Polymorphism in the tumor necrosis factor-alpha gene in women with preeclampsia

Polymorphisms within the Tumor Necrosis Factor-Alpha Gene Is Associated with Preeclampsia in Taiwanese Han Populations

Preeclampsia (PE) occurs in women pregnant for more than 20 weeks with de novo hypertension and proteinuria, and is a devastating disease in maternal–fetal medicine. Cytokine tumor necrosis factor (TNF)-α may play a key role in the pathogenesis of PE. We conducted this study to investigate the regulatory regions of the TNF genes, by investigating two promoter polymorphisms, TNFA-308G/A (rs1800629) and -238G/A (rs361525), known to influence TNF expression, and their relationship to PE. An observational, monocentric, case–control study was conducted. We retrospectively collected 74 cases of severe PE and 119 pregnant women without PE as control. Polymerase chain reaction (PCR) was carried out for allele analysis. Higher A allele in women with PE was found in rs1800629 but not rs361525. In this study, we first found that polymorphism at the position -308, but not -238, in the promoter region of the TNF-α gene can contribute to severe PE in Taiwanese Han populations. The results of our study are totally different to previous Iranian studies, but have some similarity to a previous UK study. Further studies are required to confirm the roles of rs1800629 and rs361525 in PE with circulating TNF-α in PE.

Pregnancy, preeclampsia and maternal aging: From epidemiology to functional genomics

Women live longer than men but experience greater disability and a longer period of illness as they age. Despite clear sex differences in aging, the impact of pregnancy and its complications, such as preeclampsia, on aging is an underexplored area of geroscience. This review summarizes our current knowledge about the complex links between pregnancy and age-related diseases, including evidence from epidemiology, clinical research, and genetics. We discuss the relationship between normal and pathological pregnancy and maternal aging, using preeclampsia as a primary example. We review the results of human genetics studies of preeclampsia, including genome wide association studies (GWAS), and attempted to catalog genes involved in preeclampsia as a gateway to mechanisms underlying an increased risk of later life cardio- and neuro- vascular events. Lastly, we discuss challenges in interpreting the GWAS of preeclampsia and provide a functional genomics framework for future research needed to fully realize the promise of GWAS in identifying targets for geroprotective prevention and therapeutics against preeclampsia.

Contribution of -1031T/C and -376G/A tumor necrosis factor alpha polymorphisms and haplotypes to preeclampsia risk in Tunisia (North Africa)

Preeclampsia is a gestational disorder characterized by hypertension and proteinuria. Excessive release of pro-inflammatory cytokines, particularly tumour necrosis factor-alpha, has been demonstrated to contribute to endothelial activation and poor trophoblast invasion in placental development, resulting in preeclampsia's clinical symptoms. Genetic polymorphisms of tumour necrosis factor-alpha can regulate its production and may play an important role in the pathogenesis of this disease. This study aimed to evaluate the association of five tumour necrosis factor-alpha gene promoter single nucleotide polymorphisms, or their haplotype combinations, with preeclampsia prevalence. This case-control study was conducted on 300 women with preeclampsia and 300 age-matched women with normal pregnancy from Tunisian hospitals. Genotyping of tumour necrosis factor-alpha -1031 T/C, -376 G/A, -308 G/A, -238 G/A, and +489 G/A SNPs was performed on DNA extracted from blood samples using PCR-restriction fragment-length polymorphism analysis. Statistical analysis was performed using the chi-square test. P < 0.01 were considered statistically significant to take into consideration the multiple comparisons. A significantly higher frequency of the minor allele -1031C (p < 0.001) was observed in preeclampsia cases compared to controls. Notably, the -1031C and -376A (CA) haplotype, which correlates with a higher production of TNF-α protein, had a higher incidence in women with preeclampsia (p = 0.0005). Conversely, the TG haplotype had a low frequency in preeclampsia cases compared to controls (p = 0.002) which suggests that it is associated with a reduced incidence of preeclampsia. These results suggest that tumour necrosis factor-alpha polymorphisms, in particular the -1031C/A, and the haplotype CA, contribute to an increased risk of preeclampsia in Tunisian women.

