Chinese physician perception on the treatment of chemotherapy-induced anemia: online cross-section survey study.

BACKGROUND: The management of chemotherapy induced anemia (CIA) remains challenging. The potential risk and benefits in providing patient-centered care need to be balanced; the disease is multifactorial; and the major treatments including red blood cell (RBC) transfusions, erythropoiesis-stimulating agents (ESAs) and intravenous injection (i.v.)iron supplementation have a unique set of strengths and limitations. Also, most previous survey based on the patient data could not reveal the process of evaluation and decision-making for CIA treatment from a physician's perspective. As the comparison of China Society of Clinical Oncology (CSCO), National Comprehensive Cancer Network (NCCN) and European Society of Medical Oncology (ESMO) guidelines, the standard of CIA treatment in China will vary from United States and Europe, for example, the initial hemoglobin (Hb) for RBC transfusions. In order to understand the diagnosis, treatment, and unmet medical needs of CIA patients, the China Medical Education Association (CMEA), in conjunction with Cancer Hope Medium, initiated the first national survey of Chinese physicians regarding the diagnosis and treatment of CIA. METHODS: The CMEA sent an online, 12-item questionnaire (via wjx.cn) to physicians across China from September 1, 2022 to October 22, 2022. Two hundred and sixty-five samples were calculated usingsurveyplanet.com. The questionnaire evaluated the impact of anemia on chemotherapy interruption, initial treatment, the target Hb level of CIA in, and the current status of ESAs prescription in clinical practice. Respondents were asked to score their reasons for not using ESAs (including safety issues, drug access in practice or adherence) and the risk options of the current treatment including ESAs, RBC transfusion, and i.v.iron. RESULTS: A total of 331 questionnaires among 5,000 web visits were gathered, covering 247 hospitals in 29 provinces across China, of which 130 (53%) were tier IIIA hospitals, 50 (20%) were tier III B hospitals, 59 (24%) were tier IIA hospitals, and 8 (3%) were tier II B hospitals. The frequency of chemotherapy dose delay/reduction due to anemia was 24% [standard deviation (SD) 49%]. Most responding physicians rated an initial Hb level for ESAs treatment to be 80 g/L, with a favorable Hb level for chemotherapy being 100 g/L (60%), which would not limit treatment availability. The majority (67.6%, n=221) of physicians who responded indicated that they had used ESAs for anemia correction, while the others (32.4%, n=106) reported never using them. CONCLUSIONS: This is the first study in conducting a large-scale survey on the diagnosis and treatment of CIA in China from a physicians' perspective. We found that in China, nearly one-quarter of patients undergoing chemotherapy with concurrent anemia may experience interruption of chemotherapy and that the initiation of anemia treatment is not adequately timed. In treating CIA, most physicians prioritize the completion of chemotherapy via Hb level over treating the symptoms of anemia.

Early iron supplementation in exclusively breastfed Gambian infants: a randomized controlled trial.

Objective: To investigate the effect of daily iron supplementation for 14 weeks on the serum iron concentration and other markers of iron status in exclusively breastfed infants in Gambia. Methods: A placebo-controlled, randomized, double-blind trial was performed in rural Gambia between 3 August 2021 and 9 March 2022. Overall, 101 healthy, exclusively breastfed infants aged 6 to 10 weeks were recruited at vaccination clinics and through community health workers. Infants were randomized to receive iron supplementation (7.5 mg/day as ferrous sulfate in sorbitol solution) or placebo for 98 days. Venous blood samples were collected at baseline and on day 99 to assess the serum iron concentration and other markers of iron and haematological status. Findings: At day 99, the serum iron concentration was significantly higher in the iron supplementation group than the placebo group (crude difference in means: 2.5 µmol/L; 95% confidence interval: 0.6 to 4.3) and there were significant improvements in other iron and haematological markers. There were 10 serious adverse events (five in each group), 106 non-serious adverse events (54 with iron supplementation; 52 with placebo) and no deaths. There was no marked difference between the groups in maternally reported episodes of diarrhoea, fever, cough, skin infection, eye infection or nasal discharge. Conclusion: In exclusively breastfed Gambian infants, iron supplementation from 6 weeks of age was associated with a significant improvement in markers of iron status at around 6 months of age. There was no indication of adverse effects on growth or infections.

