Iron deficiency anaemia and Helicobacter pylori infection

Iron deficiency anaemia (IDA) is the most common form of anaemia world-wide. IDA is the simple result of an imbalance between iron loss and absorption. Gastric function with hydrochloric and ascorbic acid is essential for iron absorption. Some strains of Helicobacter pylori are able to acquire iron, competing with the host. A large percentage of patients with atrophic body gastritis (ABG) develop IDA and 61% of them are H. pylori positive. Recent evidence suggests that H. pylori infection could cause IDA in the absence of peptic ulcer or other upper gastrointestinal (GI) tract bleeding lesions. Gastritis extending to the corpus and a high bacterial load are features of these patients. About 70% of IDA patients with ABG or H. pylori gastritis are premenopausal women. Both ABG and H. pylori gastritis should be considered when evaluating the GI tract of patients with iron deficiency anaemia.     

儿童幽门螺杆菌感染与缺铁性贫血相关性探讨

目的探讨儿童幽门螺杆菌感染与缺铁性贫血（IDA）的相关性。方法以因慢性腹痛而行胃检查及Hp检测的69例患儿为观察对象,根据检查结果分为Hp阳性慢性胃炎组、Hp阴性慢性胃炎组及Hp阳性胃部镜下无损害组3组,所有病例均检测血红蛋白（Hb）、平均红细胞体积（MCV）、血清铁（SI）、血清铁蛋白（SF）、总铁结合力（TIBC）等IDA指标。比较三组之间的IDA指标和IDA伴发率。结果Hp阴性慢性胃炎组的IDA指标分别与Hp阳性慢性胃炎组、Hp阳性胃部镜下无损害组比较,差异均有统计学意义（P〈0.01,P〈0.05）,而Hp阳性慢性胃炎组的IDA指标与Hp阳性胃部镜下无损害组之间比较,则差异无统计学意义（P〉0.05）。Hp阴性慢性胃炎组的IDA伴发率均低于Hp阳性慢性胃炎组和Hp阳性胃部镜下无损害组（P〈0.05）,Hp阳性慢性胃炎组与Hp阳性胃部镜下无损害组之间的IDA伴发率比较差异无统计学意义（P〉0.05）。结论儿童幽门螺杆菌感染与缺铁性贫血两者之间的相关性有统计学意义,且较慢性胃炎与缺铁性贫血的关系更为密切。     

Benefit of concomitant gastrointestinal and gynaecological evaluation in premenopausal women with iron deficiency anaemia

Background  Iron-deficiency anaemia (IDA) is common in premenopausal women and menorrhagia is often considered responsible.
Aim  To evaluate prospectively the occurrence of bleeding and iron malabsorption related gastrointestinal (GI) diseases likely responsible of IDA in premenopausal women regardless of their menstrual flow.
Methods  One hundred and eighty-seven premenopausal women [median age 39 (20–56) years] irrespective of their menstrual flow underwent gastroscopy with gastric and duodenal biopsies and faecal occult blood test (FOBT). Patients over 50 years, positive 1st degree family history for colonic cancer and/or positive FOBT underwent colonoscopy too.
Results  Menorrhagia was present in 67.4% of premenopausal women. A possible GI cause of IDA was found in 129/187 patients; in 65.2% the cause of IDA was possibly related to iron malabsorption diseases. GI bleeding as a cause of IDA was found in seven patients. An exclusive GI cause of IDA was found in 26.7% of premenopausal women, whereas a possible GI cause was observed in 34.2% of menorrhagic premenopausal women. The main risk factor for the presence of likely GI causes was the presence of upper GI symptoms (OR 5.2: 95% CI = 1.6–16.4).
Conclusions  Most premenopausal women had a possible upper GI cause of IDA because of diseases related to iron malabsorption. Menorrhagia and a GI cause coexist in one-third of women with iron-deficiency anaemia.     

