Intravenous compared with oral iron for the treatment of iron-deficiency anemia in pregnancy: a systematic review and meta-analysis

Effectiveness of Oral Iron Therapy in Anemic Inpatient Pregnant Women: A Single Center Retrospective Cohort Study

Background and aim Oral iron therapy is effective in treating iron deficiency anemia in outpatient pregnant women but has not been studied in inpatient pregnant women. We aimed to evaluate the effect of oral iron therapy versus no therapy during hospitalization on maternal and neonatal outcomes in women with anemia who are hospitalized for pregnancy-related morbidities (i.e., preterm premature rupture of membranes, preterm labor, pre-eclampsia, abnormal placentation, or fetal monitoring). Methods A retrospective, single-center study was conducted in hospitalized pregnant women (2018 to 2020) with inpatient stays of more than three days. The primary outcome was a change in hemoglobin level from admission to delivery in women treated with oral iron compared with those left untreated. Secondary outcomes included the total amount of iron administered before delivery, the time interval from admission to delivery, and neonatal effects. Results Two hundred sixty-three women were admitted, 79 women had anemia, and 29 (36.7%) received at least one dose of oral iron. Baseline patient characteristics were similar between groups. The median (interquartile range) dose of iron in the oral iron group was 1185.0 (477.0, 1874.0) mg. Neither absolute hemoglobin before delivery (control group: 10.0±1.2 g/dL; iron group: 10.1±1.1 g/dL; p=0.774) nor change in hemoglobin from admission to delivery (control group: -0.1±1.1 g/dL vs. iron group: 0.4±1.1 g/dL; p=0.232) differed between groups. Women in the control group had shorter length of stay (LOS) median (IQR) than women in the iron group (control group: 7.1 (5.0, 13.7) days; iron group: 11.4 (7.4, 25.9) days; p=0.03). There were no differences in maternal mode of delivery, though each group had high rates of cesarean delivery (control group: 53.7%; iron group: 72.4%; p=0.181). There were no differences in estimated blood loss at delivery (control group: 559±401; iron group: 662.1±337.4;p=0.264) in either group. Neonatal birthweight (control group: 1.9±0.7 kg; iron group: 1.9±0.7 kg; p=0.901), birth hemoglobin (control group: 16.3±2.2 g/dL; iron group: 16±2.2 g/dL; p=0.569), neonatal intensive care unit (NICU) admission (control group: 93.3%; iron group: 84.8%;p=0.272 ), or neonatal death (control group: 8.9%; iron group: 3%; p=0.394) were not different between groups. Conclusions Oral iron administered to anemic inpatient pregnant women was not associated with higher hemoglobin concentrations before delivery. Lack of standardized iron regimens and short hospital stays may contribute to the inefficacy of oral iron for this inpatient pregnant population. The small sample size and retrospective nature of this study are limiting factors in drawing conclusive evidence from this study.

Clinical outcome post treatment of anemia in pregnancy with intravenous versus oral iron therapy: a systematic review and meta-analysis

Oral iron therapy is often the most common way of treating anaemia; however intravenous iron is considered effective due to rapid iron replenishment. We have dearth of evidence on clinical outcomes post treatment of anaemia. We have searched studies published in English in PubMed, Cochrane, Scopus, ProQuest, and Google Scholar. Our study analysed the clinical outcomes amongst neonates and mother and the adverse events post treatment and assessed the mean change in maternal haemoglobin concentration in both the groups. Forest plots for the clinical outcomes are presented. From a total of 370 studies, 34 Randomized and quasi experimental studies comparing clinical outcomes post-treatment of anaemia in pregnancy were included for quantitative evidence synthesis. Pooled results of maternal clinical outcomes using random effect model [OR: 0.79 (95% CI 0.66; 0.95); 10 outcomes; 17 studies] showed statistically significant difference among both the groups [Moderate quality evidence]; however no significant difference [OR: 0.99 (95% CI 0.86; 1.14); 7 outcomes; 8 studies] have been observed for neonatal complications [Low quality evidence]. The study found that pregnant women receiving IV iron were significantly less likely to experience adverse events as compared with those receiving oral iron [OR 0.39;  (95% CI 0.26-0.60)]; 34 studies; 13,909 women; [Low quality evidence]. Findings from meta-regression analysis showed that IV iron is more likely to reduce maternal complications by 21% compared to oral iron. Increase in odds of adverse maternal outcomes was observed due to increase in gestational age and publication year but no effect for the type of drug used. IV iron increases Hb more and at a higher pace than oral iron. Intravenous iron is more likely to avert adverse maternal outcomes and adverse reactions. However, there is no conclusive evidence on its effectiveness on individual maternal outcome or neonatal outcome/s. Protocol registered with PROSPERO CRD42022368346).

Vulnerabilities and reparative strategies during pregnancy, childbirth, and the postpartum period: moving from rhetoric to action

Maternal outcomes throughout pregnancy, childbirth, and the postnatal period are influenced by interlinked and interdependent vulnerabilities. A comprehensive understanding of how various threats and barriers affect maternal and perinatal health is critical to plan, evaluate and improve maternal health programmes. This paper builds on the introductory paper of the Series on the determinants of maternal health by assessing vulnerabilities during pregnancy, childbirth, and the postnatal period. We synthesise and present the concept of vulnerability in pregnancy and childbirth, and map vulnerability attributes and their dynamic influence on maternal outcomes in early and late pregnancy and during childbirth and the postnatal period, with a particular focus on low-income and middle-income countries (LMICs). We summarise existing literature and present the evidence on the effects of various reparative strategies to improve pregnancy and childbirth outcomes. Lastly, we discuss the implications of the identified vulnerability attributes and reparative strategies for the efforts of policymakers, healthcare professionals, and researchers working towards improving outcomes for women and birthing people in LMICs.

The effect of digital health interventions on postpartum depression or anxiety: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to examine the effect of digital health interventions compared with treatment as usual on preventing and treating postpartum depression and postpartum anxiety.

DATA SOURCES

Searches were conducted in Ovid MEDLINE, Embase, Scopus, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov.

STUDY ELIGIBILITY REQUIREMENTS

The systematic review included full-text randomized controlled trials comparing digital health interventions with treatment as usual for preventing or treating postpartum depression and postpartum anxiety.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors independently screened all abstracts for eligibility and independently reviewed all potentially eligible full-text articles for inclusion. A third author screened abstracts and full-text articles as needed to determine eligibility in cases of discrepancy. The primary outcome was the score on the first ascertainment of postpartum depression or postpartum anxiety symptoms after the intervention. Secondary outcomes included screening positive for postpartum depression or postpartum anxiety --as defined in the primary study --and loss to follow-up, defined as the proportion of participants who completed the final study assessment compared with the number of initially randomized participants. For continuous outcomes, the Hedges method was used to obtain standardized mean differences when the studies used different psychometric scales, and weighted mean differences were calculated when studies used the same psychometric scales. For categorical outcomes, pooled relative risks were estimated.

RESULTS

Of 921 studies originally identified, 31 randomized controlled trials-corresponding to 5532 participants randomized to digital health intervention and 5492 participants randomized to treatment as usual-were included. Compared with treatment as usual, digital health interventions significantly reduced mean scores ascertaining postpartum depression symptoms (29 studies: standardized mean difference, -0.64 [95% confidence interval, -0.88 to -0.40]; I2=94.4%) and postpartum anxiety symptoms (17 studies: standardized mean difference, -0.49 [95% confidence interval, -0.72 to -0.25]; I2=84.6%). In the few studies that assessed screen-positive rates for postpartum depression (n=4) or postpartum anxiety (n=1), there were no significant differences between those randomized to digital health intervention and treatment as usual. Overall, those randomized to digital health intervention had 38% increased risk of not completing the final study assessment compared with those randomized to treatment as usual (pooled relative risk, 1.38 [95% confidence interval, 1.18-1.62]), but those randomized to app-based digital health intervention had similar loss-to-follow-up rates as those randomized to treatment as usual (relative risk, 1.04 [95% confidence interval, 0.91-1.19]).

CONCLUSION

Digital health interventions modestly, but significantly, reduced scores assessing postpartum depression and postpartum anxiety symptoms. More research is needed to identify digital health interventions that effectively prevent or treat postpartum depression and postpartum anxiety but encourage ongoing engagement throughout the study period.

