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

Clinical value of mean platelet volume in predicting and diagnosing pre-eclampsia: a systematic review and meta-analysis

Background

Pre-eclampsia (PE) is a severe pregnancy complication. Thrombocytopenia and platelet dysfunction are common hematology disorders in PE. Previous studies considered mean platelet volume (MPV), a functional marker of platelets, as a potentially useful predictor for the diagnosis of PE.

Methods

PubMed, China Biomedical Literature Database, Chinese National Knowledge Infrastructure, Embase, Wanfang, VIP, and Cochrane Library databases were searched to gather diagnostic trials evaluating the diagnosis of PE using MPV, from their inception to 13 March 2023. We also searched Google Scholar and Baidu.

Results

A total of 22 studies from 20 articles were found. The pooled diagnostic accuracy of the MPV for PE recognition was as follows: sensitivity (SEN) 0.676 [95% confidence interval (CI) (0.658-0.694)], specificity (SPE) 0.710 [95% CI (0.703-0.717)], and diagnostic odds ratio (DOR) 7.012 [95% CI (4.226-11.636)], and the SROC-AUC and Q* indices were 0.7889 and 0.7262, respectively. The pooled SEN, SPE, and DOR of the diagnostic accuracy of MPV for PE before 16 weeks of gestation were 0.707 [95% CI (0.670-0.743)], 0.639 [95% CI (0.611-0.667)], and 4.026 [95% CI (2.727-5.943)], and the SROC-AUC and Q* indices were 0.7278 and 0.6753, respectively. For the interval of truncation values between 9 and 10 fl, the SROC-AUC and Q* indices for MPV were 0.8856 and 0.8162, respectively.

Conclusions

Available evidence suggests that MPV has a moderate predictive and diagnostic value for PE, particularly in diagnosing after 20 weeks of gestation. The diagnostic accuracy is higher when the MPV cut-off falls between 9 and 10 fl. The sensitivity of MPV alone in diagnosing PE is not high, and the combination of other markers for predictive diagnosis may better differentiate PE.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023425154, identifier: CRD42023425154.

Incremental predictive value of platelet parameters for preeclampsia: results from a large prospective cohort study

BACKGROUND

Platelet parameters during pregnancy were associated with the risk of preeclampsia (PE), but the predictive value of these parameters for PE remained unclear. Our aim was to clarify the individual and incremental predictive value of platelet parameters, including platelet count (PC), mean platelet volume (MPV), plateletcrit (PCT), and platelet distribution width (PDW) for PE.

METHODS

This study was based on the Born in Guangzhou Cohort Study in China. Data on platelet parameters were extracted from medical records of routine prenatal examinations. Receiver operating characteristic (ROC) curve was performed to analyze the predictive ability of platelet parameters for PE. Maternal characteristic factors proposed by NICE and ACOG were used to develop the base model. Detection rate (DR), integrated discrimination improvement (IDI) and continuous net reclassification improvement (NRI) were calculated compared with the base model to assess the incremental predictive value of platelet parameters.

RESULTS

A total of 30,401 pregnancies were included in this study, of which 376 (1.24%) were diagnosed with PE. Higher levels of PC and PCT were observed at 12-19 gestational weeks in women who developed PE later. However, no platelet parameters before 20 weeks of gestation reliably distinguished between PE complicated pregnancy and non-PE complicated pregnancy, with all values of the areas under the ROC curves (AUC) below 0.70. The addition of platelet parameters at 16-19 gestational weeks to the base model increased the DR for preterm PE from 22.9 to 31.4% at a fixed false positive rate of 5%, improved the AUC from 0.775 to 0.849 (p = 0.015), and yielded a NRI of 0.793 (p < 0.001), and an IDI of 0.0069 (p = 0.035). Less but significant improvement in prediction performance was also observed for term PE and total PE when all the four platelet parameters were added to the base model.

CONCLUSIONS

Although no single platelet parameter at the early stage of pregnancy identified PE with high accuracy, the addition of platelet parameters to known independent risk factors could improve the prediction of PE.