Tumour necrosis factor-α (TNF-α) serum levels in preeclampsia pregnant women and pregnant women at risk with preeclampsia

OBJECTIVE

This study aimed to determine serum tumour necrosis factor-α (TNF-α) levels in pregnant women with the risk of preeclampsia and those who have preeclampsia.

METHOD

This research was a cross-sectional study and conducted in two maternal and child hospitals in Makassar, South Sulawesi, Indonesia, that is Pertiwi and Fatimah hospitals. As many as 86 pregnant women; 31 normal blood pressure, 26 high-risk preeclampsia and 29 preeclampsia pregnant women checked their blood pressure and then gave informed consent. TNF-α level was examined used enzyme-linked immunosorbent assay (ELISA) in Hasanuddin University laboratorium. Pregnant women with antiplatelet therapy, infectious, and inflammatory diseases were excluded from the study. Data presented in the form of tables and narratives. The bivariate analysis presented in the form of a cross table between variables TNF-α levels with pregnant women at risk for preeclampsia and preeclampsia and analyzed used Kruskal Wallis Test.

RESULTS

TNF-α levels in normal patients are 24.47pg/ml, whereas those at the risk of preeclampsia appear two times higher than preeclampsia (57.052pg/ml), pregnant women with preeclampsia have approximately five times higher levels than normal pregnant women (327.330pg/ml).

CONCLUSION

Increased levels of TNF have begun to occur during the high-risk phase and have increased very high during preeclampsia.

Association between tumor necrosis factor-α-308G/A gene polymorphism and susceptibility to pre-eclampsia: An updated meta-analysis

AIMS

Although two meta-analysis have reported no association between the tumor necrosis factor-α (TNF-α)-308G/A polymorphism and susceptibility to pre-eclampsia (PE), recent studies showed the association was still controversial. Thus, we conduct an updated meta-analysis to elucidate this association.

METHODS

Studies related to TNF-α-308G/A and PE risk were retrieved from PubMed, the Web of Science, Embase, Cochrane Library, CNKI, Wanfang, CBM, VIP Database. The odds ratios (OR) and 95% confidence intervals (CIs) were calculated to estimate the association between the TNF-α-308G/A polymorphism and susceptibility to PE under the models of allelic contrast (A vs. G), recessive (AA vs. AG+GG), dominant (AA+AG vs. GG), and co-dominant (AA vs. GG).

RESULTS

22 studies (including 2459 cases and 4246 controls) were included in the meta-analysis. The overall analysis indicated that the significant association between TNF-α-308G/A polymorphism and susceptibility to pre-eclampsia existed in allele model (A vs. G: OR = 1.37, 95%CI: 1.06-1.77), but not in dominant model, recessive model, and co-dominant model. In subgroup analysis by ethnicity, pre-pregnancy BMI and pregnancy parity, the results showed the significant association between TNF-α-308G/A polymorphism and the risk of PE was obvious in Caucasian (A vs. G: OR = 1.36, 95%CI: 1.13-1.64; AA vs. GG: OR = 1.71, 95%CI: 1.03-2.86; AA+AG vs. GG: OR = 1.32, 95%CI: 1.03-1.71), Iranian (A vs. G: OR = 4.28, 95%CI: 2.01-9.11), and primipara (A vs. G: OR = 1.49, 95%CI: 1.15-1.92; AA vs. GG: OR = 2.15, 95%CI: 1.10-4.21).

CONCLUSION

Current evidence demonstrates that carriers of TNF-α (308A) allele would increase the susceptibility to PE, especially among Caucasian, Iranian and primipara.

