%), respectively.

Conclusion

Increased first trimester WBC and neutrophil counts may be predictive for EOPE.