Identifying and treating iron deficiency anemia in pregnancy

Anemia is common during pregnancy, and while most anemia is physiologic, the most common pathologic cause is iron deficiency. The American College of Obstetricians and Gynecologists (ACOG) recommends confirmation of iron deficiency anemia with iron studies when anemia is diagnosed during pregnancy but acknowledges that presumptive treatment for suspected iron deficiency anemia is common in practice. Currently ACOG does not recommend treating iron deficiency without anemia during pregnancy. Though the benefits of treating iron deficiency anemia during pregnancy are clear, the optimal route of iron repletion remains uncertain. Results of ongoing large, randomized trials will help define the optimal route of iron treatment for pregnant patients diagnosed with iron deficiency anemia.

Biology of Anemia: A Public Health Perspective

Our goal is to present recent progress in understanding the biological mechanisms underlying anemia from a public health perspective. We describe important advances in understanding common causes of anemia and their interactions, including iron deficiency (ID), lack of other micronutrients, infection, inflammation, and genetic conditions. ID develops if the iron circulating in the blood cannot provide the amounts required for red blood cell production and tissue needs. ID anemia develops as iron-limited red blood cell production fails to maintain the hemoglobin concentration above the threshold used to define anemia. Globally, absolute ID (absent or reduced body iron stores that do not meet the need for iron of an individual but may respond to iron supplementation) contributes to only a limited proportion of anemia. Functional ID (adequate or increased iron stores that cannot meet the need for iron because of the effects of infection or inflammation and does not respond to iron supplementation) is frequently responsible for anemia in low- and middle-income countries. Absolute and functional ID may coexist. We highlight continued improvement in understanding the roles of infections and inflammation in causing a large proportion of anemia. Deficiencies of nutrients other than iron are less common but important in some settings. The importance of genetic conditions as causes of anemia depends upon the specific inherited red blood cell abnormalities and their prevalence in the settings examined. From a public health perspective, each setting has a distinctive composition of components underlying the common causes of anemia. We emphasize the coincidence between regions with a high prevalence of anemia attributed to ID (both absolute and functional), those with endemic infections, and those with widespread genetic conditions affecting red blood cells, especially in sub-Saharan Africa and regions in Asia and Oceania.

Intravenous iron for treatment of iron deficiency anemia during pregnancy and associated maternal outcomes

BACKGROUND

More than 40% of pregnant patients worldwide are anemic, with at least half resulting from iron deficiency anemia (IDA). Anemia in pregnancy is linked with adverse maternal and neonatal outcomes. Treatment for IDA is iron supplementation; however, the optimal route of administration remains unclear. We sought to investigate whether patients with IDA who received intravenous iron (IVI) had decreased odds of maternal morbidity compared to patients who did not.

METHODS

This is a retrospective cohort study of pregnant patients with presumed IDA with term deliveries at a tertiary hospital from 2013-2021. Data were extracted from the hospital's electronic medical record using standardized definitions and billing codes. Patients who received antepartum IVI were compared to patients who did not. The primary outcome was a maternal morbidity composite inclusive of receipt of blood transfusion, hysterectomy, admission to the intensive care unit or death. Bivariate analyses and multivariable logistic regression modelling were performed adjusting for potential confounders.

RESULTS

Of 45,345 pregnancies, 5054 (11.1%) met eligibility criteria. Of these, 944 (18.7%) patients received IVI while 4110 (81.3%) did not. Patients who received IVI had higher risk baseline characteristics. They experienced a greater increase in hematocrit from pregnancy nadir to delivery admission (4.5% vs. 3.3%, p < .01). Despite this, patients who received IVI had higher odds of the maternal morbidity composite (OR 1.47, 95%CI 1.11-1.95). This finding persisted after adjusting for potential confounders, although the strength of the association became attenuated (aOR 1.37, 95%CI 1.02-1.85). Odds of the morbidity composite were not elevated among patients who received a full IVI treatment course (OR 1.2, 95% CI 0.83-1.90).

DISCUSSION

Odds of the maternal morbidity composite were increased among patients who received IVI despite greater increases in hematocrit. The effect was attenuated after adjusting for potential confounders and was not significant among patients who completed a full treatment course.

Intravenous ferric derisomaltose versus oral iron for persistent iron deficient pregnant women: a randomised controlled trial

PURPOSE

To compare the efficacy of intravenous (IV) iron (ferric derisomaltose) with oral iron (ferrous fumarate) in women 14-21 weeks pregnant with persistent iron deficiency (ferritin < 30 µg/L).

METHODS

In a single-centre, open-label, randomised controlled trial at a Danish hospital, women with persistent iron deficiency after routine oral iron treatment were allocated to receive 1000 mg IV iron (single-dose) or 100 mg elemental oral iron daily. Outcomes were assessed during an 18-week follow-up period. The primary endpoint was the proportion of non-anaemic (haemoglobin [Hb] ≥ 11 g/dL) women throughout follow-up. Other outcomes included changes in haematological parameters, patient-reported fatigue, and quality of life (QoL). Safety was assessed by recording adverse events.

RESULTS

From July 2017 to February 2020, 100 women were randomised to IV iron and 101 to oral iron. Throughout follow-up, 91% of women were non-anaemic in the IV iron group compared with 73% in the oral iron group (18% difference [95% confidence interval 0.10-0.25]; p < 0.001). The mean Hb increase was significantly greater with IV iron versus oral iron at Weeks 6 (0.4 versus - 0.2 g/dL; p < 0.001), 12 (0.5 versus 0.1 g/dL; p < 0.001), and 18 (0.8 versus 0.5 g/dL; p = 0.01). Improvements in fatigue and QoL were greater with IV iron versus oral iron at Weeks 3 and 6. The incidence of treatment-related adverse events was comparable between treatment groups.

CONCLUSION

IV iron was superior in preventing anaemia compared with oral iron in pregnant women with persistent iron deficiency; biochemical superiority was accompanied by improved fatigue and QoL.

CLINICAL TRIAL REGISTRATION

European Clinical Trials Database: EudraCT no.: 2017-000776-29 (3 May 2017); ClinicalTrials.gov: NCT03188445 (13 June 2017). The trial protocol has been published: https://dx.doi.org/10.1186%2Fs13063-020-04637-z .

Quantifying differences in iron deficiency-attributable anemia during pregnancy and postpartum

Pregnant women in resource-limited settings are highly susceptible to anemia and iron deficiency, but the etiology of postpartum anemia remains poorly defined. To inform the optimal timing for anemia interventions, changes in iron deficiency-attributable anemia through pregnancy and postpartum need to be understood. In 699 pregnant Papua New Guinean women attending their first antenatal care appointment and following up at birth and 6 and 12 months postpartum, we undertake logistic mixed-effects modeling to determine the effect of iron deficiency on anemia and population attributable fractions, calculated from odds ratios, to quantify the contribution of iron deficiency to anemia. Anemia is highly prevalent during pregnancy and 12 months postpartum, with iron deficiency increasing the odds of anemia during pregnancy and, to a lesser extent, postpartum. Iron deficiency accounts for ≥72% of anemia during pregnancy and 20%-37% postpartum. Early iron supplementation during and between pregnancies could break the cycle of chronic anemia in women of reproductive age.

A systematic literature review and meta-analysis of the incidence of serious or severe hypersensitivity reactions after administration of ferric derisomaltose or ferric carboxymaltose

BACKGROUND

Intravenous iron is the preferred treatment for patients with iron deficiency anemia in a variety of clinical situations. Although uncommon, administration of modern IV iron formulations can result in hypersensitivity reactions (HSRs) and, rarely, anaphylactic or anaphylactoid reactions.

AIM

The objective of the present study was to systematically review the literature to identify and analyze data on the incidence of HSRs after administration of ferric derisomaltose (FDI) or ferric carboxymaltose (FCM).

METHOD

A prospectively-registered systematic literature review was conducted to identify prospective randomized controlled trials comparing FDI and FCM with other intravenous iron formulations or oral iron. Searches were conducted in PubMed (including MEDLINE), EMBASE, and the Cochrane Library in November 2020. The relative incidence of serious or severe HSRs occurring on the day or day after dosing of intravenous iron, recorded under the standardized Medical Dictionary for Regulatory Activities query for anaphylactic reaction.

