Maternal platelet-to-lymphocyte ratio at delivery can predict poor neonatal outcome in preterm births

Relationship between Platelet-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio with Spontaneous Preterm Birth: A Systematic Review and Meta-analysis

Background

Spontaneous preterm birth is one of the most common pregnancy complications in obstetric clinical practice, and its etiology is complex. The problems of low survival and high morbidity rates of premature infants need to be solved urgently. The platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) are two novel biomarkers of inflammation, and several studies have linked PLR and LMR to spontaneous preterm birth. These systematic review and meta-analysis are aimed at analyzing the relationship between PLR and LMR in patients with spontaneous preterm birth to provide new ideas for the early prevention and treatment of spontaneous preterm births.

Methods

Cochrane Library, EMBASE, PubMed, and China National Knowledge Infrastructure databases were inspected to gather PLR and LMR in patients with spontaneous preterm birth, all from the database to February 2022. Interstudy heterogeneity was evaluated using Cochran's Q test and I 2 statistic. Differences in PLR and LMR between patients with spontaneous preterm birth and full-term controls were evaluated by computing standardized mean differences and 95% confidence intervals. Publication bias and sensitivity analyses were also performed.

Results

Nine studies were included in the meta-analysis based on the inclusion and exclusion criteria. The meta-analysis showed that serum PLR values were remarkably larger for patients with spontaneous preterm birth than for full-term controls (SMD = 0.49, 95% CI: 0.13 to 0.84, P = 0.007), whereas the difference between serum LMR in patients with spontaneous preterm birth and full-term controls was not statistically significant (SMD: 0.35, 95% CI: -0.18, 0.88, P = 0.199). The results of Begg's and Egger's tests revealed that the publication bias of the meta-analysis was not significant. The outcomes of the sensitivity analysis showed that the individual studies did not influence the meta-analysis results.

Conclusions

Current evidence shows that PLR is strongly associated with spontaneous preterm birth, whereas LMR is not. PLR has a certain clinical value in diagnosing and treating spontaneous preterm births, and our research will provide strong theoretical support for clinical work. In the future, it will be necessary to further explore the reasons for the increased PLR in the serum of patients with spontaneous preterm birth and other mechanisms inducing spontaneous preterm birth.

Role of derived neutrophil-to-lymphocyte ratio, uric acid-to-creatinine ratio and Delta neutrophil index for predicting neonatal outcomes in pregnancies with preeclampsia

We aimed to compare the maternal and neonatal systemic inflammatory markers, platelet indices and new indices in biochemical parameters in women with preeclampsia and healthy controls. The secondary aim was to investigate whether there was a relationship between maternal hematological markers and neonatal outcomes. A retrospective case control study was conducted in a tertiary hospital. Maternal demographic and birth characteristics, complete blood count indices, derived neutrophil to lymphocyte ratio (dNLR), Delta neutrophil index (DNI), uric acid-to-creatinine (Cre) ratio and uric acid-to-alanine transaminase ratio, neonatal hematological parameters were compared between the preeclamptic group and control group. The study consisted of 170 cases (84 preeclampsia and 86 control). Neutrophil-to-lymphocyte ratio (NLR), dNLR, blood urea nitrogen (BUN), creatinine (Cre), uric acid, LDH, aspartate transaminase (AST) and alanine aminotransferase (ALT), uric acid-to-Cre ratio and uric acid-to-ALT ratio were higher and statistically significant in the preeclamptic group than in control ones (p: 0.000 - BUN, Cre, uric acid, LDH, p: 0.001 - AST, p: 0.004 - ALT, p: 0.000 - uric acid-to-Cre ratio, p: 0.009 - uric acid-to-ALT ratio, respectively). NLR and platelet-to-lymphocyte (PLR) ratio were significantly higher in newborns of preeclamptic mothers (p: 0.039; p: 0.004, respectively). A low-moderate correlation between maternal uric acid-to-Cre ratio and neonatal PLR was detected (r: 0.193; p: 0.013). Moreover, moderate negative correlations between maternal PLR (r:-0.231, p: 0.002), uric acid (r: 0.332, p:0.000) and adverse neonatal outcomes were found. Uric acid and PLR, which can be easily calculated clinically may predict adverse neonatal outcomes.IMPACT STATEMENTWhat is already known about this topic? Preeclampsia is known as a significant cause of maternal morbidity and mortality. Haematological indices have been evaluated for the prognosis of many kinds of disease.What do the results of this study add? This study has focussed on new combined haematological-biochemical indices and its relationship with neonatal outcomes. Both higher NLR, derived NLR, DNI and lower PLR were recorded as useful markers for preeclampsia.What are the implications of these findings for clinical practice and/or further research? Some indices that were calculated by assessing basic and simple blood parameters may help clinicians to predict clinical outcomes of preeclampsia.

Can Inflammatory Hematological Parameters be a Guide to Late-onset Fetal Growth Restriction?

PURPOSE

To compare the rates obtained from hematological parameters in cases of late-onset idiopathic fetal growth restriction (FGR) with healthy pregnancies and to evaluate the effect on neonatal outcomes.

METHODS

The study group consisted of 63 pregnant women with late-onset idiopathic FGR and the control group consisted of 91 healthy pregnant women. The determined rates were calculated from the control hemograms of patients at 28 weeks. Both groups were compared for neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and other parameters.

RESULTS

NLR, leukocyte and neutrophil levels were significantly higher in the FGR group (p<0.05). There was no significant difference in PLR, platelet and lymphocyte levels between the groups (p>0.05). To predict FGR, the best cut-off value of NLR was determined to be 4.11 with 56% sensitivity and 88% specificity values.

CONCLUSION

Neutrophil, lymphocyte and platelet interactions have an important role in FGR development. Inflammation can be involved in the etiopathogenesis in late-onset FGR.

Correlation of biological parameters with placental parameters and pregnancy outcomes in pre-eclamptic women

INTRODUCTION

Pre-eclampsia is characterized by maternal vascular malperfusion and chronic inflammation in placenta. Our purpose was to investigate the potential correlation of biological parameters with placental parameters and pregnancy outcomes in pre-eclamptic women.

METHODS

Pre-eclamptic women were identified by interrogation of the Medical Registry Department in six French maternities between April 2013 and June 2018. Histological parameters in placentas (weight, macroscopic and microscopic lesions), baseline maternal characteristics and pregnancy outcomes (course of pregnancy, newborns' characteristics) were collected. Biological parameters were blood cell ratios (Platelet-to-Lymphocyte Ratio (PLR), Neutrophil-to-Lymphocyte Ratio (NLR)) collected at delivery and Placental growth factor (PlGF) measured in women with an available first trimester serum sample. Correlations of blood cell ratios and PlGF levels with placental parameters and pregnancy outcomes were assessed by Pearson's correlation test for quantitative parameters and by logistic regression analysis for qualitative parameters.

RESULTS

202 pregnancies were included, among which 68 had a first trimester PlGF quantification. No correlation was found between biological parameters and placental lesions. Low PLR was correlated with low placental weight (r = 0.156, p = 0.036) and with low birth weight (r = 0.179, p = 0.015). Low PlGF was correlated with long time from pre-eclampsia diagnosis to delivery (r = -0.250, p = 0.048).

CONCLUSIONS

There is no correlation between biological parameters and placental lesions in pre-eclamptic women. Yet, low PLR at delivery is correlated with low placental and birth weights. Moreover, low first trimester PlGF is correlated with long time from pre-eclampsia diagnosis to delivery.