Increased serum iron levels in pregnant women with preeclampsia: a meta-analysis of observational studies

Abstract

Our study aimed to investigate whether the serum iron levels in patients with preeclampsia were higher than in healthy pregnant women and to evaluate potential heterogeneities. We searched Pubmed, Embase, Web of Science and Medline databases for studies before September 2016. The standardised mean difference (SMD) and 95% confidence interval (CI) were used to combine results across the studies, in addition to the random-effect model. A total of 10 studies involving 363 patients with preeclampsia and 370 healthy controls were eligible through the inclusion criteria. In comparison with healthy pregnant women, the serum iron levels are higher in the patients with preeclampsia [summary SMD = 0.28, 95% CI = 0.11-0.44], and this association was also significant in the case-control studies. The serum iron levels were higher in the pregnant women with preeclampsia than in the healthy controls in both the Asian and European populations. Our study provides significant evidence of higher serum iron levels in the patients with preeclampsia than in healthy pregnant women. Impact Statement What is already known on this subject? Serum iron levels have inconsistent associations with a risk of preeclampsia in pregnant women. What the results of this study add? Compared with healthy pregnant women, serum iron levels are higher in patients with preeclampsia. What the implications are of these findings for clinical practice and/or further research? Further studies across large numbers of cases and increased patient populations are necessary to confirm our findings.

miR-30-5p-mediated ferroptosis of trophoblasts is implicated in the pathogenesis of preeclampsia

“…Liable Fe(II) is vital for ferroptosis, as it contributes greatly to the generation of lipid peroxides. Numerous studies has confirmed that the total serum iron content is higher in patients with PE than in healthy pregnancy, with Orlov et al even reporting that the serum iron level has a direct correlation with the blood pressure level [[16], [17], [18]]. However, no study had investigated the level of Fe(II) in placental tissues.…”

Can Serum Iron Concentrations in Early Healthy Pregnancy Be Risk Marker of Pregnancy-Induced Hypertension?

“…Retrospective studies are more numerous [16,17,23,24,25,26]. Fenzl et al [25] showed significantly higher serum iron concentrations in 30 women with preeclampsia, compared to 37 healthy pregnant women.…”

“…In contrast, Sarwar et al [17] found significantly lower serum iron concentrations in 50 women with preeclampsia, compared to 58 women of the control group. The meta-analysis of 10 studies conducted by Liu et al [16] provided significant evidence for higher serum/plasma iron concentrations in women with preeclampsia compared to healthy women in both the Asian and European population.…”

“…In the world literature, studies which assess the association of iron concentrations with pregnancy-induced hypertension are available, but these are mainly retrospective studies regarding women with already developed disease. As shown by meta-analyses, in most retrospective studies, statistically significantly higher serum iron concentrations were found in women with preeclampsia compared to normotensive women [16], but there are also contrary results [17]. However, iron concentrations, in women who have already developed the disease, may be a result of existing disorders.…”

Moderate‐intensity aerobic training reduces cardiac damage attributable to experimental iron overload in rats

“…Transferrin saturation also exceeded 20−50%, the limit commonly used to diagnose iron overload (Elsayed et al, 2016;Sebastiani et al, 2012). In addition to being a consequence of disorders related to iron metabolism or recurrent blood transfusions, an elevated serum iron level is also considered a risk factor for increased mortality in patients with sepsis (Lan et al, 2018), pre-eclampsia in pregnant women (Liu et al, 2019) and several types of cancers, such as liver, lung and breast (Chen et al, 2018;Wen et al, 2014). In this regard, the present experimental animal model of parenteral administration is commonly used to simulate a chronic state of iron overload in humans, regardless of the aetiology.…”