RESULTS

Data were obtained from seven randomized controlled trials of FCM (N = 2683) and ten of FDI (N = 3474) enrolling 10,467 patients in total. The number of patients experiencing any serious or severe HSR event was 29/2683 (1.08%) with FCM versus 5/3474 with FDI (0.14%). Bayesian inference of proportions showed the event rates to be significantly lower with FDI relative to FCM.

CONCLUSION

HSR events were uncommon with both intravenous iron formulations; however, the present study showed a significantly lower incidence of HSRs with FDI relative to FCM. Further large-scale, head-to-head trials of the iron formulations would be required to confirm this finding.

The interplay between maternal-infant anemia and iron deficiency

Iron deficiency anemia in pregnancy is a major public health problem known to cause maternal morbidity and adverse birth outcomes, and it may also have lasting consequences on infant development. However, the impact of the maternal hematological environment on fetal and infant hemoglobin and iron stores in the first year of life remains unclear. This review of the epidemiological evidence found that severe maternal iron deficiency anemia in pregnancy is associated with lower ferritin, and to a lesser degree hemoglobin levels, in infants at birth. Emerging data also suggests that severe anemia in pregnancy increases the risk of iron deficiency and anemia in infants 6-12 months of age, although longitudinal studies are limited. Effective anemia prevention in pregnancy, such as iron supplementation, could reduce the risk of infant anemia and iron deficiency during the first year of life; however, more evidence is needed to determine the functional impact of iron supplementation in pregnancy on infant hematological indices.

The incidence, complications, and treatment of iron deficiency in pregnancy

Iron deficiency and/or iron deficiency anemia (IDA) complicate nearly 50% of pregnancies globally, negatively impacting both maternal and fetal outcomes. Iron deficiency can cause a range of symptoms that range from aggravating to debilitating including fatigue, poor quality of life, pagophagia, and restless leg syndrome. Iron deficiency and IDA are also associated with maternal complications including preterm labor, increased rates of cesarean delivery, postpartum hemorrhage, and maternal death. Fetal complications include increased rates of low birth weight and small for gestational age newborns. Prenatal maternal anemia has also been associated with autism spectrum disorders in the neonate, although causation is not established. Deficiency in the newborn is associated with compromised memory, processing, and bonding, with some of these deficits persisting into adulthood. Despite the prevalence and consequences associated with iron deficiency in pregnancy, data show that it is routinely undertreated. Due to the physiologic changes of pregnancy, all pregnant individuals should receive oral iron supplementation. However, the bioavailability of oral iron is poor and it is often ineffective at preventing and treating iron deficiency. Likewise, it frequently causes gastrointestinal symptoms that can worsen the quality of life in pregnancy. Intravenous iron formulations administered in a single or multiple dose series are now available. There is increasing data suggesting that newer intravenous formulations are safe and effective in the second and third trimesters and should be strongly considered in pregnant individuals without optimal response to oral iron repletion.

Protocol for a multicenter, double-blinded placebo-controlled randomized controlled trial comparing intravenous ferric derisomaltose to oral ferrous sulfate for the treatment of iron deficiency anemia in pregnancy: The IVIDA2 trial

BACKGROUND

Iron deficiency anemia (IDA) is common during pregnancy and associated with adverse maternal and neonatal outcomes. Treatment with iron supplementation is recommended during pregnancy, but the optimal delivery route is unclear. Oral iron risks has high risk of gastrointestinal side effects and low absorption. Intravenous iron is infused directly but is expensive. The American College of Obstetricians and Gynecologists currently recommends oral iron to treat IDA in pregnancy with intravenous iron reserved as second-line therapy, if needed. This approach is associated with persistent anemia, increasing the risk of peripartum blood transfusion. We aim to provide data on optimal route of iron repletion for IDA in pregnancy.

METHODS

In IVIDA2, a double-blind, placebo controlled, multicenter randomized trial in the United States, 746 pregnant people with moderate-to-severe IDA (hemoglobin <10 g/dL and ferritin <30 ng/mL) at 24-28 weeks' gestation will be randomized 1:1 to either a single 1000 mg dose of intravenous ferric derisomaltose and oral placebo (1-3 times daily) or a single placebo infusion with 1-3 times daily 325 mg ferrous sulfate (65 mg elemental iron) tablet. The primary outcome is peripartum blood transfusion (blood transfusion from delivery to 7 days postpartum). Secondary outcomes include adverse medication reactions, maternal and neonatal hematologic indices, and offspring neurodevelopment.

ETHICS AND DISSEMINATION

A central ethical review board-Advarra-granted ethical approval (Pro00060930). Participating centers-Women & Infants Hospital of Rhode Island, University of Michigan Medical Center, Washington University School of Ethics and dissemination: A central ethical review board-Advarra-granted ethical approval (Pro00060930). Participating centers-Women & Infants Hospital of Rhode Island, University of Michigan Medical Center, Washington University School of.

An implementation research programme to support an intravenous iron intervention for pregnant women with moderate and severe anaemia in Malawi: study protocol

Background

Antenatal iron supplementation is critical to maternal and child health; however, access and adherence to oral iron are inconsistent in many low- and middle-income countries (LMICs). Modern intravenous (IV) iron products have become available in high-income clinical settings and provide an opportunity to deliver high doses of iron in a single-short infusion during pregnancy. However, there is limited knowledge of the drivers and barriers for such an intervention to be effectively delivered and upscaled in LMICs. In this study protocol, we describe the implementation research programme to support an IV iron intervention in Malawi for pregnant women with moderate and severe anaemia.

Methods

The implementation research programme has three phases, each guided by implementation science conceptual frameworks. In Phase 1, we will conduct formative research (context assessment of the health system with key informant interviews) to determine how IV iron can be effectively introduced into routine antenatal care. We will use the findings to co-develop potential strategies with end-users and healthcare providers to improve intervention implementation. In Phase 2, we will disseminate the implementation strategies to support the uptake and delivery of the intervention in the study settings. In Phase 3, the intervention will be implemented, and we will conduct formative evaluation (interviews with end-users, healthcare providers, and analysis of health services data) to investigate the feasibility and acceptability of the intervention and strategies. We will also identify processes and contextual factors that facilitate or impede the delivery and uptake of IV iron.

Discussion

In LMICs, modern IV iron products present a novel opportunity to rapidly cure moderate and severe anaemia in pregnancy, thereby improving maternal and child health outcomes. This implementation research programme will provide guidance and recommendations on how best an IV iron intervention for pregnant women with anaemia can be implemented in an LMIC setting like Malawi. We will develop locally relevant and culturally appropriate implementation strategies by engaging with key stakeholders (pregnant women, healthcare providers, and policymakers) and identifying factors likely to facilitate successful implementation. The findings of this research can guide the implementation of an IV iron intervention in Malawi and other LMICs.

Intravenous versus oral iron for iron deficiency anaemia in pregnant Nigerian women (IVON): study protocol for a randomised hybrid effectiveness-implementation trial

Background

Anaemia in pregnancy is highly prevalent in African countries. High-dose oral iron is the current recommended treatment for pregnancy-related iron deficiency anaemia (IDA) in Nigeria and other African countries. This oral regimen is often poorly tolerated and has several side effects. Parenteral iron preparations are now available for the treatment of IDA in pregnancy but not widely used in Africa.

The IVON trial is investigating the comparative effectiveness and safety of intravenous ferric carboxymaltose versus oral ferrous sulphate standard-of-care for pregnancy-related IDA in Nigeria. We will also measure the implementation outcomes of acceptability, feasibility, fidelity, and cost-effectiveness for intravenous ferric carboxymaltose.

Methods

This is an open-label randomised controlled trial with a hybrid type 1 effectiveness-implementation design, conducted at 10 health facilities in Kano (Northern) and Lagos (Southern) states in Nigeria. A total of 1056 pregnant women at 20–32 weeks’ gestational age with moderate or severe anaemia (Hb < 10g/dl) will be randomised 1:1 into two groups. The interventional treatment is one 1000-mg dose of intravenous ferric carboxymaltose at enrolment; the control treatment is thrice daily oral ferrous sulphate (195 mg elemental iron daily), from enrolment till 6 weeks postpartum.