Liproxstatin-1 alleviates ferroptosis in sevoflurane anesthesia-induced cognitive deficits of aged mice: The role oxidative stress.

In this study, we aimed to validate the hypothesis that the interplay between sevoflurane, oxidative stress and ferroptosis is crucial for the pathogenesis of sevoflurane-induced cognitive impairment in aged individuals. The mice with sevoflurane-induced cognitive impairment were used to explore the effects of sevoflurane on oxidative stress, iron homeostasis, and cognitive function in aged mice. Iron content and oxidative stress markers were analyzed in hippocampal tissue homogenates using specific assays. Additionally, the levels of iron death-related markers (Fth1 and Gpx4) were assessed by real-time PCR and Western blotting. Morris Water Maze and novel object recognition (NOR) tests were conducted to evaluate cognitive function. Sevoflurane exposure in aged mice resulted in a significant increase in iron overloading in the hippocampus, followed by a subsequent stabilization. Oxidative stress levels were elevated in the hippocampal tissue of sevoflurane-exposed mice, and a significant correlation was observed between iron death and oxidative stress. Liproxstatin-1, a ferroptosis inhibitor, effectively ameliorated the decline in memory and learning abilities induced by sevoflurane anesthesia. Liproxstatin-1 treatment reduced iron overload and oxidative stress in the hippocampal tissue of aged mice. The expression of Fth1 and Gpx4, iron death-related markers, was downregulated following Liproxstatin-1 intervention. Our findings suggest that sevoflurane anesthesia disrupts iron homeostasis, leading to increased oxidative stress and cognitive impairment in aged mice. These results highlight the potential of targeting iron-mediated processes to mitigate sevoflurane-induced cognitive impairment in the aging population.

Association between aluminum and iron exposure in maternal blood and umbilical cord blood and congenital heart defects in children.

Background: Congenital heart disease (CHDs) is the major cause of mortality from birth defects, affecting up to 1% of live births worldwide. However, the relationship between aluminum (Al) and iron (Fe) levels and the risk of CHDs has yielded inconsistent results. Methods: We conducted a pair-matched case-control study that included 97 CHDs and 194 non-CHDs to investigate the association and interaction between Al/Fe exposure and the risk of CHDs in a birth cohort study in Lanzhou, China. Results: Higher concentrations of cord blood Al were associated with a greater risk of total CHDs (aOR = 2.826, 95% CI [1.009-7.266]) and isolated CHDs (aOR = 10.713, 95% CI [1.017-112.851]) compared to the lowest Al level. Both in maternal blood and cord blood, a significant dose-effect was observed between Al level and total CHDs (Ptrend < 0.05), but a similar pattern was not observed for Fe. High Al in addition to high Fe appeared to elicit a stronger association with CHDs than both lowest tertile of Al and Fe level in umbilical cord blood, particularly for multiple CHDs, septal defects and patent ductus arteriosus. Conclusions: Our study suggests that exposure to Al during pregnancy (≥2,408 µg/L) is significantly associated with an increased risk of CHDs in offspring, especially septal defects, and that high levels of Al and Fe are strongly correlated with fetal heart development. Further research is needed to understand the underlying mechanisms.

Administration of intravenous iron through a home-based infusion strategy is safe and has high patient acceptance.

BACKGROUND AND AIMS: To evaluate the safety and patient experience of a hospital-initiated home-based iron infusion service in patients with iron deficiency with or without anaemia. METHODS: Retrospective cohort study, including adult patients who received intravenous iron through a Hospital in The Home service in a single tertiary centre between August 2020 and 2021. A chart review was conducted for documented adverse events (AEs). A telephone survey assessed patient acceptance with three questions on a 5-point Likert scale: (i) How do you perceive the experience of having your infusion given in the home? (ii) Would you like to have the infusion in the same location if you require one in the future? and (iii) Do you feel safe having your infusion at home? OUTCOME MEASURES: Percentage of patients experiencing AEs and patient acceptance of a home-based iron infusion strategy. RESULTS: One hundred ninety-seven patients were included (181 ferric carboxymaltose and 16 ferric derisomaltose). Six (3%) patients (2 of 181 patients who received ferric carboxymaltose compared with 4 of 16 patients who received ferric derisomaltose, P < 0.001, Fisher's exact) experienced AEs, mostly headache and pruritus. Most patients who participated in the telephone survey had a positive experience (57/58 (98%)), felt safe (57/58 (98%)) and preferred future infusions to occur at home (52/58 (90%)). CONCLUSION: A home-based iron infusion strategy was safe and well accepted by patients. Larger studies evaluating the safety profile of different iron formulations in the home setting are required.