Abnormalities in the upper gastrointestinal tract in inflammatory bowel disease

The predominant histopathologic feature of inflammatory bowel disease is the infiltration of acute and chronic inflammatory cells, including polymorphonuclear neutrophils, macrophages and lymphocytes, in the affected intestine. Helicobacter pylori is recognized as the most common cause of upper gastrointestinal lesions, and Helicobacter pylori-associated gastritis is characterized by increased numbers of acute and chronic inflammatory cells. The pathogenesis of inflammatory bowel disease or Helicobacter pylori-associated gastritis involves immunological abnormalities, including the deficient or excessive expression of cytokines. The chronic inflammatory process in patients with Crohn’s disease may affect any part of the gastrointestinal tract, whereas ulcerative colitis affects mainly the colon and rectum. Here, we discuss abnormalities in the upper gastrointestinal tract in inflammatory bowel disease. Although the prevalence rate of Helicobacter pylori infection is low in Crohn’s disease, these patients often have abnormalities in the upper gastrointestinal tract. Received and accepted 1 August 2006     

Effect of iron deficiency anaemia and its treatment on single dose phenytoin bioavailability

Summary Iron deficiency is a common nutritional deficiency, which leads to structural functional and enzymatic changes in the body that may affect the pharmacokinetics of drugs.The present study in 7 normal volunteers and 8 adult male patients with irondeficiency anaemia (IDA) was done to investigate the effect of iron deficiency and its treatment with total dose iron (TDI) on the bioavailability of a single dose of phenytoin. Phenytoin bioavailability was investigated before and 3 and 28 days after TDI.The bioavailability parameters C_max, t_max, AUC and 2 h phenytoin concentrations were not significantly different in anaemic patients as compared to normal volunteers before or after treatment, except for an increase in t_max 28 days after TDI treatment.     

Involvement of the corporal mucosa and related changes in gastric acid secretion characterize patients with iron deficiency anaemia associated with Helicobacter pylori infection

BACKGROUND: Recent studies have reported an association between iron deficiency anaemia and Helicobacter pylori. Helicobacter pylori could cause iron deficiency anaemia by altering iron absorption. We observed that most patients with Helicobacter pylori infection and iron deficiency anaemia present a chronic superficial pangastritis. AIM: To investigate whether Helicobacter pylori-positive patients with iron deficiency anaemia have peculiar histological and functional features when compared with non-anaemic Helicobacter pylori-positive subjects. PATIENTS: Fifty-one patients with iron deficiency anaemia, in whom chronic superficial Helicobacter pylori gastritis was the only gastrointestinal finding, and 103 non-anaemic Helicobacter pylori-positive controls were included in the study. Thirty-seven patients were randomly matched with 37 controls of the same sex and age. METHODS: Gastroscopy, with antral (n=3) and body (n=3) biopsies, was performed. Gastrin and pepsinogen I levels and antiparietal cell antibodies were evaluated. Intragastric pH was also measured. RESULTS: Gastritis involved the corporal mucosa in 90% of patients compared to 42.7% of controls (P < 0.0001). The mean inflammatory score in the gastric body was significantly higher among patients than in controls (2.2 vs. 0.6; P=0.012). Gastrin was significantly higher in patients than in controls (mean 60.2 vs. 29 pg/mL; P=0.0069). Intragastric pH was higher in patients than in controls (median 5.7 vs. 2; P=0.0026). CONCLUSIONS: These data suggest that patients with iron deficiency anaemia and Helicobacter pylori infection have a peculiar pattern of gastritis with corporal involvement and related changes in intragastric pH.     

幽门螺杆菌感染与缺铁性贫血的关系

目的探讨幽门螺杆菌（Hp）感染与缺铁性贫J缸（IDA）的关系,以及Hp相关IDA的治疗。方法分别统计40例IDA伴慢性胃炎与42例非IDA慢性胃炎两组Hp感染率。将36例Hp感染相关IDA随机分成两组,分别应用根除细菌加口服铁剂与单用铁剂方案治疗,检测治疗前后血液学指标,观察疗效。结果IDA伴慢性胃炎者Hp感染率为90％高于非IDA慢性胃炎者（70％）,两者差异有统计学意义;Hp感染相关IDA患者接受根除细菌加铁剂治疗前后其Hb、血清铁、铁蛋白均显著增高,而单用铁剂组治疗前后血液学指标无显著变化。结论Hp感染与IDA可能有一定相关性,当IDA患者铁剂治疗效果不显著时宜考虑是否存在Hp相关IDA;根除Hp感染后对IDA有一定治疗作用。     