Primary outcome measures are (1) the prevalence of maternal anaemia at 36 weeks and (2) infant preterm birth (<37 weeks’ gestation) and will be analysed by intention-to-treat. Maternal full blood count and iron panel will be assayed at 4 weeks post-enrolment, 36 weeks’ gestation, delivery, and 6 weeks postpartum. Implementation outcomes of acceptability, feasibility, fidelity, and cost will be assessed with structured questionnaires, key informant interviews, and focus group discussions.

Discussion

The IVON trial could provide both effectiveness and implementation evidence to guide policy for integration and uptake of intravenous iron for treating anaemia in pregnancy in Nigeria and similar resource-limited, high-burden settings. If found effective, further studies exploring different intravenous iron doses are planned.

Trial registration

ISRCTN registry ISRCTN63484804. Registered on 10 December 2020

Clinicaltrials.govNCT04976179. Registered on 26 July 2021

The current protocol version is version 2.1 (080/080/2021).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06690-2.

Intravenous versus Oral Iron for Iron-Deficiency Anemia in Pregnancy (IVIDA): A Randomized Controlled Trial

OBJECTIVE

Iron-deficiency anemia (IDA) can have serious consequences for mothers and babies. Iron supplementation is recommended, but the administration route is controversial. We sought to conduct a randomized controlled trial (RCT) testing the effectiveness and safety of intravenous (IV) iron compared with oral iron on perinatal outcomes in pregnant women with IDA.

STUDY DESIGN

This open-label RCT randomized patients with IDA (hemoglobin [hgb] <10 g/dL and ferritin <30 ng/mL) at 24 to 34 weeks' to oral iron or single 1,000-mg dose of IV low-molecular weight iron dextran over one hour. The primary outcome was maternal anemia at delivery (hgb < 11 g/dL). Secondary outcomes were mild/moderate or severe adverse reactions, maternal hgb and ferritin at delivery, blood transfusion, gestational age at delivery, birth weight, neonatal hgb and ferritin, and composite neonatal morbidity. Analysis was as per protocol.

RESULTS

The trial was stopped early for logistical reasons, and the data analyzed as preliminary data to inform a larger, potentially externally funded, definitive trial. Of 55 patients approached, 38 consented. Of these, 15 were withdrawn: 5 received IV iron from their primary obstetrician after being randomized to oral iron and 10 declined to receive IV iron. Of the remaining 23 patients, who were included in the analytic population, 13 received oral iron and 10 received IV iron. The rate of maternal anemia at delivery (hgb < 11 g/dL) was high overall but significantly reduced with IV iron (40 vs. 85%, p = 0.039). Rates of maternal hgb < 10 g/dL were significantly lower in the IV iron group (10 vs. 54%, p = 0.029). There were no severe adverse reactions and similar rates of mild/moderate reactions between groups.

CONCLUSION

IV iron reduces rates of anemia at the time of admission for delivery, supporting a larger RCT comparing IV versus oral iron for the treatment of IDA of pregnancy powered for definitive clinical outcomes. However, issues uncovered in this RCT suggest that patient, clinician, and systems-level barriers associated with different IDA treatment modalities must be considered prior to conducting a larger RCT. This study is registered with clinicaltrials.gov with identifier no.: NCT03438227.

KEY POINTS

· IV iron decreases rates of anemia on admission for delivery compared with oral iron.. · In an unblinded randomized trial, a significant proportion of patients preferred alternate therapy.. · Future RCTs should incorporate double-blinded technique to reduce risk of patient crossover.. · Results from feasibility trial support a larger RCT comparing IV to oral iron for IDA in pregnancy..

Screening, Treatment, and Monitoring of Iron Deficiency Anemia in Pregnancy and Postpartum

Iron deficiency anemia is the most prevalent form of anemia worldwide. In the United States, clinicians routinely screen for iron deficiency anemia upon initiation of prenatal care, at the start of the third trimester, and prior to birth. Treatment of iron deficiency anemia generally begins with oral supplementation of elemental iron, which is associated with adverse gastrointestinal effects. These adverse effects can decrease adherence, leading to subtherapeutic treatment. Newer evidence highlights the benefits of early screening for iron deficiency before the onset of anemia, as well as the use of intravenous iron to expedite the treatment of iron deficiency anemia. More research is needed on the potential consequences of over-supplementation and iron deficiency without anemia to guide treatment. This article reviews the evidence for best practices for screening, treatment, and continued monitoring of iron deficiency anemia during pregnancy and postpartum. Maternal, fetal, and neonatal implications are reviewed, as well as the risks and benefits of treatment options. Finally, an evidence-based algorithm is proposed to guide clinicians on continued monitoring after treatment.

Diagnosis and Therapy of Iron Deficiency Anemia During Pregnancy: Recommendation of the Austrian Society for Gynecology and Obstetrics (OEGGG)

This overview analyzes the data on the controversial therapy of iron substitution during pregnancy, the diagnosis of iron deficiency anemia and the indication-related therapy, and is the first recommendation issued by the OEGGG on the appropriate therapy. The effects of anemia during pregnancy on postnatal outcomes have been intensively investigated with heterogeneous results. A final scientific conclusion with regards to the "optimal" maternal hemoglobin level is limited by the heterogeneous results of various studies, many of which were conducted in emerging nations (with different dietary habits and structural differences in the respective healthcare systems). The current literature even suggests that there may be a connection between both decreased and increased maternal serum hemoglobin concentrations and unfavorable short-term and long-term neonatal outcomes. In Austria, 67 percent of pregnant women take pharmacological supplements or use a variety of dietary supplements. Clinically, the prevalence of maternal anemia is often overestimated, leading to overtreatment of pregnant women (iron substitution without a medical indication). To obtain a differential diagnosis, a workup of the indications for treatment should be carried out prior to initiating any form of iron substitution during pregnancy. If treatment is medically indicated, oral iron substitution is usually sufficient. Because of the restricted approval and potential side effects, medical indications for intravenous iron substitution should be limited. Intravenous iron substitution without a prior detailed diagnostic workup is an off-label use and should only be used in very limited cases, and women should be advised accordingly.

The Influence of Nutritional Supplementation for Iron Deficiency Anemia on Pregnancies Associated with SARS-CoV-2 Infection

Anemia is a very common occurrence during pregnancy, with important variations during each trimester. Anemia was also considered as a risk factor for severity and negative outcomes in patients with SARS-CoV-2 infection. As the COVID-19 pandemic poses a significant threat for pregnant women in terms of infection risk and access to care, we developed a study to determine the impact of nutritional supplementation for iron deficiency anemia in correlation with the status of SARS-CoV-2 infection. In a case-control design, we identified 446 pregnancies that matched our inclusion criteria from the hospital database. The cases and controls were stratified by SARS-CoV-2 infection history to observe the association between exposure and outcomes in both the mother and the newborn. A total of 95 pregnant women were diagnosed with COVID-19, having a significantly higher proportion of iron deficiency anemia. Low birth weight, prematurity, and lower APGAR scores were statistically more often occurring in the COVID-19 group. Birth weight showed a wide variation by nutritional supplementation during pregnancy. A daily combination of iron and folate was the optimal choice to normalize the weight at birth. The complete blood count and laboratory studies for iron deficiency showed significantly decreased levels in association with SARS-CoV-2 exposure. Puerperal infection, emergency c-section, and small for gestational age were strongly associated with anemia in patients with COVID-19. It is imperative to screen for iron and folate deficiency in pregnancies at risk for complications, and it is recommended to supplement the nutritional intake of these two to promote the normal development and growth of the newborn and avoid multiple complications during pregnancy in the COVID-19 pandemic setting.