Candidate Gene, Genome-Wide Association and Bioinformatic Studies in Pre-eclampsia: a Review

PURPOSE OF REVIEW

Regardless of the familial linkage reported in pre-eclampsia development, understanding the polymorphic genes associated with pre-eclampsia remains limited. Hence, this review aims to outline the main genetic factors that have been investigated in respect to pre-eclampsia development.

RECENT FINDINGS

It is apparent that different genes show significance in varying populations. Notably, it is reported that apolipoprotein-1 gene polymorphisms are associated with pre-eclampsia development in an African-American population, which may be worthwhile to investigate in a Black South African cohort. Despite the research attention that is focused on this surreptitious syndrome, a definitive cause eludes scientists and physicians, alike. Genetic studies can fulfil a dual purpose of suggesting novel hypotheses through genome-wide screening and testing these hypotheses via candidate gene studies. However, publications to date have only presented inconsistent and conflicting results regarding candidate gene analysis.

CD14 Receptor Gene Promoter Polymorphism: Awakening Maternal Immunity during Pregnancy

We investigated whether monocyte CD14 receptor gene promoter polymorphisms were associated with the development and severity of pre-eclampsia. We genotyped the CD14-260 C/T polymorphism in 36 preeclamptic patients and 52 healthy pregnant controls. A total of 30.6% and 69.4% of pre-eclamptic patients had the C and T alleles, respectively, and 48.0% and 52.0% of the controls, respectively. More pre-eclamptic patients were TT homozygotes compared with controls (50.0% versus 13.5%). In pre-eclamptic patients, the TT homozygotes exhibited a significantly higher mean systolic blood pressure compared with the non-TT homozygotes (173 ± 28 mmHg versus 153 ± 22 mmHg). We also noted a tendency towards increased proteinuria and placental abruption in the TT homozygotes compared with the non-TT homozygotes. We conclude that CD14 gene promoter polymorphisms appear to be a risk factor for pre-eclampsia. With further research, these findings might form the basis of a prognostic tool for pre-eclampsia.

Recent insights into the pathophysiology of preeclampsia

Preeclampsia, characterized by new-onset gestational hypertension and proteinuria, is a common and serious complication of pregnancy. Evidence from both animal and human studies has implicated placental ischemia and hypoxia as a central causative factor in the etiology of the disorder. The ischemic placenta in turn initiates a cascade of secondary effector mechanisms, including altered proangiogenic and antiangiogenic factor balance, increase in maternal oxidative stress and endothelial and immunological dysfunction. The full elucidation of these mechanisms will hopefully lead to a more complete understanding of the etiology of preeclampsia and lead to successful therapeutic intervention through the targeted disruption of new and novel pathways.

Tumor necrosis factor-alpha polymorphism at position -238 in preeclampsia

Background:

Preeclampsia is the most common serious disorder during pregnancy and studies show several immune-related processes in its pathophysiology. The role of cytokines and their expression remains controversial in this field. One of the cytokines of interest in recent studies has been TNF-α, which has been shown to have a higher level in maternal plasma of preeclamptic women.

Objectives:

This study was designed to evaluate the role of TNF-α polymorphism at position -238 in the risk of developing preeclampsia during pregnancy.

Patients and Methods:

One hundred fifty three preeclamptic cases and 140 healthy pregnant women were retrieved from two major hospitals of Mashhad, Iran. Methods a case-control study were designed. Anyone with a history of inflammatory disease, hypertension, or chronic kidney disease was excluded. DNA was extracted from peripheral blood leukocytes. Both groups were genotyped for the polymorphism of the TNF-α gene at position -238 by the RFLP method with Ava II enzyme. Allele and genotype frequencies were compared using one-way ANOVA and the Fisher’s exact test.

Results:

There were significant differences between the two groups in TNF-α genotype at position -238 (P < 0.001). In the preeclamptic group, the frequency of the AA genotype was higher (P < 0.001) and the frequency of the GG genotype was lower (P < 0.001). The overall prevalence of the A allele at position -238 was higher in preeclamptic cases (P < 0.001).