Gastric corpus IL-8 concentration and neutrophil infiltration in duodenal ulcer patients

Background: The purpose of the present study was to examine the association between interleukin-8 (IL-8) in the gastric body due to Helicobacter pylori infection and histological gastritis, as well as elucidating the effect of acid secretion inhibitors on H. pylori associated body gastritis in duodenal ulcer patients. Methods: Twenty H. pylori-negative patients, 20 H. pylori-positive patients with chronic gastritis without peptic ulceration, and 20 H. pylori-positive duodenal ulcer patients (DU) were studied. Four biopsy samples were taken, each from the greater curvature of the antrum and body of the stomach. Biopsies were histologically investigated by ELISA to determine the density of H. pylori, the degree of neutrophil infiltration and the IL-8 concentration in the mucosa. Results: In the gastric mucosa of H. pylori-negative subjects, no IL-8 and hardly any neutrophil infiltration were observed. In contrast, enhanced IL-8 production and increased neutrophil infiltration were present in those infected with H. pylori. In H. pylori-positive patients, a significant correlation was observed between the IL-8 concentration and the degree of neutrophil infiltration, but no correlation was found in the body mucosa of those with DU. Twelve of 20 DU patients demonstrated hardly any neutrophil infiltration, despite the increased mucosal IL-8 content in the body. The administration of omeprazole in DU patients markedly increased mucosal neutrophil infiltration even though it did not cause any significant change in the H. pylori density and IL-8 concentration in the body. Although the effect of omeprazole was transient, a significant increase in neutrophil infiltration continued in comparison with the status before omeprazole administration in those subsequently undergoing maintenance treatment with H₂-blockers. Conclusion: In H. pylori-positive chronic gastritis, IL-8 concentration is enhanced in the mucosa of the body, and is associated with increased neutrophil infiltration. However, in DU patients, despite increases in body IL-8 concentration, neutrophil infiltration is reduced and the gastritis may be localized in the antrum.     

单个网织红细胞血红蛋白浓度在缺铁性贫血诊断中的应用价值

目的 用单个网织红细胞血红蛋白浓度(CHr)与铁蛋白(SF),转铁蛋白受体(sTfR)及红细胞参数作联合试验和对照,研究CHr在缺铁性贫血(IDA)诊断中的应用价值。方法 对我院110例内科门诊病人进行CHr和其它缺铁参数的联合试验和对照,经临床根据国内IDA标准确诊的IDA病人21例,非IDA贫血病人15例,非贫血病人74例,计算CHr诊断IDA的敏感度和特异性及与其它参数的符合度,以评价CHr在IDA诊断中的应用价值。结果 CHr诊断IDA的敏感度为95.0%,特异性为80.0%,与SF的符合就率为90.0%,转铁蛋白受体(sTfR)的符合率为89.6%, Hb的符合率为70.2%, IDA病人CHr较非IDA人群CHr有明显降低(P<0.01)。结论 CHr可作为缺铁性贫血的诊断指标,尤其适用于IDA的早期诊断。     

Comparison Study of Oral Iron Preparations Using a Human Intestinal Model

Iron deficiency and related iron deficiency anaemia (IDA) are the most prevalent nutritional disorders worldwide. The standard treatment involves supplementation with solid or liquid iron supplement preparations, usually based on a ferrous salt such as ferrous sulphate, ferrous fumarate, or ferrous gluconate. In the present study, we compared iron uptake and absorption from various solid and liquid iron supplement preparations currently available in the United Kingdom using the well-characterised human epithelial adenocarcinoma cell line Caco-2. Intracellular ferritin protein formation by the Caco-2 cell was considered an indicator of cellular iron uptake and absorption. We investigated the effects of formulation ingredients at a defined pH on iron uptake and absorption, and designed a novel two-stage dissolution-absorption protocol that mimicked physiological conditions. Our experiments revealed wide variations in the rate of dissolution between the various solid iron preparations. Conventional-release ferrous iron tablets dissolved rapidly (48 ± 4 mins to 64 ± 4 mins), whereas modified-released tablets and capsules took significantly longer to undergo complete dissolution (274 ± 8 to 256 ± 8 mins). Among the solid iron preparations, ferrous sulphate conventional-release tablets demonstrated the highest iron absorption, whereas modified-release ferrous preparations demonstrated uniformly low iron absorption, as compared to the control (P < 0.05). Taken together, our results demonstrate that there are wide-ranging variations in dissolution times and iron uptake from oral iron preparations, with the physical characteristics of the preparation as well as the form of iron playing a key role.     