Questions and answers on iron deficiency treatment selection and the use of intravenous iron in routine clinical practice

Iron deficiency is a common cause of morbidity and can arise as a consequence or complication from many diseases. The use of intravenous iron has increased significantly in the last decade, but concerns remain about indications and administration. Modern intravenous iron preparations can facilitate rapid iron repletion in one or two doses, both for absolute iron deficiency and, in the presence of inflammation, functional iron deficiency, where oral iron therapy is ineffective or has not worked. A multidisciplinary team of experts experienced in iron deficiency undertook a consensus review to support healthcare professionals with practical advice on managing iron deficiency in gastrointestinal, renal and cardiac disease, as well as; pregnancy, heavy menstrual bleeding, and surgery. We explain how intravenous iron may work where oral iron has not. We provide context on how and when intravenous iron should be administered, and informed opinion on potential benefits balanced with potential side-effects. We propose how intravenous iron side-effects can be anticipated in terms of what they may be and when they may occur. The aim of this consensus is to provide a practical basis for educating and preparing staff and patients on when and how iron infusions can be administered safely and efficiently. Key messages Iron deficiency treatment selection is driven by several factors, including the presence of inflammation, the time available for iron replenishment, and the anticipated risk of side-effects or intolerance. Intravenous iron preparations are indicated for the treatment of iron deficiency when oral preparations are ineffective or cannot be used, and therefore have applicability in a wide range of clinical contexts, including chronic inflammatory conditions, perioperative settings, and disorders associated with chronic blood loss. Adverse events occurring with intravenous iron can be anticipated according to when they typically occur, which provides a basis for educating and preparing staff and patients on how iron infusions can be administered safely and efficiently.

Nutrition-specific interventions for preventing and controlling anaemia throughout the life cycle: an overview of systematic reviews

BACKGROUND

Anaemia is a prevalent health problem worldwide. Some types are preventable or controllable with iron supplementation (pills or drops), fortification (sprinkles or powders containing iron added to food) or improvements to dietary diversity and quality (e.g. education or counselling).

OBJECTIVES

To summarise the evidence from systematic reviews regarding the benefits or harms of nutrition-specific interventions for preventing and controlling anaemia in anaemic or non-anaemic, apparently healthy populations throughout the life cycle.

METHODS

In August 2020, we searched MEDLINE, Embase and 10 other databases for systematic reviews of randomised controlled trials (RCTs) in anaemic or non-anaemic, apparently healthy populations. We followed standard Cochrane methodology, extracting GRADE ratings where provided. The primary outcomes were haemoglobin (Hb) concentration, anaemia, and iron deficiency anaemia (IDA); secondary outcomes were iron deficiency (ID), severe anaemia and adverse effects (e.g. diarrhoea, vomiting).

MAIN RESULTS

We included 75 systematic reviews, 33 of which provided GRADE assessments; these varied between high and very low. Infants (6 to 23 months; 13 reviews) Iron supplementation increased Hb levels and reduced the risk of anaemia and IDA in two reviews. Iron fortification of milk or cereals, multiple-micronutrient powder (MMNP), home fortification of complementary foods, and supplementary feeding increased Hb levels and reduced the risk of anaemia in six reviews. In one review, lipid-based nutrient supplementation (LNS) reduced the risk of anaemia. In another, caterpillar cereal increased Hb levels and IDA prevalence. Food-based strategies (red meat and fortified cow's milk, beef) showed no evidence of a difference (1 review). Preschool and school-aged children (2 to 10 years; 8 reviews) Daily or intermittent iron supplementation increased Hb levels and reduced the risk of anaemia and ID in two reviews. One review found no evidence of difference in Hb levels, but an increased risk of anaemia and ID for the intermittent regime. All suggested that zinc plus iron supplementation versus zinc alone, multiple-micronutrient (MMN)-fortified beverage versus control, and point-of-use fortification of food with iron-containing micronutrient powder (MNP) versus placebo or no intervention may increase Hb levels and reduce the risk of anaemia and ID. Fortified dairy products and cereal food showed no evidence of a difference on the incidence of anaemia (1 review). Adolescent children (11 to 18 years; 4 reviews) Compared with no supplementation or placebo, five types of iron supplementation may increase Hb levels and reduce the risk of anaemia (3 reviews). One review on prevention found no evidence of a difference in anaemia incidence on iron supplementation with or without folic acid, but Hb levels increased. Another suggested that nutritional supplementation and counselling reduced IDA. One review comparing MMN fortification with no fortification observed no evidence of a difference in Hb levels. Non-pregnant women of reproductive age (19 to 49 years; 5 reviews) Two reviews suggested that iron therapy (oral, intravenous (IV), intramuscular (IM)) increased Hb levels; one showed that iron folic acid supplementation reduced anaemia incidence; and another that daily iron supplementation with or without folic acid or vitamin C increased Hb levels and reduced the risk of anaemia and ID. No review reported interventions related to fortification or dietary diversity and quality. Pregnant women of reproductive age (15 to 49 years; 23 reviews) One review apiece suggested that: daily iron supplementation with or without folic acid increased Hb levels in the third trimester or at delivery and in the postpartum period, and reduced the risk of anaemia, IDA and ID in the third trimester or at delivery; intermittent iron supplementation had no effect on Hb levels and IDA, but increased the risk of anaemia at or near term and ID, and reduced the risk of side effects; vitamin A supplementation alone versus placebo, no intervention or other micronutrient might increase maternal Hb levels and reduce the risk of maternal anaemia; MMN with iron and folic acid versus placebo reduced the risk of anaemia; supplementation with oral bovine lactoferrin versus oral ferrous iron preparations increased Hb levels and reduced gastrointestinal side effects; MNP for point-of-use fortification of food versus iron and folic acid supplementation might decrease Hb levels at 32 weeks' gestation and increase the risk of anaemia; and LNS versus iron or folic acid and MMN increased the risk of anaemia. Mixed population (all ages; 22 reviews) Iron supplementation versus placebo or control increased Hb levels in healthy children, adults, and elderly people (4 reviews). Hb levels appeared to increase and risk of anaemia and ID decrease in two reviews investigating MMN fortification versus placebo or no treatment, iron fortified flour versus control, double fortified salt versus iodine only fortified salt, and rice fortification with iron alone or in combination with other micronutrients versus unfortified rice or no intervention. Each review suggested that fortified versus non-fortified condiments or noodles, fortified (sodium iron ethylenediaminetetraacetate; NaFeEDTA) versus non-fortified soy sauce, and double-fortified salt versus control salt may increase Hb concentration and reduce the risk of anaemia. One review indicated that Hb levels increased for children who were anaemic or had IDA and received iron supplementation, and decreased for those who received dietary interventions. Another assessed the effects of foods prepared in iron pots, and found higher Hb levels in children with low-risk malaria status in two trials, but no difference when comparing food prepared in non-cast iron pots in a high-risk malaria endemicity mixed population. There was no evidence of a difference for adverse effects. Anaemia and malaria prevalence were rarely reported. No review focused on women aged 50 to 65 years plus or men (19 to 65 years plus).

AUTHORS' CONCLUSIONS

Compared to no treatment, daily iron supplementation may increase Hb levels and reduce the risk of anaemia and IDA in infants, preschool and school-aged children and pregnant and non-pregnant women. Iron fortification of foods in infants and use of iron pots with children may have prophylactic benefits for malaria endemicity low-risk populations. In any age group, only a limited number of reviews assessed interventions to improve dietary diversity and quality. Future trials should assess the effects of these types of interventions, and consider the requirements of different populations.

Anemia in Pregnancy: ACOG Practice Bulletin, Number 233

Anemia, the most common hematologic abnormality, is a reduction in the concentration of erythrocytes or hemoglobin in blood. The two most common causes of anemia in pregnancy and the puerperium are iron deficiency and acute blood loss. Iron requirements increase during pregnancy, and a failure to maintain sufficient levels of iron may result in adverse maternal-fetal consequences. The purpose of this document is to provide a brief overview of the causes of anemia in pregnancy, review iron requirements, and provide recommendations for screening and clinical management of anemia during pregnancy.

The critical roles of iron during the journey from fetus to adolescent: Developmental aspects of iron homeostasis

Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.

Iron deficiency anaemia in pregnancy: A contemporary review

Iron deficiency anaemia is a global health problem, which particularly affects pregnant women. Iron deficiency anaemia during pregnancy is associated with increased maternal and perinatal morbidity and mortality. Maternal iron deficiency may also be associated with neurocognitive deficits in infants. Iron requirements increase during pregnancy and are influenced by hepcidin, the master regulator of iron homeostasis. The enduring global burden of maternal anaemia suggests that currently employed iron supplementation strategies are suboptimal. Recent developments in our understanding of systemic and placental iron homeostasis may improve therapeutic effectiveness by altering the dose and frequency of oral iron. Intravenous iron appears to be a safe treatment to correct maternal anaemia rapidly but research on patient-centred outcomes and cost-effectiveness is needed. Future trials should be adequately powered to assess outcomes relevant to pregnant women.