Conclusion:

In this study group, TNF-α -238 polymorphism was shown to be different in preeclamptic and non-preeclamptic pregnant women. The AA genotype and the A allele may carry an increased risk for developing of preeclampsia.

Effect of intravenous hydralazine infusion on maternal plasma nitric oxide levels in gestations complicated with severe preeclampsia: a pilot study

AIM

To investigate the effect of intravenous hydralazine infusion on maternal nitric oxide (NO) levels.

METHODS

This pilot study comprised 40 (n = 40) gestations complicated with severe preeclampsia to whom maternal plasma NO levels were determined by chemiluminescence before and after hydralazine administration. Blood pressure values were concomitantly assessed.

RESULTS

After 20 min of intravenous hydralazine infusion blood pressure values decrease significantly in term and preterm gestations. This was accompanied by an overall significant decrease in mean plasma NO values (38.7 ± 12.9 to 35.4 ± 13.9 μmol/L, p < 0.05). Despite this, NO values decreased in 67.5% of cases (a 17.6% from baseline) and increased in 32.5% (a 14.8% from baseline) (p < 0.05 for both). Blood pressure decrease (%) was lower (systolic and diastolic) among those displaying a NO decrement than in the increment group. Interestingly, gestational age was higher in the group displaying decreased NO; however, this did not reach statistical significance (37.5 ± 2.7 vs. 35.9 ± 2.8 weeks, p = 0.08).

CONCLUSION

The results of this study fail to demonstrate a similar NO secretion after hydralazine infusion in women with severe preeclampsia.

Lack of association between TNF-α gene polymorphisms at position -308 A, -850T and risk of simple febrile convulsion in pediatric patients

Background:

Febrile convulsions (FCs), occurring between 6 months and 6 years of age is the most common seizure disorder during childhood. The febrile response is thought to be mediated by the release of pyrogenic cytokines, such as tumor necrosis factor and interleukin-1 (IL-1). There is a significant relationship between genetic components for susceptibility of FCs and different report mutation. We investigated association between two polymorphisms in the tumor necrosis factor (TNF)-α promoter region (G-308A, C-850T) and FCs in the southwest area of Iran.

Materials and Methods:

In this matched case–control study, 100 patients with febrile convulsion as case group and 130 healthy children as control group were enrolled in the study. Peripheral blood samples were collected and DNA was extracted by standard phenol–chloroform method. The genotype and allele frequencies of TNF- α polymorphisms in case and control groups were determined by using PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism) method. Statistical analysis was done using Chi-square test.

Results:

The average age of case and control groups were 3.4 ± 1.4 and 3.4 ± 1.2 years, respectively. There was no significant difference between age and sex in both the groups (P > 0.05). A family history of febrile convulsion was detected in 44% of patients. Moreover, the simple febrile convulsion was detected in 85% of the case group.

Conclusion:

RFLP analysis of TNF- α promoter region polymorphisms, considering P = 0.146 and P = 0.084 for G-308A and C-850T, respectively, showed no correlation between TNF- α polymorphisms and predisposition to simple febrile, based on the kind of convulsion (atypical and simple febrile convulsion). We found a significant relation between genotype distribution of G-308A and atypical febrile convulsion in case group (P = 0.04). A significant correlation between genotype distribution of G-308A and atypical febrile convulsion in the case group was found, but there was no correlation between TNF- α polymorphisms at positions of -308A, and 850T and predisposition to simple febrile convulsion. Further studies are needed to understand clinical usefulness of this correlation.

Analysis of C-850T and G-308A Polymorphisms of theTumor Necrosis Factor-α Gene in Maya-Mestizo Women with Preeclampsia

OBJECTIVE

To determine whether polymorphisms in the TNF-alpha promoter gene are associated with preeclampsia.

METHODS

105 women with preeclampsia and 200 controls were genotyped for the G-308A and C-850T polymorphisms by RFLP. Differences in allele, genotype, and haplotype frequencies between groups were assessed.