Preeclampsia has an association with both platelet count and mean platelet volume: A systematic review and meta-analysis

Background

Preeclampsia (PE) is a pregnancy-specific disorder characterized by endothelial dysfunction, and activation of the coagulation system. Alteration of PLT parameters is the common hematological abnormality observed in women with PE. The main aim of this study was to systematically review previous studies from around the world to generate evidence about the relationship between platelet count (PC) and PE, as well as mean platelet volume (MPV) and PE, by calculating the pooled weighted mean difference (WMD) of PC and MPV between PE and normotensive (NT) groups.

Methods

Relevant articles which were published in the English language from January 10, 2011, to January 10, 2021, were systematically searched through PubMed, Web of Science, and African journals online. In addition, reference probing of published articles searching was employed through Google Scholar and Google for searching grey literature. The methodological qualities of articles were assessed using Joana Brigg’s institute critical appraisal checklist. A random-effects model was used to estimate pooled WMD of PLT parameters between the two groups with the respective 95% confidence intervals (CI) using Stata version 11.0. The I2 statistics and Egger’s regression test were used to assess heterogeneity and publication bias among included studies, respectively.

Results

A total of 25 articles were included in this systematic review and meta-analysis. Of which, 23 studies were used in each PC and MPV analysis. The overall pooled WMD of PC and MPV between PE and NT groups were -41.45 × 109/L [95% CI; -51.8, -31.0] and 0.98 fl [95% CI; 0.8, 1.1], respectively. The pooled WMD revealed that PC decreased significantly in the PE group compared to the NT group while MPV increased significantly in the PE group.

Conclusions

This systematic review and meta-analysis indicated that there is a significant decrease in PC and a significant increase in MPV during PE development among pregnant women. As a result, a change in these parameters among pregnant women may indicate the development of PE.

Study of the effect of acetylsalicylic acid and a selective arginase II inhibitor KUD 975 on the correction of hemostatic disorders in experimental preeclampsia

Introduction: The disruption of the functional state of the vascular endothelium is among the main causes of preeclampsia, which is one of the most common causes of maternal and perinatal mortality. It can be enhanced by the humoral factors secreted by the activated platelets. The use of acetylsalicylic acid is an effective way to prevent preeclampsia. However, its ability to activate eNOS is a prerequisite for researching its ability to correct the disorders in developing preeclampsia, including by reducing the platelet activity. In this case its effect can be enhanced through increasing the bioavailability of L-arginine by using a selective arginase II inhibitor KUD 975. These facts were the prerequisite for conducting this study.

Materials and methods: The study was conducted on 180 female Wistar rats weighing 250–300 g. Acetylsalicylic acid was used at a dose of 7 mg/kg/day and 10 mg/kg/day, KUD 975 – at a dose of 1 mg/kg/day and 3 mg/kg/day. Adenosine diphosphate (ADP, 6.5 microns), arachidonic acid (ASPI, 0.5 mM), and collagen (3.2 mcg/ml) were used as aggregation inducers.

Results and discussion: ADMA-like preeclampsia simulation led to an increase in platelet aggregation ability when using all aggregation inducers. This is evidenced by an increase in a degree, rate of aggregation, and a shortened time of thrombus formation. The use of acetylsalicylic acid and a selective arginase II inhibitor KUD 975 led to a decrease in the aggregation ability of platelets and an increase in thrombosis time, while the combined administration of the studied agents showed a more pronounced effect.

Conclusion: The data obtained while performing a series of experiments strongly indicate a promising outlook for using acetylsalicylic acid and a selective arginase II inhibitor KUD 975 in order to correct emerging disorders in preeclampsia.

A New Model for the Predicting the Risk of Preeclampsia in Twin Pregnancy

Objective

We aimed to develop an effective nomogram model for predicting the risk of preeclampsia in twin pregnancies.