Gestational iron deficiency anemia is associated with preterm birth, fetal growth restriction, and postpartum infections

OBJECTIVES

Gestational IDA has been linked to adverse maternal and neonatal outcomes, but the impact of iron supplementation on outcome measures remains unclear. Our objective was to assess the effects of gestational IDA on pregnancy outcomes and compare outcomes in pregnancies treated with either oral or intravenous iron supplementation.

METHODS

We evaluated maternal and neonatal outcomes in 215 pregnancies complicated with gestational IDA (Hb<100 g/L) and delivered in our tertiary unit between January 2016 and October 2018. All pregnancies from the same period served as a reference group (n=11,545). 163 anemic mothers received oral iron supplementation, and 52 mothers received intravenous iron supplementation.

RESULTS

Gestational IDA was associated with an increased risk of preterm birth (10.2% vs. 6.1%, p=0.009) and fetal growth restriction (FGR) (1.9% vs. 0.3%, p=0.006). The gestational IDA group that received intravenous iron supplementation had a greater increase in Hb levels compared to those who received oral medication (18.0 g/L vs. 10.0 g/L, p<0.001), but no statistically significant differences in maternal and neonatal outcomes were detected.

CONCLUSIONS

Compared to the reference group, prematurity, FGR, postpartum infections, and extended hospital stays were more common among mothers with gestational IDA, causing an additional burden on the families and the healthcare system.

Maternal Oxygen Supplementation Compared With Room Air for Intrauterine Resuscitation: A Systematic Review and Meta-analysis

IMPORTANCE

Supplemental oxygen is commonly administered to pregnant women at the time of delivery to prevent fetal hypoxia and acidemia. There is mixed evidence on the utility of this practice.

OBJECTIVE

To compare the association of peripartum maternal oxygen administration with room air on umbilical artery (UA) gas measures and neonatal outcomes.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials were searched from February 18 to April 3, 2020. Search terms included labor or obstetric delivery and oxygen therapy and fetal blood or blood gas or acid-base imbalance.

STUDY SELECTION

Studies were included if they were randomized clinical trials comparing oxygen with room air at the time of scheduled cesarean delivery or labor in patients with singleton, nonanomalous pregnancies. Studies that did not collect paired umbilical cord gas samples or did not report either UA pH or UA Pao2 results were excluded.

DATA EXTRACTION AND SYNTHESIS

Data were extracted by 2 independent reviewers. The analysis was stratified by the presence or absence of labor at the time of randomization. Data were pooled using random-effects models.

MAIN OUTCOMES AND MEASURES

The primary outcome for this review was UA pH. Secondary outcomes included UA pH less than 7.2, UA Pao2, UA base excess, 1- and 5-minute Apgar scores, and neonatal intensive care unit admission.

RESULTS

The meta-analysis included 16 randomized clinical trials (n = 1078 oxygen group and n = 974 room air group). There was significant heterogeneity among the studies (I2 = 49.88%; P = .03). Overall, oxygen administration was associated with no significant difference in UA pH (weighted mean difference, 0.00; 95% CI, -0.01 to 0.01). Oxygen use was associated with an increase in UA Pao2 (weighted mean difference, 2.57 mm Hg; 95% CI, 0.80-4.34 mm Hg) but no significant difference in UA base excess, UA pH less than 7.2, Apgar scores, or neonatal intensive care unit admissions. Umbilical artery pH values remained similar between groups after accounting for the risk of bias, type of oxygen delivery device, and fraction of inspired oxygen. After stratifying by the presence or absence of labor, oxygen administration in women undergoing scheduled cesarean delivery was associated with increased UA Pao2 (weighted mean difference, 2.12 mm Hg; 95% CI, 0.09-4.15 mm Hg) and a reduction in the incidence of UA pH less than 7.2 (relative risk, 0.63; 95% CI, 0.43-0.90), but these changes were not noted among those in labor (Pao2: weighted mean difference, 3.60 mm Hg; 95% CI, -0.30 to 7.49 mm Hg; UA pH<7.2: relative risk, 1.34; 95% CI, 0.58-3.11).

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis suggests that studies to date showed no association between maternal oxygen and a clinically relevant improvement in UA pH or other neonatal outcomes.

The effect of iron deficiency and anaemia on women's health

Iron deficiency and anaemia are global health problems and major causes of morbidity in women. Current definitions of anaemia in women are historic and have been challenged by recent data from observational studies. Menstrual loss, abnormal uterine bleeding and pregnancy put women at risk of developing iron deficiency which can result in severe fatigue, reduced exercise capacity and poor work performance. Iron deficiency and anaemia during pregnancy are associated with adverse maternal and fetal outcomes, including neurocognitive deficits in children born to iron-deficient mothers. Both iron deficiency and anaemia are common in women undergoing surgery but their association with poor outcomes remains uncertain. The enduring burden of iron deficiency and anaemia in women suggests that current strategies for recognition, prevention and treatment are limited in their utility. Improvements in our understanding of iron homeostasis and the development of new iron preparations, which are better absorbed with fewer side-effects, may improve therapeutic effectiveness of oral iron. Intravenous iron is efficacious for correcting anaemia rapidly but high-quality data on patient-centred outcomes and cost-effectiveness are currently lacking. Many recommendations for the treatment of iron deficiency and anaemia in national guidelines are not supported by high-quality evidence. There is a need for robust epidemiological data and well-designed clinical trials. The latter will require collaborative working between researchers and patients to design studies in ways that incorporate patients' perspectives on the research process and target outcomes that matter to them.

Prediction of anemia at delivery

We aimed to assess risk factors for anemia at delivery by conducting a secondary analysis of a prospective cohort study database including 1527 women who delivered vaginally ≥ 36 gestational weeks. Anemia (Hemoglobin (Hb) < 10.5 g/dL) was assessed at delivery. A complete blood count results during pregnancy as well as maternal and obstetrical characteristics were collected. The primary endpoint was to determine the Hb cutoff between 24 and 30 gestational weeks that is predictive of anemia at delivery by using the area under the curve (AUC) of the receiver operating characteristic curve. Independent risk factors for anemia at delivery were assessed using stepwise multivariable logistic regression. Hb and infrequent iron supplement treatment were independent risk factors for anemia at delivery (OR 0.3 95%CI [0.2–0.4] and OR 2.4 95%CI [1.2–4.8], respectively; C statistics 83%). Hb 10.6 g/dL was an accurate cutoff to predict anemia at delivery (AUC 80% 95%CI 75–84%; sensitivity 75% and specificity 74%). Iron supplement was beneficial to prevent anemia regardless of Hb value. Altogether, Hb should be routinely tested between 24 and 30 gestational weeks to screen for anemia. A flow chart for anemia screening and treatment during pregnancy is proposed in the manuscript.

Trial registration: ClinicalTrials.gov Identifier: NCT02434653.

Preoperative intravenous iron for anaemia in elective major open abdominal surgery: the PREVENTT RCT

BACKGROUND

Anaemia affects 30-50% of patients before they undergo major surgery. Preoperative anaemia is associated with increased need for blood transfusion, postoperative complications and worse patient outcomes after surgery. International guidelines support the use of intravenous iron to correct anaemia in patients before surgery. However, the use of preoperative intravenous iron for patient benefit has not been assessed in the setting of a formal clinical trial.

OBJECTIVES

To assess if intravenous iron given to patients with anaemia before major abdominal surgery is beneficial by reducing transfusion rates, postoperative complications, hospital stay and re-admission to hospital, and improving quality of life outcomes.

DESIGN

A multicentre, double-blinded, randomised, controlled, Phase III clinical trial, with 1 : 1 randomisation comparing placebo (normal saline) with intravenous iron (intravenous ferric carboxymaltose 1000 mg). Randomisation and treatment allocation were by a secure web-based service.

SETTING

The study was conducted across 46 hospitals in England, Scotland and Wales between September 2013 and September 2018.

PARTICIPANTS

Patients aged > 18 years, undergoing elective major open abdominal surgery, with anaemia [Hb level of > 90 g/l and < 120 g/l (female patients) and < 130 g/l (male patients)] who could undergo randomisation and treatment 10-42 days before their operation.

