Systematic review of guidelines for the diagnosis and treatment of iron deficiency anemia using intravenous iron across multiple indications

Iron deficiency in children with a focus on inflammatory conditions

Iron deficiency (ID) tends to be overlooked compared with anemia. However, its prevalence is estimated to be twice as high as that of ID anemia, and ID without anemia can be accompanied by clinical and functional impairments. The symptoms of ID are nonspecific, such as fatigue and lethargy, but can lead to neurodevelopmental disorders in children, restless legs syndrome, and recurrent infections due to immune system dysregulation. In particular, the risk of ID is high in the context of chronic inflammatory diseases (CIDs) due to the reaction of various cytokines and the resulting increase in hepcidin levels; ID further exacerbates these diseases and increases mortality. Therefore, the diagnosis of ID should not be overlooked through ID screening especially in high-risk groups. Ferritin and transferrin saturation levels are the primary laboratory parameters used to diagnose ID. However, as ferritin levels respond to inflammation, the diagnostic criteria differ among guidelines. Therefore, new tools and criteria for accurately diagnosing ID should be developed. Treatment can be initiated only with an accurate diagnosis. Oral iron is typically the first-line treatment for ID; however, the efficacy and safety of intravenous iron have recently been recognized. Symptoms improve quickly after treatment, and the prognosis of accompanying diseases can also be improved. This review highlights the need to improve global awareness of ID diagnosis and treatment, even in the absence of anemia, to improve the quality of life of affected children, especially those with CIDs.

Appropriateness of inpatient intravenous iron therapy in a Swiss tertiary care hospital

INTRODUCTION

Intravenous (IV) iron replacement is an established treatment for iron deficiency and is recommended in various medical guidelines, but cheaper oral iron formulations remain first-line therapy in several instances. Data on adherence to current prescription standards are lacking in Switzerland.

METHODS

Retrospective single center quality control study evaluating the appropriateness of IV iron replacement in 400 inpatients during 2019 and 2021 at a Swiss tertiary care hospital. Appropriateness of IV iron was assessed by expert chart review according to national and international guidelines.

RESULTS

IV iron prescriptions were assessed as inappropriate in 147 (37%) of cases (indication lacking in 13%, oral route preferred in 24%). Inappropriate prescribing was more common (p < .001) in surgical wards (66%) compared to medical units (48%) and the gynecologic ward (19%). Iron studies were lacking in 29% of inappropriate IV administrations. Insufficient replacement dosages were chosen in 38% of patients with appropriate prescription.

CONCLUSION

Based on current guidelines, inappropriate in-hospital prescription of IV iron was frequently observed. Considerable differences exist between hospital units, which are consistent with conflicting recommendations of professional societies. We recommend increased attention toward the prescription quality to avoid unnecessary, expensive, and potentially harmful use of IV iron.

Disutilities Associated with Intravenous Iron Infusions: Results from a Time Trade-off Survey and Diminishing Marginal Utility Model for Treatment Attributes in China

Purpose

Treatment process attributes can affect health state utilities associated with therapy. For intravenous iron, used to treat iron deficiency and iron deficiency anemia, research into process attributes is still lacking. This study estimated utilities associated with process attributes for intravenous iron infusions.

Methods

An online survey including seven health state vignettes and time trade-off tasks was administered to participants, who were not patients living with iron deficiency or iron deficiency anemia, from a Chinese online panel. Vignettes used an identical description of iron deficiency and iron deficiency anemia but differed in the annual number of infusions, infusion duration, and infusion-associated risk of hypophosphatemic osteomalacia. Disutilities and their rate of change as the number of infusions increased were examined using a power model.

Results

The survey was completed by 1091 participants. The highest utilities were observed for one annual infusion of 15-30 minutes or 30-60 minutes, without risk of hypophosphatemic osteomalacia (0.754 and 0.746, respectively). In comparison, more infusions and infusions with a risk of hypophosphatemic osteomalacia were associated with lower utilities. Utility continued to decrease, but at a diminishing rate, as the annual number of infusions increased, with utility decrements of 0.006 and 0.002, respectively, when going from zero to one and from four to five infusions per year. All marginal disutilities were small (values <0.01).

Conclusion

This study suggested that treatment attributes of intravenous iron infusions affect health state utilities. Using intravenous iron formulations that allow for fewer and shorter infusions without the risk of hypophosphatemic osteomalacia can reduce the number of visits required and increase patients' quality of life.