Methods

The study was a retrospective cohort study of women pregnant with twins who attended antenatal care and labored between January 2015 and December 2020 at the Fujian Maternity and Child Health Hospital, China. We extracted maternal demographic data and clinical characteristics. Then we performed the least absolute shrinkage and selection operator regression combined with clinical significance to screen variables. Thereafter, multivariate logistic regression was used to construct a nomogram that predicted the risk of preeclampsia in twin pregnancies. Finally, the nomogram was validated using C-statistics (C-index) and calibration curves.

Results

A total of 2,469 women with twin pregnancies were included, of whom 325 (13.16%) had preeclampsia. Multivariate logistic regression models revealed that serum creatinine, uric acid, mean platelet volume, high-density lipoprotein, lactate dehydrogenase, fibrinogen, primiparity, pre-pregnancy body mass index, and regular prenatal were independently associated with preeclampsia in twin pregnancies. The constructed predictive model exhibited a good discrimination and predictive ability for preeclampsia in twin pregnancies (concordance index 0.821).

Conclusion

The model for the prediction of preeclampsia in twin pregnancies has high accuracy and specificity. It can be used to assess the risk of preeclampsia in twin pregnancies.

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 Changes in Pregnancies with Severe Early Fetal Intrauterine Growth Restriction

Background and Objectives: In this study, we investigated the changes of platelet count and other platelet indices, such as mean platelet volume (MPV), in cases with severe early intrauterine fetal growth restriction (IUGR). Materials and Methods: We retrospectively analyzed all pregnancies diagnosed with severe early onset IUGR, that were followed up in our hospital between 2010 and 2015 (before implementation of screening and prophylaxis with aspirin). Pregnancies which resulted in birth of a newborn with a birthweight less than 5th percentile for gestational age, that required delivery for fetal or maternal indication before 32 weeks, were selected for the IUGR group. The IUGR cases were divided into two groups according to preeclampsia (PE) association. All cases with a complete blood count (CBC) performed within 7 days prior to delivery were included in the study, as the IUGR group. The control group included normal singleton pregnancies, delivered at term, with birthweight above 10th centile and a CBC taken at 30–32 weeks. Results: There was a significant difference in platelet count and MPV values between the IUGR group and control. Cases with IUGR presented lower platelet count and higher MPV values; there was no significant difference of these parameters when PE was associated with IUGR. Conclusions: Our results suggest that in cases of severe early IUGR, even in the absence of clinically diagnosed PE, there may be maternal endothelial damage and platelet consumption in the systemic and uteroplacental circulation. Platelet count and MPV values are simple and widely available laboratory tests that might be used as indicator of placental insufficiency; however, prospective data are required to establish the mechanistic link and to which extent these parameters are good predictors of severity or adverse perinatal outcomes.

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.

Maternal Platelets—Friend or Foe of the Human Placenta?

Human pregnancy relies on hemochorial placentation, including implantation of the blastocyst and deep invasion of fetal trophoblast cells into maternal uterine blood vessels, enabling direct contact of maternal blood with placental villi. Hemochorial placentation requires fast and reliable hemostasis to guarantee survival of the mother, but also for the neonates. During human pregnancy, maternal platelet count decreases gradually from first, to second, and third trimester. In addition to hemodilution, accelerated platelet sequestration and consumption in the placental circulation may contribute to a decline of platelet count throughout gestation. Local stasis, turbulences, or damage of the syncytiotrophoblast layer can activate maternal platelets within the placental intervillous space and result in formation of fibrin-type fibrinoid. Perivillous fibrinoid is a regular constituent of the normal placenta which is considered to be an important regulator of intervillous hemodynamics, as well as having a role in shaping the developing villous trees. However, exaggerated activation of platelets at the maternal-fetal interface can provoke inflammasome activation in the placental trophoblast, and enhance formation of circulating platelet-monocyte aggregates, resulting in sterile inflammation of the placenta and a systemic inflammatory response in the mother. Hence, the degree of activation determines whether maternal platelets are a friend or foe of the human placenta. Exaggerated activation of maternal platelets can either directly cause or propagate the disease process in placenta-associated pregnancy pathologies, such as preeclampsia.