Habitual intake of iron, copper, and zinc and the risk of type 2 diabetes in a prospective cohort: The CAVAS (Cardiovascular Disease Association Study).

BACKGROUND AND AIMS: Unlike iron, evidence of the association between dietary copper and zinc intake and type 2 diabetes (T2D) risk is limited. This study aimed to examine the prospective associations of dietary intake of iron (total, plant-based, and animal-based), copper, and zinc with T2D risk among adults aged ≥40 years. METHODS AND RESULTS: For 16,666 participants, dietary intakes (baseline, cumulative average, and most recent) of iron, copper, and zinc were calculated from repeated food frequency questionnaires; a modified Poisson regression model with a robust error estimator was conducted. In men, positive associations between T2D and baseline dietary intake of Cu and Zn, cumulative average dietary intake of Fe (total and animal-based), Cu and Zn, and most recent dietary intake of Fe (total, plant-based, and animal-based), Cu, and Zn [most recent diet: for total Fe, IRR(95%CI) = 1.93 (1.41-2.64); for plant-based Fe, 1.56 (1.15-2.11); for animal-based Fe, 1.44 (1.09-1.90); for Cu, 3.17 (2.33-4.30); for Zn, 2.18 (1.64-2.89)] were observed, where as in women, there were positive associations of only cumulative average dietary Zn intake and most recent dietary intake of plant-based Fe, Cu, and Zn [most recent diet: for plant-based Fe, 1.30 (1.01-1.68); for Cu, 1.62 (1.27-2.08); for Zn, 2.07 (1.61-2.66)]. CONCLUSION: Dietary intakes of iron (total, plant-based, and animal-based), copper, and zinc may be positively associated with T2D risk. These positive associations are predominantly observed in most recent diet and appear to be stronger compared to baseline and cumulative average diet.

Anemia and iron deficiency in pregnant women with rheumatic diseases.

INTRODUCTION: Anemia and iron deficiency are the most common pathologies in pregnancy and associated with adverse pregnancy outcome. As patients with rheumatic diseases are also at high risk for anemia, we aimed to investigate the frequency of anemia and iron deficiency during pregnancy in this group and whether anemia is a risk factor for adverse maternal or child outcome. METHODS: We analyzed 368 pregnancies from a German registry for pregnancies in patients with rheumatic diseases (TURIRE) from 2014-2022. Anemia and iron deficiency were defined according to the World Health Organization. Main outcome measures were prevalence of anemia, iron deficiency, and adverse outcomes. RESULTS: From the 368 patients 61% were diagnosed with a connective tissue disease, 16% with rheumatoid arthritis or juvenile idiopathic arthritis, 14% with spondyloarthritis, 3% with vasculitis and 7% with other. Prevalence of anemia/iron deficiency was 18%/28% in the first, 27%/51% in the second and 33%/62% in the third trimester. Low hemoglobin levels (OR 0.52) or iron deficiency (OR 0.86) had a negative impact on child outcome. However, lower hemoglobin levels were associated with a lower risk for maternal complications (OR 1.47). CONCLUSION: Prevalence of anemia and iron deficiency is high in pregnant women with rheumatic diseases. Compared to previously published cohorts of the general population from different countries, the prevalence of anemia and iron deficiency is distinctly higher. Furthermore, patients with rheumatic diseases already start with impaired iron storage and/or hemoglobin levels. Thus, iron supplementation should be initiated early on in this vulnerable in this patient group.

Intravenous iron: an update.

Iron deficiency is the most common nutritional deficiency worldwide, with significant adverse health consequences in the presence or absence of anaemia. Total dose intravenous iron replacement is recommended for replacement of iron in patients with severe iron deficiency, especially in the presence of anaemia, intolerance or inefficacy following oral iron, or states of inflammation where upregulation of hepcidin may impair gastrointestinal absorption of iron. Currently, available intravenous iron formulations have been demonstrated to have an excellent overall safety profile, but potential adverse effects, including skin staining, infusion-related reactions and hypophosphataemia, have been described. Knowledge of differences in administration and safety profiles of currently available iron formulations will allow appropriate prescription, counselling, as well as recognition and management of adverse events in patients requiring intravenous iron.