RESULTS

The genotypic and allelic distribution of both polymorphisms was similar between groups. Moreover, the estimated overall pair of loci haplotype frequencies did not differ significantly.

CONCLUSION

We did not find any association between these polymorphisms and the risk for preeclampsia. However, we found that both the genotypic and allelic distribution in our population differed from those reported in other populations.

Human tumour necrosis factor: physiological and pathological roles in placenta and endometrium

The cytokine tumour necrosis factor alpha (TNF) is a well known member of the TNF superfamily consisting of at least 18 ligands and 29 different receptors involved in numerous cellular processes. TNF signals through two distinct receptors TNFR1 and TNFR2 thereby controlling expression of cytokines, immune receptors, proteases, growth factors and cell cycle genes which in turn regulate inflammation, survival, apoptosis, cell migration, proliferation and differentiation. Since expression of TNF was discovered in amnion and placenta many studies demonstrated the presence of the cytokine and its receptors in the diverse human reproductive tissues. Whereas TNF has been implicated in ovulation, corpus luteum formation and luteolysis, this review focuses on the functions of TNF in human placental, endometrial and decidual cell types of normal tissues and also discusses its role in endometrial and gestational diseases. Physiological levels of the cytokine could be important for balancing cell fusion and apoptotic shedding of villous trophoblasts and to limit trophoblast invasion into maternal decidua. Regulation of the TNF/TNFR system by steroid hormones also suggests a role in uterine function including menstrual cycle-dependent destruction and regeneration of endometrial tissue. Aberrant levels of TNF, however, are associated with diverse reproductive diseases such as amniotic infections, recurrent spontaneous abortions, preeclampsia, preterm labour or endometriosis. Hence, concentrations, receptor distribution and length of stimulation determine whether TNF has beneficial or adverse effects on female reproduction and pregnancy.

Association between tumor necrosis factor (TNF)-alpha G-308A gene polymorphism and preeclampsia complicated by severe fetal growth restriction

BACKGROUND

Preeclampsia and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome are multifactorial disorders with genetic and environmental components. Given that the tumor necrosis factor (TNF)-alpha G-308A single nucleotide polymorphism (SNP) affects TNF-alpha gene transcription and that preeclampsia and HELLP syndrome are characterized by a shift towards a Th1-type maternal immune response with increased TNF-alpha production, the aim of the current study was to investigate whether this SNP is associated with preeclampsia and HELLP syndrome in a Caucasian population from Hungary. Additionally, we aimed to examine whether TNF-alpha G-308A polymorphism can influence the risk for fetal growth restriction in preeclamptic patients, which issue none of the earlier studies dealt with.

METHODS

In a case-control study, we analyzed blood samples from 140 preeclamptic patients, 69 patients with HELLP syndrome and 144 normotensive, healthy pregnant women using the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. We performed also a meta-analysis with our results and those of 8 previously published studies.

RESULTS

There were no significant differences in the genotype and allele frequencies of the TNF-alpha G-308A polymorphism between preeclamptic patients and normotensive, healthy pregnant women. However, the mutant (TNF2 or A) allele occurred significantly more frequently in preeclamptic patients with IUGR than in those without IUGR (18.5% versus 7.1%, p=0.003). In addition, the frequency of the mutant allele carriers was significantly higher among preeclamptic patients with IUGR compared to those without IUGR (30.6% versus 12.8%, p=0.010). The mutant allele carriers were found to have an increased risk of severe IUGR-complicated preeclampsia, which was independent of maternal age, prepregnancy BMI and primiparity (odds ratio (OR): 2.89, 95% confidence interval (CI): 1.16-7.22, p=0.023; adjusted OR: 2.78, 95% CI: 1.04-7.45, p=0.042). Nevertheless, no significant differences were detected in the genotype and allele frequencies of the TNF-alpha G-308A polymorphism between patients with HELLP syndrome and control subjects. In the meta-analysis, no association was observed between this SNP and preeclampsia (summary OR: 0.956, 95% CI: 0.693-1.319).