Prevention and Management of Iron Deficiency/Iron-Deficiency Anemia in Women: An Asian Expert Consensus

The lack of standardized clinical practice impeding the optimal management of iron deficiency (ID) and iron deficiency anemia (IDA) in women is a global concern, particularly in the Asia-Pacific region. The aim of this study was to determine best practices through a Delphi consensus process. In Round 1, panelists were asked to rate their level of agreement with 99 statements across four domains: identification, diagnosis and assessment, prevention, and treatment of ID/IDA in women. In Round 2, panelists reappraised their ratings in view of the collective feedback and responses to Round 1. After two rounds, consensus (≥85% agreement) was reached for 84% of the Delphi statements. Experts agreed on the role of presenting symptoms and risk factors in prompting assessments of anemia and iron status in women. Experts repeatedly called for prevention, recommending preventive iron supplementation for pregnant women irrespective of anemia prevalence levels, and for non-pregnant adult women, adolescent girls, and perimenopausal women living in areas with a high prevalence of anemia. Experts unanimously agreed to prescribing oral ferrous iron as first-line therapy for uncomplicated ID/IDA. The recommendations and clinical pathway algorithms generated should be used to inform clinical practice and standardize the care of women at risk or presenting with ID/IDA in the Asia-Pacific region.

High-risk fertility behaviour and childhood anaemia in sub-Saharan Africa

OBJECTIVE

This study sought to examine the association between high-risk fertility behaviour and childhood anaemia in sub-Saharan Africa .

DESIGN

An analytical study was conducted using cross-sectional data from mothers with children under age 5 (n=64 512) from 28 sub-Saharan African countries. Multilevel logistic regression models were fitted to examine the association between high-risk fertility behaviour and childhood anaemia. The results were presented using adjusted odds ratios (aORs) with 95% confidence interval (CI).

SETTING

Twenty-eight sub-Saharan African countries.

OUTCOME MEASURE

Childhood anaemia.

RESULTS

The percentage of children with anaemia in the 28 countries was 66.7%. We found that age more than 34 at delivery and short birth interval had significant associations with childhood anaemia. Children of mothers whose most recent delivery occurred after 34 years were less likely to be anaemic compared with those whose most recent delivery occurred before age 34 (aOR=0.89; 95% CI 0.83 to 0.95). We found that children born to mothers with short birth intervals were more likely to be anaemic, compared with those with long birth intervals (aOR=1.08; 95% CI 1.01 to 1.16).

CONCLUSIONS

We, therefore, draw the attention of policy makers and programme implementers to invest in policies and programmes aimed at combating childhood anaemia in sub-Saharan Africa to focus on the population at risk, that is, women whose most recent delivery occurred at younger ages and those with short birth intervals. Encouraging contraceptive use and creating awareness about the importance of birth spacing among reproductive-age women would be more helpful.

The Evaluation Of Iron Deficiency And Iron Overload

BACKGROUND

In the western world, 2-5% of women of child-bearing age suffer from irondeficiency anemia. Iron overload due to chronic treatment with blood transfusions or hereditary hemochromatosis is much rarer.

METHODS

This review is based on pertinent publications retrieved by a selective search on the pathophysiology, clinical features, and diagnostic evaluation of iron deficiency and iron overload.

RESULTS

The main causes of iron deficiency are malnutrition and blood loss. Its differential diagnosis includes iron-refractory iron deficiency anemia (IRIDA), a rare congenital disease in which the hepcidin level is pathologically elevated, as well as the more common anemia of chronic disease (anemia of chronic inflammation), in which increased amounts of hepcidin are formed under the influence of interleukin-6 and enteric iron uptake is blocked as a result. Iron overload comes about through long-term transfusion treatment or a congenital disturbance of iron metabolism (hemochromatosis). Its diagnostic evaluation is based on clinical and laboratory findings, imaging studies, and specific mutation analyses.

CONCLUSION

Our improving understanding of the molecular pathophysiology of iron metabolism aids in the evaluation of iron deficiency and iron overload and may in future enable treatment not just with iron supplementation or iron chelation, but also with targeted pharmacological modulation of the hepcidin regulatory system.

Risk of Infection Associated With Administration of Intravenous Iron: A Systematic Review and Meta-analysis

IMPORTANCE

Intravenous iron is recommended by many clinical guidelines based largely on its effectiveness in reducing anemia. However, the association with important safety outcomes, such as infection, remains uncertain.

OBJECTIVE

To examine the risk of infection associated with intravenous iron compared with oral iron or no iron.

DATA SOURCES

Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for randomized clinical trials (RCTs) from 1966 to January 31, 2021. Ongoing trials were sought from ClinicalTrials.gov, CENTRAL, and the World Health Organization International Clinical Trials Search Registry Platform.

STUDY SELECTION

Pairs of reviewers identified RCTs that compared intravenous iron with oral iron or no iron across all patient populations, excluding healthy volunteers. Nonrandomized studies published since January 1, 2007, were also included. A total of 312 full-text articles were assessed for eligibility.