The Therapeutic Potential of Targeting Ferroptosis in the Treatment of Mitochondrial Cardiomyopathies and Heart Failure.

ABSTRACT: Ferroptosis is a form of iron-regulated cell death implicated in a wide array of diseases, including heart failure, hypertension, and numerous cardiomyopathies. In addition, mitochondrial dysfunction has been associated with several of these same disease states. However, the role of the mitochondrion in ferroptotic cell death remains debated. As a major regulator of cellular iron levels, the mitochondria may very well play a crucial role in the mechanisms behind ferroptosis, but at this point, this has not been adequately defined. Emerging evidence from our laboratory and others indicates a critical role of mitochondrial Sirtuin 3, a deacetylase linked with longevity and protection against numerous conditions, in the prevention of cardiovascular diseases. Here, we provide a brief overview of the potential roles of Sirtuin 3 in mitochondrial iron homeostasis and its contribution to the mitochondrial cardiomyopathy of Friedreich's ataxia and diabetic cardiomyopathy. We also discuss the current knowledge of the involvement of ferroptosis and the mitochondria in these and other cardiovascular disease states, including doxorubicin-induced cardiomyopathy, and provide insight into areas requiring further investigation.

Management of iron deficiency in women of childbearing age with oral iron intolerance: a prospective, randomised, controlled trial of three doses of an iron-whey-protein formulation : Prospective RandomisEd study of women of Childbearing age with gastroInteStinal Intolerance to Oral iroN (PRECISION).

BACKGROUND: Nutritional deficit and oral iron gastrointestinal intolerance may be a common cause of iron deficiency, which can be managed by pharmacists. AIM: To understand the prevalence of iron deficiency in women of childbearing age with a self-reported history of intolerance to oral iron and the tolerability of three doses of an iron-whey-protein formulation in the care of these women. METHOD: Ferritin and haemoglobin levels were documented in women of childbearing age with oral iron gastrointestinal intolerance. In those with iron deficiency (ferritin < 30 µg/L), adherence, gastrointestinal tolerability, ferritin, transferrin saturation and haemoglobin levels were compared between their prior oral iron product and iron-whey-protein microspheres randomised to three doses (14 mg daily, 25 mg daily and 50 mg daily) for 12 weeks. RESULTS: Most screened women had low iron stores (128 (62.7%); ferritin < 30 µg/L), 65 (31.9%) had moderate to severe iron deficiency (ferritin < 12 µg/L) and 33 (16.2%) had iron deficiency anaemia (ferritin < 30 µg/L, haemoglobin < 12 g/dL). Amongst the 59 women who participated in the prospective clinical study of iron-whey-protein microspheres over 12 weeks, 48 (81.4%) were classified as adherent/persistent and fewer instances of gastrointestinal intolerance were reported (0.59 ± 0.91) when compared to 12 (20.3%) and (4.0 ± 2.2) respectively while taking the prior oral iron (Fisher's Exact and T-test respectively, both p < 0.001). There was no difference in adherence or tolerability of different iron-whey-protein formulation doses. Ferritin, haemoglobin and energy levels increased significantly over 12 weeks. CONCLUSION: Undiagnosed iron deficiency is common in women of childbearing age with a history of intolerance to oral iron and iron-whey-protein microspheres can improve adherence, GI tolerability, iron stores, haemoglobin and energy levels in these women. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov identifier (registration includes full trial protocol): NCT04778072.

Thrombocytopenia Caused by Iron Infusion in a Patient with End-Stage Kidney Disease.

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The effect of iron therapy on oxidative stress and intestinal microbiota in inflammatory bowel diseases: A review on the conundrum.

One in five patients with Inflammatory Bowel Disease (IBD) suffers from anemia, most frequently caused by iron deficiency. Anemia and iron deficiency are associated with worse disease outcomes, reduced quality of life, decreased economic participation, and increased healthcare costs. International guidelines and consensus-based recommendations have emphasized the importance of treating anemia and iron deficiency. In this review, we draw attention to the rarely discussed effects of iron deficiency and iron therapy on the redox status, the intestinal microbiota, and the potential interplay between them, focusing on the clinical implications for patients with IBD. Current data are scarce, inconsistent, and do not provide definitive answers. Nevertheless, it is imperative to rule out infections and discern iron deficiency anemia from other types of anemia to prevent untargeted oral or intravenous iron supplementation and potential side effects, including oxidative stress. Further research is necessary to establish the clinical significance of changes in the redox status and the intestinal microbiota following iron supplementation.