CONCLUSIONS

Although the meta-analysis demonstrated a lack of an overall association between TNF-alpha G-308A polymorphism and preeclampsia, our results suggest a role of this SNP in the risk of severe IUGR-complicated preeclampsia. However, further studies are required with a larger sample size to confirm our findings.

Genetic association of preeclampsia to the inflammatory response gene SEPS1

OBJECTIVE

The objective of the study was to test for a genetic association between the G-105A promoter polymorphism of the inflammatory mediator Selenoprotein S (SEPS1) and preeclampsia.

STUDY DESIGN

A retrospective study in a large Norwegian case-control cohort compared maternal genotype and allele frequencies of the SEPS1 g.-105G>A polymorphism genotyped by SNPlex assay in preeclamptic (n = 1139) and control (n = 2269) women. Statistical significance was determined by chi2 and multivariate regression analyses.

RESULTS

Women with preeclampsia were 1.34 times more likely to have the GA or AA genotype (P = .0039; 95% confidence interval [CI] 1.09 to 1.64) and 1.22 times more likely to carry the A allele (P = .023; odds ratio, 1.22; 95% CI, 1.02 to 1.46).

CONCLUSION

The A allele of the SEPS1-105G>A polymorphism is a significant risk factor for preeclampsia in this population.

Tumor necrosis factor-alpha in gestation and puerperium of women with gestational hypertension and pre-eclampsia

PROBLEM

High plasma levels of tumor necrosis factor-alpha (TNF-alpha) in pregnant women have been associated with the pathogenesis of pre-eclampsia (PE). This study evaluated TNF-alpha plasma levels and monocyte production in gestational hypertension (GH) and PE during gestation and at puerperium.

METHOD OF STUDY

This study included 128 women, of whom 20 were non-pregnant (NP) normotensive (NT), and 108 were pregnant: 36 NT, 27 with GH, and 45 with PE. Peripheral blood plasma was used for TNF-alpha and uric acid determination. TNF-alpha was determined in plasma and lipopolysaccharide (LPS)-stimulated and non-stimulated monocyte supernatants by L929 bioassay.

RESULTS

Tumor necrosis factor-alpha and uric acid plasma levels were higher in PE than in GH pregnancies. In both hypertensive groups, these parameters positively correlated and were significantly more elevated than in NT and NP women. TNF-alpha plasma levels and monocyte production were higher in hypertensive than in NT women during gestation, and significantly decreased at puerperium. Although decreased, TNF-alpha release in LPS-stimulated PE monocytes, was still significantly higher than in the other pregnant groups.

CONCLUSION

In vivo monocyte activation in GH and PE pregnant women was characterized by in vitro TNF-alpha production. The fact that higher circulating concentrations of TNF-alpha and uric acid were observed in PE than in GH suggests an association with disease severity.

Plasma Cell Membrane Glycoprotein-1 K121Q Polymorphism in Preeclampsia

BACKGROUND

Preeclampsia is a common hereditary disease with unclear aetiology and various genetic and environmental components. We wanted to determine whether genetic variability in the gene encoding plasma cell membrane glycoprotein-1 (PC-1) contributes to individual susceptibility to the development of preeclampsia.

METHODS

The case-control study involved 133 women with preeclampsia and 115 healthy controls. They were genotyped for the K121Q polymorphism in the PC-1 gene. chi(2) analysis was used to assess genotype and allele frequency differences between preeclamptic and control women.

RESULTS

The frequency of the PC-1 gene 121K allele was found to be equal in the two groups, being 90.2% among women with preeclampsia and 90.4% among controls (p = 0.937; OR = 1.024; 95% CI = 0.564-1.861). Also the genotype distribution of the PC-1 K121Q polymorphism was similar (p = 0.516) in the preeclamptic and control groups.

CONCLUSIONS

The K121Q polymorphism of the PC-1 gene is unlikely to be a major genetic factor predisposing to preeclampsia in Finnish women.