Anti-Helicobacter pylori effect of costunolide isolated from the stem bark ofMagnolia sieboldii

Helicobacter pylori (H. pylori) infection is now established as the major pathogenic factor in chronic gastritis and peptic ulcer disease. In addition, there is accumulating evidence thatH. pylori plays an important role in the process of gastric carcinogenesis. On the other hand, oriental traditional medicines have been used for stomach disease for thousands of years. In the present study, methanol extract from the stem bark ofMagnolia sieboldii (M. sieboldii) and its components were investigated on their inhibitory effects against urease activity and growth ofH. pylori in vitro. The methanol extract ofM. sieboldii significantly inhibited the growth ofH. pylori ATCC 43504 at 5 mg/ml. From the further fractionation, the chloroform fraction inhibited the bacterial growth dose-dependently. Among four fractions separated from the chloroform fraction by silica gel column chromatography, MS-C-2 was the most potent. Costunolide was isolated from the MS-C-2 subfraction by preparative TLC and recrystallization using n-hexane. Anti-H. pylori effect of costunolide was investigated using one commercial strain (H. pylori ATCC 43504) and three clinical strains (H. pylori 4, 43, 82548). Costunolide exhibited potent anti-H. pylori activity, and the MIC was around 100–200 μg/ml. However, costunolide had no inhibitory effect ofH. pylori urease activity at the concentration used for the growth inhibition assay. From these results, we conclude that costunolide inhibits the growth ofH. pylori by the independent manner ofH. pylori urease inhibition.     

Helicobacter pylori, parietal cell antibodies and autoimmune gastropathy in type 1 diabetes mellitus

BACKGROUND: Fifteen to 20% of type 1 diabetic patients exhibit parietal cell antibodies (PCA), which are associated with autoimmune gastritis, hypochlorhydria, iron deficiency and pernicious anaemia. AIM: To examine whether Helicobacter pylori infection could explain the high prevalence of PCA and autoimmune gastropathy in diabetes. If so, H. pylori eradication could prevent autoimmune gastritis. METHODS: In 229 type 1 diabetics (M/F: 135/94; age: 41 +/- 12 years) PCA were measured. H. pylori infection was assessed by serology, urea breath test in all and by histology (updated Sydney system) in 88 subjects. Pentagastrin tests were performed in 42 patients. RESULTS: Sixty-nine patients were PCA-positive. H. pylori infection was present in 72 patients and was negatively associated with HLA-DQA1*0103-B1*0603 (OR=0.12, P=0.015) and positively with DQA1*0501-B1*0201 (OR=1.9, P=0.032). PCA-positivity was linked to HLA-DQA1*0501-B1*0301 (OR=3.9, P=0.017). A link between H. pylori and PCA was observed when PCA-positivity was defined as a titre > or = 1/20 (OR=2.0, P=0.03), but not if > or =1/40 was the cut-off point. PCA-positivity, but not H. pylori infection, was associated with iron deficiency anaemia (OR=2.7, P=0.008), pernicious anaemia (OR= 33.5, P < 0.0001), hypochlorhydria (OR=12.1, P=0.0008) and autoimmune gastritis (OR=12.5, P < 0.0001). CONCLUSIONS: The HLA-bound susceptibility of H. pylori and PCA differed. PCA-positivity but not ongoing H. pylori infection is associated with autoimmune gastritis. Low titres of PCA might reflect H. pylori infection rather than autoimmune gastropathy.     