INTERVENTION

Double-blinded study comparing placebo of normal saline with 1000 mg of ferric carboxymaltose administered 10-42 days prior to surgery.

MAIN OUTCOME MEASURES

Co-primary end points were risk of blood transfusion or death at 30 days postoperatively, and rate of blood transfusions at 30 days post operation.

RESULTS

A total of 487 patients were randomised (243 given placebo and 244 given intravenous iron), of whom 474 completed the trial and provided data for the analysis of the co-primary end points. The use of intravenous iron increased preoperative Hb levels (mean difference 4.7 g/l, 95% confidence interval 2.7 to 6.8 g/l; p < 0.0001), but had no effect compared with placebo on risk of blood transfusion or death (risk ratio 1.03, 95% confidence interval 0.78 to 1.37; p = 0.84; absolute risk difference +0.8%, 95% confidence interval -7.3% to 9.0%), or rates of blood transfusion (rate ratio 0.98, 95% confidence interval 0.68 to 1.43; p = 0.93; absolute rate difference 0.00, 95% confidence interval -0.14 to 0.15). There was no difference in postoperative complications or hospital stay. The intravenous iron group had higher Hb levels at the 8-week follow-up (difference in mean 10.7 g/l, 95% confidence interval 7.8 to 13.7 g/l; p < 0.0001). There were a total of 71 re-admissions to hospital for postoperative complications in the placebo group, compared with 38 re-admissions in the intravenous iron group (rate ratio 0.54, 95% confidence interval 0.34 to 0.85; p = 0.009). There were no differences between the groups in terms of mortality (two per group at 30 days post operation) or in any of the prespecified safety end points or serious adverse events.

CONCLUSIONS

In patients with anaemia prior to elective major abdominal surgery, there was no benefit from giving intravenous iron before the operation.

FUTURE WORK

The impact of iron repletion on recovery from postoperative anaemia, and the association with reduced re-admission to hospital for complications, should be investigated.

LIMITATIONS

In the preoperative intravenous iron to treat anaemia in major surgery (PREVENTT) trial, all patients included had anaemia and only 20% had their anaemia corrected before surgery. The definition and causality of iron deficiency in this setting is not clear.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN67322816 and ClinicalTrials.gov NCT01692418.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25 No. 11. See the NIHR Journals Library website for further project information.

Role of preoperative intravenous iron therapy to correct anemia before major surgery: a systematic review and meta-analysis

BACKGROUND

Preoperative anemia is a common comorbidity that often necessitates allogeneic blood transfusion (ABT). As there is a risk associated with blood transfusions, preoperative intravenous iron (IV) has been proposed to increase the hemoglobin to reduce perioperative transfusion; however, randomized controlled trials (RCT) investigating this efficacy for IV iron are small, limited, and inconclusive. Consequently, a meta-analysis that pools these studies may provide new and clinically useful information.

METHODS/DESIGN

Databases of MEDLINE, EMBASE, EBM Reviews; Cochrane-controlled trial registry; Scopus; registries of health technology assessment and clinical trials; Web of Science; ProQuest Dissertations and Theses; Clinicaltrials.gov; and Conference Proceedings Citation Index-Science (CPCI-S) were searched. Also, we screened all the retrieved reference lists.

SELECTION CRITERIA

Titles and abstracts were screened for relevance (i.e., relevant, irrelevant, or potentially relevant). Then, we screened full texts of those citations identified as potentially applicable.

RESULTS

Our search found 3195 citations and ten RCTs (1039 participants) that met our inclusion criteria. Preoperative IV iron supplementation significantly decreases ABT by 16% (risk ratio (RR): 0.84, 95% confidence interval [CI]: 0.71, 0.99, p = 0.04). In addition, preoperatively, hemoglobin levels increased after receiving IV iron (mean difference [MD] between the study groups: 7.15 g/L, 95% CI: 2.26, 12.04 g/L, p = 0.004) and at follow-up >  4 weeks postoperatively (MD: 6.46 g/L, 95% CI: 3.10, 9.81, p = 0.0002). Iron injection was not associated with increased incidence of non-serious or serious adverse effects across groups (RR: 1.13, 95% CI: 0.78, 1.65, p = 0.52) and (RR: 0.96, 95% CI: 0.44, 2.10, p = 0.92) respectively.

CONCLUSIONS

With moderate certainty, due to the high risk of bias in some studies in one or two domains, we found intravenous iron supplementation is associated with a significant decrease in the blood transfusions rate, and modest hemoglobin concentrations rise when injected pre-surgery compared with placebo or oral iron supplementation. However, further full-scale randomized controlled trials with robust methodology are required. In particular, the safety, quality of life, and cost-effectiveness of different intravenous iron preparations require further evaluation.

Safety of rapid injection of undiluted ferric carboxymaltose to patients with iron-deficiency anaemia: a Phase II single-arm study

BACKGROUND

Ferric carboxymaltose is increasingly utilised to treat iron deficiency and is usually diluted in saline and administered as an intravenous infusion over 15 min. Although this is highly convenient compared with older formulations, we hypothesised the drug could be administered, safely given as a rapid bolus injection.

AIMS

To define the risk of serious adverse events following administration of an undiluted, rapid, high-dose ferric carboxymaltose injection. Secondary aims included all other adverse events, as well as longitudinal effects on haemoglobin, iron stores, phosphate and hepcidin.

METHODS

In a single-arm, Phase II study in 121 patients with iron-deficiency anaemia, we administered up to 1000 mg of ferric carboxymaltose as a rapid undiluted bolus injection, and recorded adverse events and collected blood samples over the first hour, and again at 2 and 4 weeks post-treatment.

RESULTS

No patient experienced a serious adverse event. Flushing during the injection was common, as was a transient headache in the subsequent weeks. One patient experienced Grade 3 chest tightness, necessitating emergency department assessment but not admission or treatment. Treatment produced an average 12.3 g/L improvement in haemoglobin within 2 weeks, but commonly caused reductions in serum phosphate (although none of these was clinically symptomatic). Parenteral iron caused elevations in hepcidin sustained to 4 weeks post-injection. Patients stated they would be prepared to receive the treatment again.

CONCLUSION

Rapid injection of undiluted ferric carboxymaltose is well tolerated and could provide an approach to treat patients in the ambulatory setting.

Iron deficiency

Iron deficiency is one of the leading contributors to the global burden of disease, and particularly affects children, premenopausal women, and people in low-income and middle-income countries. Anaemia is one of many consequences of iron deficiency, and clinical and functional impairments can occur in the absence of anaemia. Iron deprivation from erythroblasts and other tissues occurs when total body stores of iron are low or when inflammation causes withholding of iron from the plasma, particularly through the action of hepcidin, the main regulator of systemic iron homoeostasis. Oral iron therapy is the first line of treatment in most cases. Hepcidin upregulation by oral iron supplementation limits the absorption efficiency of high-dose oral iron supplementation, and of oral iron during inflammation. Modern parenteral iron formulations have substantially altered iron treatment and enable rapid, safe total-dose iron replacement. An underlying cause should be sought in all patients presenting with iron deficiency: screening for coeliac disease should be considered routinely, and endoscopic investigation to exclude bleeding gastrointestinal lesions is warranted in men and postmenopausal women presenting with iron deficiency anaemia. Iron supplementation programmes in low-income countries comprise part of the solution to meeting WHO Global Nutrition Targets.

Patient Factors Associated with Prescribing of Iron for IV Administration: A Descriptive Study

BACKGROUND

IV administration of iron is appropriate for the treatment of iron deficiency anemia (IDA) when orally administered iron has not been effective, tolerated, or clinically appropriate. In Calgary, Alberta, high levels of IV iron utilization required review, because of significant health care resource utilization, high cost, and reduced accessibility.

OBJECTIVES

The primary objective was to describe the population of adult patients in Calgary with estimated glomerular filtration rate greater than or equal to 30 mL/min/1.73 m² for whom IV iron was dispensed from acute care facilities, in terms of pretreatment laboratory data, previous use of oral iron, and treatment location, as well as to characterize dose and product selection for IV iron. The secondary objective was to determine the proportion of inpatients whose treatment was in alignment with the Toward Optimized Practice clinical practice guideline for IDA.