The role of iron and ferroptosis in the pathogenesis of acute pancreatitis.

Acute pancreatitis (AP) is an inflammatory disease of the pancreas. Iron is an essential element for life and is involved in many metabolic processes. Ferroptosis is a type of regulated cell death that is triggered by iron and oxidative stress. A well-established mouse AP model was adopted to study the role of iron and ferroptosis in the pathogenesis of pancreatitis. Mice were injected with cerulein to induce AP, and pancreatic tissue samples were analyzed to determine the pathology, cell death, iron deposition, expression of iron transporters, and lipid peroxidation. The role of iron was studied by giving mice extra iron or iron chelator. In vitro studies with acinar cells with ferroptosis activator and inhibitor were also performed to assess the inflammatory response. Iron was found accumulated in the pancreatic tissue of mice who suffered cerulein-induced pancreatitis. Cell death and lipid peroxidation increased in these tissues and could be further modulated by iron dextran or iron chelator. Mice given Hemin through gavage had reduced levels of GSH in pancreatic tissue and increased inflammatory response. Studies with acinar cells showed increased levels of lipid peroxidation and ferroptosis-specific mitochondrial damage when treated with ferroptosis inducer and inflammatory cytokines.

Association of iron therapy with incidence of chronic kidney disease.

OBJECTIVE: We investigated the association of oral iron replacement with the incidence of chronic kidney disease (CKD) in a population with normal kidney function to study the effects of iron replacement on the development of new onset CKD. METHODS: In a national cohort of US Veterans with no pre-existing CKD, we identified 33 894 incident new users of oral iron replacement and a comparable group of 112 780 patients who did not receive any iron replacement during 2004-2018. We examined the association of oral iron replacement versus no iron replacement with the incidence of eGFR <60 mL/min/1.73 m2 and the incidence of urine albumin creatinine ratio (UACR) ≥30 mg/g in competing risk regressions and in Cox models. We used propensity score weighing to account for differences in key baseline characteristics associated with the use of oral iron replacement. RESULTS: In the cohort of 146 674 patients, a total of 18 547 (13%) patients experienced incident eGFR <60 mL/min/1.73 m2 , and 16 117 patients (11%) experienced new onset UACR ≥30 mg/g. Oral iron replacement was associated with significantly higher risk of incident eGFR <60 mL/min/1.73 m2 (subhazard ratio, 95% confidence interval [CI]: 1.3 [1.22-1.38], p < .001) and incident albuminuria (subhazard ratio, 95% CI: 1.14 [1.07-1.22], p < .001). CONCLUSION: Oral iron replacement is associated with higher risk of new onset CKD. The long-term kidney safety of oral iron replacement should be tested in clinical trials.

Incidence of Hypophosphatemia After Intravenous Administration of Iron: A Matching-Adjusted Indirect Comparison of Data from Japanese Randomized Controlled Trials.

INTRODUCTION: Intravenous (IV) administration of iron is considered a safe and efficacious treatment for iron deficiency anemia (IDA), recommended in patients requiring rapid replenishment of iron, or intolerant or unresponsive to oral administration of iron. Recent randomized controlled trials (RCTs) have shown high incidence of hypophosphatemia after administration of two IV iron preparations: saccharated ferric oxide (SFO) and ferric carboxymaltose (FCM). The present study aimed to conduct matching-adjusted indirect comparison (MAIC) of hypophosphatemia incidence with these iron formulations and ferric derisomaltose (FDI) based on data from head-to-head RCTs conducted in Japan. METHODS: A MAIC of hypophosphatemia incidence was conducted on the basis of data from two head-to-head RCTs. The relative odds of hypophosphatemia with FDI versus SFO were obtained from patient-level data from a recent RCT and adjusted for cumulative iron dose, while parametric models of serum phosphate levels from a separate RCT were used to estimate the relative odds of hypophosphatemia with FCM with SFO. An anchored MAIC was then conducted comparing FDI with FCM. RESULTS: The adjusted odds of experiencing hypophosphatemia were significantly lower with FDI than SFO [odds ratio (OR) of 0.02; 95% confidence interval (CI) 0.01-0.05]. The parametric models of serum phosphate from the RCT comparing FCM with SFO provided an estimated OR of 1.17 for the incidence of hypophosphatemia with FCM versus SFO. Combining the two estimates in the MAIC showed that the odds of experiencing hypophosphatemia would be 52.5 (95% CI 27.7-99.4) times higher with FCM than FDI in patients with IDA associated with heavy menstrual bleeding in Japan. CONCLUSIONS: Direct comparison of patient-level data and a MAIC from two RCTs in Japanese patients with heavy menstrual bleeding indicated that hypophosphatemia is less frequent in patients treated with FDI than those with FCM or SFO. Results are in agreement with RCTs comparing FDI and FCM in patients with various etiologies conducted in the USA and Europe.