DATA EXTRACTION AND SYNTHESIS

Data extraction and risk of bias assessments were performed according to the Preferred Reporting Items of Systematic Reviews and Meta-analyses (PRISMA) and Cochrane recommendations, and the quality of evidence was assessed using the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) approach. Two reviewers extracted data independently. A random-effects model was used to synthesize data from RCTs. A narrative synthesis was performed to characterize the reporting of infection.

MAIN OUTCOMES AND MEASURES

The primary outcome was risk of infection. Secondary outcomes included mortality, hospital length of stay, and changes in hemoglobin and red blood cell transfusion requirements. Measures of association were reported as risk ratios (RRs) or mean differences.

RESULTS

A total of 154 RCTs (32 920 participants) were included in the main analysis. Intravenous iron was associated with an increased risk of infection when compared with oral iron or no iron (RR, 1.17; 95% CI, 1.04-1.31; I2 = 37%; moderate certainty of evidence). Intravenous iron also was associated with an increase in hemoglobin (mean difference, 0.57 g/dL; 95% CI, 0.50-0.64 g/dL; I2 = 94%) and a reduction in the risk of requiring a red blood cell transfusion (RR, 0.93; 95% CI, 0.76-0.89; I2 = 15%) when compared with oral iron or no iron. There was no evidence of an effect on mortality or hospital length of stay.

CONCLUSIONS AND RELEVANCE

In this large systematic review and meta-analysis, intravenous iron was associated with an increased risk of infection. Well-designed studies, using standardized definitions of infection, are required to understand the balance between this risk and the potential benefits.

Dose effect of bovine lactoferrin fortification on diarrhea and respiratory tract infections in weaned infants with anemia: A randomized, controlled trial

OBJECTIVE

The aim of this study was to explore the dose effect of bovine lactoferrin (bLF) fortification on the morbidity of diarrhea and respiratory tract infections in weaned infants with anemia.

METHODS

A total of 108 infants with anemia, who were exclusively breast fed at 4 to 6 mo and weaned and formula fed at 6 to 9 mo, were recruited. The eligible infants were randomly assigned to fortified group 0 (FG0), fortified group 1 (FG1), or fortified group 2 (FG2) and were given formula fortified with 0 mg/100 g, 38 mg/100 g, and 76 mg/100 g of bLF, respectively, for 3 mo. The morbidity of diarrhea and respiratory tract infections (RTIs), the duration of respiratory and diarrhea-related illnesses, and the levels of fecal human beta-defensin 2 (HBD-2), cathelicidin LL-37 (LL-37), secretory IgA (sIgA), butyrate, and calprotectin were assessed.

RESULTS

After the exclusion of 12 dropouts, the primary outcome measures, including episodes and duration of diarrhea and RTIs during the intervention, were obtained from 96 infants (35, 33, and 28 in FG0, FG1, and FG2, respectively). Compared with infants in FG0, there was a lower morbidity of rhinorrhea, wheezing, and skin rash among infants in FG1 (P < 0.05) and a lower morbidity of respiratory-related illness and wheezing among infants in FG2 (P < 0.05). Furthermore, a lower morbidity of diarrhea-related illness, diarrhea, vomiting, and nausea was observed among infants in FG2 than those in the other two groups (P < 0.05). In addition, the FG1 infants had a lower morbidity of vomiting and nausea than the FG0 infants (P < 0.05). The HBD-2, LL-37, sIgA, and calprotectin levels were significantly higher whereas the butyrate level was significantly lower in the FG2 infants than in infants in the other two groups after 3 mo of intervention (P < 0.05).

CONCLUSIONS

The bLF-fortified formula was effective in reducing the morbidity of diarrhea and RTIs in infants with anemia, with the 76 mg/100 g bLF-fortified formula exhibiting a stronger effect. The bLF fortification could be a new strategy for the prevention of diarrhea and RTIs in infants with anemia.

[CME-Laboratory 63: Diagnostics of Iron Metabolism]

CME-Laboratory 63: Diagnostics of Iron Metabolism Abstract. Iron deficiency is common and affects the course of many chronic diseases. The diagnosis of absolute and manifest iron deficiency anemia can be easily made by measuring hemoglobin and serum ferritin levels. In inflammatory diseases, the diagnosis can be facilitated by additional laboratory parameters such as soluble transferrin receptor. In several chronic diseases like cardiac or renal failure, different and higher thresholds for serum ferritin apply depending on the disease and stage, sometimes with additional consideration of transferrin saturation. Transferrin saturation is also important for the diagnosis of hemochromatosis. In patients with transferrin saturation >45 %, diagnosis usually requires evidence of homozygosity for the C282Y mutation in the HFE gene.