METHODS

A retrospective review of electronic charts was used to obtain data about patients with a first dose of IV iron dispensed in Calgary hospitals between March 1 and December 31, 2018. The data were analyzed descriptively.

RESULTS

A total of 1352 patients met the inclusion criteria. These patients received a total of 3532 doses of IV iron, 97.1% of which were iron sucrose, at a median of 300 mg per infusion. Laboratory indices assessed before the first infusion were hemoglobin (mean 92, standard deviation [SD] 19.6 g/L), mean corpuscular volume (mean 81 [SD 10.3] fL), and ferritin (median 18 [interquartile range 9-48] μg/L). Among the included patients, 233 (17.2%) had oral iron dispensed within 90 days before their first IV dose of iron. Only 146 (20.1%) of the 726 inpatients had treatment that was in alignment with the Toward Optimized Practice IDA guideline.

CONCLUSIONS

There was substantial variation in baseline hemoglobin, mean corpuscular volume, and ferritin, and in the use of oral iron before initiation of IV iron treatment. Provision of educational tools and stewardship initiatives may help in ensuring alignment of iron prescribing with current guidelines.

Preoperative intravenous iron to treat anaemia before major abdominal surgery (PREVENTT): a randomised, double-blind, controlled trial

BACKGROUND

Preoperative anaemia affects a high proportion of patients undergoing major elective surgery and is associated with poor outcomes. We aimed to test the hypothesis that intravenous iron given to anaemic patients before major open elective abdominal surgery would correct anaemia, reduce the need for blood transfusions, and improve patient outcomes.

METHODS

In a double-blind, parallel-group randomised trial, we recruited adult participants identified with anaemia at preoperative hospital visits before elective major open abdominal surgery at 46 UK tertiary care centres. Anaemia was defined as haemoglobin less than 130 g/L for men and 120 g/L for women. We randomly allocated participants (1:1) via a secure web-based service to receive intravenous iron or placebo 10-42 days before surgery. Intravenous iron was administered as a single 1000 mg dose of ferric carboxymaltose in 100 mL normal saline, and placebo was 100 mL normal saline, both given as an infusion over 15 min. Unblinded study personnel prepared and administered the study drug; participants and other clinical and research staff were blinded to treatment allocation. Coprimary endpoints were risk of the composite outcome of blood transfusion or death, and number of blood transfusions from randomisation to 30 days postoperatively. The primary analysis included all randomly assigned patients with data available for the primary endpoints; safety analysis included all randomly assigned patients according to the treatment received. This study is registered, ISRCTN67322816, and is closed to new participants.

FINDINGS

Of 487 participants randomly assigned to placebo (n=243) or intravenous iron (n=244) between Jan 6, 2014, and Sept 28, 2018, complete data for the primary endpoints were available for 474 (97%) individuals. Death or blood transfusion occurred in 67 (28%) of the 237 patients in the placebo group and 69 (29%) of the 237 patients in the intravenous iron group (risk ratio 1·03, 95% CI 0·78-1·37; p=0·84). There were 111 blood transfusions in the placebo group and 105 in the intravenous iron group (rate ratio 0·98, 95% CI 0·68-1·43; p=0·93). There were no significant differences between the two groups for any of the prespecified safety endpoints.

INTERPRETATION

Preoperative intravenous iron was not superior to placebo to reduce need for blood transfusion when administered to patients with anaemia 10-42 days before elective major abdominal surgery.

FUNDING

UK National Institute of Health Research Health Technology Assessment Program.

Retrospective Evaluation of Effects of Preoperative Anaemia Treatment in Gynaecological and Obstetric Surgical Patients

Objective

In anemic patients undergoing surgery, there is an increase in the requirement of blood transfusion, longer hospital stay and higher intensive care unit adimission. In this study we aimed to evaluate the efficacy of iv iron treatment before elective obstetric or gynecological operations retrospectively.

Methods

After obtaining approval of ethics committee, records of 5688 patients underwent either obstetric or gynecological surgery between January 1st of 2016 to December 31st of 2018 were documented retrospectively and 241 anemic cases were identified. Eighty-one anemic patients who did not receive any iv iron treatment preoperatively were excluded and 160 cases treated with either iv iron (either sucrose or ferric carboxy maltose) were included. The laboratory results including haemoglobin (Hb), MCV,MCH and serum iron binding capacities, ferritin, iron and transferrin levels were documented before (preoperative) and after iv iron treatment (postoperative 10^th day) were collected from files. Difference between preoperative and postoperative Hb, MCV, MCH, TIBC, serum ferritin, iron and transferrin levels of these cases were determined.

Results

In 97 obstetric cases, the differences of Hb, MCV, MCH, serum iron, ferritin, iron binding capacity values before surgery and postoperative 10^th day were respectively found as 1.3 g dL^-1 (p=0.000); 1.9 fL (p=0.000); 0.3 pg (p=0.01); 44.4 μg dL^-1 (p=0.008); 85.9 μg L^-1 (p=0.009); 211.7 μg dL^-1 (p=0.001). In 63 gynecologic cases, same measurements were evaluated and similar differences in Hb, MCV, MCH, serum ferritin and transferrin saturation values were 1.25 g dL^-1 (p=0.000); 2.2 fL (p=0.000); 0.8 pg (p=0.000); 215.6 μg L^-1 (p=0.002); 41.5% (p=0.044). Two obstetric patients and 7 gynaecologic patients were transfused erytrocyte suspensions after surgery.

Conclusion

Efficacy of preoperative iv iron therapy in gynaecologic-obstetric patients with IDA has been demonstrated and its importance has been revisited once again.

Early intravenous iron administration in the Emergency Department reduces red blood cell unit transfusion, hospitalisation, re-transfusion, length of stay and costs

BACKGROUND

Moderate to severe iron deficiency anaemia is a common finding in patients admitted to the Emergency Department (ED). According to Patient Blood Management principles, intravenous iron should be the therapy of choice instead of blood transfusion for selected cases affected by chronic iron deficiency anaemia. However, this option is only rarely taken into account by physicians in the ED. As a result, in many circumstances, treatment of iron deficiency anaemia in the ED can differ from that of the Anaemia Clinic. With the aim of reducing inappropriate transfusions, and to implement intravenous iron usage, we shared a specific protocol with the ED.

MATERIAL AND METHODS

We reviewed the medical records of all subjects admitted to the ED (n=267, Post-protocol group) with hemoglobin ≤9.0 g/dL and mean corpuscular volume <80 fL in a 13-month period, except if the massive transfusion protocol was activated, and results were compared with an equivalent Pre-protocol historical cohort (n=226).

RESULTS

In comparison with the Pre-protocol series, the number of patients transfused did not change, but the appropriateness in terms of transfusion and red blood cell volume transfused improved sharply (87.0 vs 13.3%; p<0.001) with a significant increase in intravenous iron administration (50.2 vs 4.4% of cases; p<0.001). As a positive consequence, both the time spent in the ED by patients who were then directly discharged and costs per subject treated dropped by 37.9% and 59.0%, respectively. Treatment with infusion only in comparison with transfusion only led to a statistically significant Relative Risk reduction in transfusion on the ward and post-discharge transfusion of 55.6% and 44.4%, respectively.

DISCUSSION

The implementation of Patient Blood Management principles and early intravenous iron therapy in the Emergency Department have proved to be effective tools to optimise resources both in terms of units transfused and costs.

Iron Deficiency and Iron Deficiency Anemia: Implications and Impact in Pregnancy, Fetal Development, and Early Childhood Parameters

A normal pregnancy consumes 500–800 mg of iron from the mother. Premenopausal women have a high incidence of marginal iron stores or iron deficiency (ID), with or without anemia, particularly in the less developed world. Although pregnancy is associated with a “physiologic” anemia largely related to maternal volume expansion; it is paradoxically associated with an increase in erythrocyte production and erythrocyte mass/kg. ID is a limiting factor for this erythrocyte mass expansion and can contribute to adverse pregnancy outcomes. This review summarizes erythrocyte and iron balance observed in pregnancy; its implications and impact on mother and child; and provides an overview of approaches to the recognition of ID in pregnancy and its management, including clinically relevant questions for further investigation.