Airway Injury Caused by Aspiration of Iron Sulfate Pills: A Series of 11 Cases.

It is not widely recognized that iron (ferrous sulfate) pill aspiration causes airway damage. Clinical diagnosis is challenging because patients are often unaware that they have aspirated a pill. The literature on this entity consists mainly of case reports. The aim of this study is to describe the clinical and pathologic features of iron pill aspiration in a series of 11 patients. A retrospective review of our pathology archives was performed to identify cases of iron pill aspiration (2013-2023). All available histologic and cytologic material was rereviewed. Clinical information was collected from the electronic medical record, and imaging studies were rereviewed. Eighteen endobronchial biopsies were identified from 11 patients (7 women and 4 men; mean age, 70 years; range, 44-82 years). Eight patients had corresponding cytology (20 specimens). Medication history was available in 9 of 11 patients, all of whom were taking iron sulfate pills. Two patients reported possible aspiration episodes; 4 had risk factors for aspiration. The diagnosis of iron pill aspiration was suspected prior to biopsy in only 1 case. Histologically, iron pill particles were yellow, golden brown, or gray, were elongated and crystal or fiber like, and stained strongly with an iron stain. Common histologic findings included mucosal ulceration, acute and/or chronic inflammation, fibrosis, and squamous metaplasia. Iron pill particles were also identified in 11 cytology specimens from 6 patients. On Papanicolaou staining, iron pill particles were yellow to golden, fiber like, refractile, and crystalline. Reactive epithelial cells, squamous metaplasia, and acute inflammation were common. The combination of iron pill intake and discolored mucosa on bronchoscopy is a potential clue to the diagnosis of iron pill aspiration. Pathologists should familiarize themselves with the appearance of iron pill particles in endobronchial biopsies and cytology specimens from the respiratory tract as this diagnosis is seldom suspected on clinical grounds, and most patients lack a history of aspiration.

[Consideration of the Characteristics of Oral Iron Preparations from the Viewpoint of the Mechanism of Nausea and Vomiting].

The nausea and vomiting that occur as a result of oral iron administration for the treatment of iron-deficiency anemia (IDA) can cause significant physical and emotional stress in patients. Because iron is absorbed from the intestine as ferrous iron, the most widely used treatment for IDA is oral ferrous agents. However, ferrous forms are more toxic than ferric forms because ferrous forms readily generate free radicals. A randomized, double-blind, active-controlled, multicenter non-inferiority study conducted in Japan showed that ferric citrate hydrate (FC) was just as effective as sodium ferrous citrate (SF) in the treatment of IDA, with a lower incidence of adverse reactions such as nausea and vomiting compared with SF. Animal studies have shown that chemotherapy-induced nausea and vomiting (CINV) involves the release of 5-hydroxytryptamine from enterochromaffin cells by free radicals, and that some chemotherapeutic agents cause hyperplasia of these cells. Enterochromaffin cells also contain substance P, which is known to be also closely related to CINV. We found that administration of SF to rats causes hyperplasia of enterochromaffin cells in the small intestine, whereas FC has no effect on enterochromaffin cells. Oral iron agents may induce nausea and vomiting via the effect of ferrous iron on reactive oxygen species production in the intestine and subsequent enterochromaffin cell hyperplasia. Further research to elucidate the detailed mechanism of enterochromaffin cell hyperplasia induced by ferrous iron preparations is needed to develop a treatment for iron deficiency anemia that causes less gastrointestinal damage.