Iron Status, Anemia, and Iron Interventions and Their Associations with Cognitive and Academic Performance in Adolescents: A Systematic Review

In adolescents, iron-deficiency anemia is the leading cause of disability-adjusted life years lost. The World Health Organization recommends delivering iron supplementation through school-based platforms, requiring partnerships with the education sector. This anemia-reduction intervention is valued for the perceived benefits of improved learning and school performance. This article aims to systematically review the available evidence on the relationship between iron status and anemia and impacts of iron interventions on cognitive and academic performance in adolescents. Fifty studies were included: n = 26 cross-sectional and n = 24 iron-containing interventions. Our review suggests that iron status and anemia may be associated with academic performance in some contexts and that iron supplementation during adolescence may improve school performance, attention, and concentration. However, nearly all supplementation trials were judged to have moderate or high risk of bias. We did not find evidence suggesting that iron status and anemia influenced or were associated with attention, intelligence, nor memory in adolescents. Further, iron supplementation did not improve memory and recall or intelligence. Overall, more high-quality research is needed to guide programmers and policy makers to understand the relationships between anemia and educational performance and the potential impacts of iron interventions, which effectively reduce anemia, on adolescents’ learning and school performance.

Ferrodeficiency and pregnancy: what to do and when to begin?

In September 2021, an online webinar took place on the most common nutritional deficiency in the world – iron deficiency. According to the WHO recommendations, women should definitely receive iron and folic acid, starting with the stage of pregravid preparation, during pregnancy and lactation. Other trace elements and vitamins during pregnancy must be substantiated by evidence of their deficiency. WHO recommendations (2017) for antenatal care indicate that daily oral iron supplementation 30–60 mg and folic acid 400 µg in pregnant women can reduce the incidence of postpartum sepsis, preterm birth and low birth weight. Daily iron supplementation 60 mg should be preferred in regions where the prevalence of anemia in pregnant women ≥ 40%. In the first and third trimesters anemia is diagnosed by Hb level < 110 g/l, in the second trimester by Hb level < 105 g/l. If anemia is detected the iron dose is doubled until Hb reaches ≥ 110 g/l, after which the prophylactic dose is resumed. Iron supplements 120 mg once a week and folic acid 2800 µg once a week are recommended if daily intake of iron supplements is not possible due to side effects, and the prevalence of anemia in pregnant women does not exceed 20%.Modern Lipofer® technology in the development of liposomal iron delivery (when iron transported by liposomes) solved the problem of low bioavailability and poor tolerance, which is inherent in most ferrum drugs. As a result, iron trapped in liposomes (liposomal iron) does not come into contact with the mucous membranes of the gastrointestinal tract, but binds to chylomicrons, which enter the blood through the lymph, where iron is freed from the liposome. This way of absorption reduces iron loss, allows using of smaller doses and helps to avoid side effects.

Low-concentration Iron Promotes Klebsiella Pneumoniae Biofilm Formation by Suppressing Succinic Acid

Background: Klebsiella pneumoniae is widely distributed in water and plays a major role in both human and animal infections. Many K. pneumoniae strains form biofilms on various surfaces, enhancing their pathogenicity and resistance to antibiotics. New ways of inhibiting biofilm formation are needed. Iron is vital to the growth of microorganisms and the formation of biofilms due to its participation in various metabolic processes and its roles as an enzyme and protein cofactor. It is also present in groundwater. The aim of this study was to examine the effects of iron on K. pneumoniae biofilm formation and any associated metabolic changes.Results: Biofilm formation was enhanced to the greatest extent by the presence of 0.16 mM FeCl2, producing a denser structure under electron microscopy. The number of biofilm-forming and planktonic bacteria did not change, but protein and polysaccharide concentrations in the bacterial extracellular polymeric substances (EPS) were significantly increased by iron supplementation. To clarify this mechanism, intracellular metabolomic analysis was carried out, showing that the differential, down-regulated metabolites included succinic acid. Addition of succinic acid counteracted the biofilm-forming effect of iron, with no bactericidal side effects.Conclusion: This study demonstrates the importance of succinic acid and iron in Klebsiella pneumoniae biofilms, and provides insight into the formation of K. pneumoniae biofilms and direction for the development of new antibacterial agents.

Preoperative intravenous iron treatment reduces postoperative complications and postoperative anemia in preoperatively anemic patients with colon carcinoma

Purpose Anemia is common among patients with colorectal cancer and is associated with an increased risk of complications and poorer survival rate. The main objective of our study was to determine the effect of preoperative intravenous iron supplementation therapy on the need for red blood cell transfusions, other postoperative complications, and length of hospital stay in colon cancer patients undergoing colon resection. Methods In this retrospective cohort study, data were collected from medical records of all 549 colon carcinoma patients who underwent a colon resection in Helsinki University Hospital during the years 2017 and 2018. The patients were divided into two cohorts: one with anemic patients treated with preoperative intravenous iron supplementation therapy (180 patients) and one with anemic patients without preoperative intravenous iron supplementation therapy (138 patients). Non-anemic patients and patients requiring emergency surgery were excluded (231 patients). Results Patients treated with intravenous iron had less postoperative complications (33.9% vs. 45.9%, p = 0.045) and a lower prevalence of anemia at 1 month after surgery (38.7% vs. 65.3%, p < 0.01) when compared with patients without preoperative iv iron treatment. No difference was found in the amount of red blood cell transfusions, length of stay, or mortality between the groups. Conclusion This is the first study demonstrating a significant decrease in postoperative complications in anemic colon cancer patients receiving preoperative intravenous iron supplementation therapy. This treatment also diminishes the rate of postoperative anemia, which is often associated with a facilitated recovery.