Assessment and significance of Helicobacter pylori infection

Although Helicobacter pylori gastritis, that is, H. pylori infection and its complications, is currently the focus of tremendous research activity, there is no gold standard test for its detection. Current methods of assessment of H. pylori infection are reviewed in this paper, and the diseases associated with the bacterium are discussed. Histological tests can indicate the presence of infection with H. pylori. Culture tests, however, are more specific but rely on the presence of viable bacteria, and the polymerase chain reaction (PCR) can detect DNA from H. pylori. Indirect methods of detecting infection include urease tests, but these recognize only active bacteria. Serological tests are usually satisfactory screening methods but are not suitable for assessing treatment outcome. There are now many reports that associate diseases other than peptic ulcer disease with the presence of H. pylori infection. In 1994, the International Agency for Research on Cancer, sponsored by the World Health Organization, classified the bacterium as a group I carcinogen. Results of studies on patients with functional dyspepsia indicate that eradication of H. pylori gives a range of levels of symptom relief, from no relief to significant relief, with a geometric mean value indicating a positive effect on a sub-group of this category of patients. Other groups of patients with symptoms similar to functional dyspepsia and a significant risk for negative investigation are those with endoscopy negative reflux, mucosa-associated lymphoid tissue (MALT) lymphoma or mild non-steroidal anti-inflammatory drug (NSAID) lesions. Both MALT lymphoma and NSAID lesions are partly linked to H. pylori infection, while the possible correlation between reflux disease and H. pylori infection is controversial. In conclusion, H. pylori gastritis seems to be associated with a number of complications, some of which are serious. There are no reliable data showing any positive aspects of the infection. Eradication of H. pylori infection should therefore, in most cases, be regarded as an appropriate therapeutic strategy.     

Prevalence of coeliac disease and relations to Helicobacter pylori infection and duodenitis in a Swedish adult population sample: a histomorphological and serological survey

Aim: The aim of this study was to determine the prevalence of coeliac disease and its relation to duodenitis, H. pylori infection and gastritis in a sample of the adult general population. Methods: A Swedish population sample of 482 subjects (aged 35 to 85 years) were examined with gastro-duodenoscopy with multiple biopsies taken. Circulating antibodies to endomycium, gliadin, and H. pylori were also determined. Results: Based on histomorphological findings, coeliac disease was evident in 9 of 482 subjects giving a prevalence of 1.9 [1.0-4.0, 95% confidence interval] percent. The prevalence of gastritis with or without H. pylori infection did not differ between subjects with and without coeliac disease. Considering subjects without coeliac disease, there was no difference in the serum levels of gliadin antibodies between those with and without duodenitis. However, subjects with positive H. pylori status had significantly higher levels of gliadin antibodies than those with negative H. pylori status. Conclusions: This study confirms that there is a relatively high prevalence of undiagnosed coeliac disease in Swedish adults. There was no association between coeliac disease and H. pylori infection or gastritis, although serum gliadin antibody levels were slightly increased in subjects with positive H. pylori status.     

伴幽门螺杆菌感染的缺铁性贫血40例治疗观察

目的研究针对抗幽门螺杆菌（Hp）治疗对伴有Hp感染的缺铁性贫血（IDA）治疗的影响。方法选择40例Hp阳性的缺铁性贫血患者,根据治疗方法不同分组为A、B两组,A组24例,给予抗Hp加铁剂治疗;B组16例,给予单纯铁剂治疗,观察两组治疗前后血红蛋白、血清铁蛋白的变化。结果A组患者治疗后血红蛋白、血清铁蛋白较B组患者恢复快（P〈0．05）。结论Hp感染是缺铁性贫血的病因之一,给予抗Hp治疗是Hp（＋）缺铁性贫血治疗必需的措施。     

Omeprazole, bismuth and clarithromycin in the sequential treatment of Helicobacter pylori infection

Aims: To assess the therapeutic potential of clarithromycin, a new macrolide with high anti-Helicobacter pylori activity, given with bismuth salts and omeprazole in different regimens aimed at simplifying the treatment of H. piylon-related gastritis. Methods: Eighty-eight patients with proven H. pylori infection and gastritis were treated with one of the following four regimens: omeprazole 40 mg/day for one week (group A. n = 14); omeprazole 40 mg/day for one week followed by clarithromycin 1 g/day for 2 weeks (group B, n = 26); omeprazole 40 mg/day for one week followed by tripotassium dicitrato bismuthate 480 mg/day and clarithromycin 1 g/day, both for two weeks (group C, n = 26); and tripotassium dicitrato bismuthate 480 mg/day and clarithromycin 1 g/day for two weeks (group D, n = 22). Presence of H. pylori, histology and electron microscopy were assessed at entry and four weeks after the end of each treatment. Results: Omeprazole alone had no effect on H. pylori status. The highest eradication rate was obtained in group C patients (81%), a proportion significantly greater than that observed in group B (50%, P < 0.03) or group D patients (55%, P < 0.05). Conclusion: Sequential treatment may be a useful option in the treatment of H. pylori-related gastritis.     