Tumour necrosis factor-alpha gene haplotype is associated with pre-eclampsia

We determined whether polymorphisms in the promoter region of the tumour necrosis factor alpha (TNF-alpha) gene contributes to differences in susceptibility to develop pre-eclampsia. The study involved 133 pre-eclamptic and 115 healthy pregnant women who were genotyped for the G-308A polymorphism of the TNF-alpha gene. The frequency of the G-308A allele was more common in the pre-eclampsia group than among the controls (P=0.046), giving an odds ratio of 0.57 (95% CI: 0.32-0.99), but there were no differences in the genotype distribution. The data from the G-308A polymorphism was combined with the previously published genotype and allele data from the C-850T polymorphism of the TNF-alpha gene, and used to assess a haplotype estimation analysis. Estimated overall pair of loci haplotype frequencies differed significantly between the groups (P=0.023+/-0.004). In the single haplotype association analysis, the haplotype C-A versus others was over-represented in the pre-eclampsia group (P=0.041+/-0.003), whereas the haplotype T-G versus others was less common in the pre-eclampsia group (P=0.035+/-0.003), compared with the controls. In conclusion, the polymorphisms of the TNF-alpha gene showed a significant haplotype association with susceptibility to pre-eclampsia in the Finnish population.

Short- and Long-Term Changes in Plasma Inflammatory Markers Associated With Preeclampsia

Preeclampsia is characterized by hypertension, dyslipidemia, and increased systemic inflammatory response and has been associated with an increased maternal risk of cardiovascular disease later in life. Low-grade chronic inflammation is a risk factor for cardiovascular disease. This study examined changes in inflammatory markers prospectively during pregnancy, the current inflammatory status of women who had a pregnancy complicated by preeclampsia 20 years previously against matched controls, and the association between inflammatory genes and risk of preeclampsia in a case (n=106) control (n=212) study. In control pregnancies (n=34), mean interleukin-10 (IL-10) levels increased 38% ( P =0.012) and tumor necrosis factor-α (TNF-α) by 33% ( P =0.024) between the first and third trimesters. The mean preeclampsia group IL-10 and TNF-α rose by 43% ( P =0.013 and P =0.0065, respectively) from the first to the third trimester. In women with preeclampsia only, plasma IL-6 increased from the first to the third trimester (1.66 [2.04] to 2.94 [2.47] pg/mL; P =0.0004). Twenty years after the index pregnancy, women who had had preeclampsia demonstrated significantly higher IL-6 to IL-10 ratio (3.96 [6.07] versus 2.12 [1.89]; P =0.034) compared with a healthy index pregnancy 20 years previously, that persisted after adjustment for smoking and current body mass index. The IL-1β (C-511T), IL-6 (G-174C), TNF-α (G-308A), E-selectin (S128R), intercellular adhesion molecule-1 (K469E), and C-reactive protein (C1059G) polymorphisms were not associated with risk of developing preeclampsia. In conclusion, preeclampsia is associated with short- and long-term changes in inflammatory status.

Prediction of preeclampsia: can it be achieved?

In this review, the various biochemical tests that have been proposed for the prediction of preeclampsia are described and evaluated. Placenta hormone markers do not predict future disease. They denounce the early placental changes that are part of the evolving disease and only predict the imminent of preeclamptic syndrome. This explains why tests are better predictors when preeclampsia supervenes shortly, and why screening in the first trimester is unlikely to work as well as in the second trimester. The use of multiple markers in the screening should reflect different aspects of the disease process and could increase the specificity and sensitivity of the screening and work on different etiologic factors. The possible use of second-trimester biochemical screening to predict the risk of preeclampsia remains to be investigated in the high-risk population.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians

LEARNING OBJECTIVES

After completion of this article, the reader should be able to list the various theories on the etiology of preeclampsia, to relate the various risk factors for the development of preeclampsia, and to describe the various screening tests for preeclampsia.