Newly diagnosed iron deficiency anemia and subsequent autoimmune disease: a matched cohort study in Taiwan

Abstract

Objective: To explore whether newly diagnosed iron deficiency anemia (IDA) is associated with subsequent systemic autoimmune disease onset.

Methods: The study identified 22,440 patients who received a diagnosis of IDA between 2000 and 2012 from a random sample of 1 million people from Taiwan’s National Health Insurance Research Database. The patients with IDA were randomly matched with 89,528 patients with no IDA by age, gender, and index year. We followed the 2 groups until systemic autoimmune disease onset. Cox proportional hazards analysis was used to determine autoimmune disease risk by age, gender, and comorbidities, in terms of hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: Adjusted HR (95% CI) of autoimmune disease in the IDA group was 2.37 (1.92–2.92) compared with the non-IDA group. The subgroup analysis indicated that a patient with IDA had a significantly greater risk of autoimmune disease if they were female or had the comorbidities of hypertension, hyperlipidemia, cancer, allergic rhinitis, urticaria, chronic obstructive pulmonary disease, or chronic liver disease. The autoimmune disease was significantly more likely to occur within 2?years after a new diagnosis of IDA.

Conclusions: IDA significantly increases autoimmune disease risk, particularly in female patients and patients with certain comorbidities. Clinicians should conduct further clinical evaluations and laboratory tests of autoimmune disease in patients with IDA.     

蔗糖铁注射液治疗缺铁性贫血临床观察

目的：探讨静脉用蔗糖铁治疗缺铁性贫血（IDA）的有效性和安全性。方法：选择60例IDA患者。随机分为静脉组和口服药物组,观察两种方法对纠正缺铁、改善贫血的效果和不良反应。结果：治疗后两组患者血红蛋白（Hb）、铁蛋白（Fer）均较治疗前明显升高。静脉组Hb、Fer上升幅度明显高于口服组,差异显著。静脉组无明显不良反应,口服组有12例（20．00％）发生胃肠道反应。结论：静脉用蔗糖铁可作为IDA患者有效治疗方法,疗效优于口服铁剂,且不良反应发生率低。     

Medicinal plants in the treatment of Helicobacter pylori infections

Abstract

Context: Helicobacter pylori is a small, spiral, Gram-negative bacillus that plays a role in the pathogenesis of a number of diseases ranging from asymptomatic gastritis to gastric cancer. Schedule compliance, antibiotic drug resistance, and side-effects of triple or quadruple therapy have led to research for novel candidates from plants.

Objective: The purpose of this paper is to review the most potent medicinal plants of recently published literature with anti-H. pylori activity. For centuries, herbals have been used by traditional healers around the world to treat various gastrointestinal tract disorders such as dyspepsia, gastritis, and peptic ulcer disease. The mechanism of action by which these botanicals exert their therapeutic properties has not been completely and clearly elucidated. Anti-H. pylori properties may be one of the possible mechanisms by which gastroprotective herbs treat gastrointestinal tract disorders.

Materials and methods: Electronic databases such as PubMed, Google scholar, EBSCO, and local databases were explored for medicinal plants with anti-H. pylori properties between 1984 and 2013 using key words “medicinal plants” and “Helicobacter pylori” or “anti-Helicobacter pylori”.

Results: A total of 43 medicinal plant species belonging to 27 families including Amaryllidaceae, Anacardiaceae, Apiaceae, Apocynaceae, Asclepiadoideae, Asteraceae, Bignoniaceae, Clusiaceae, Chancapiedra, Combretaceae, Cyperaceae, Euphorbiaceae, Fabaceae, Geraniaceae, Lamiaceae, Lauraceae, Lythraceae, Menispermaceae, Myristicaceae, Myrtaceae, Oleaceae, Papaveraceae, Plumbaginaceae, Poaceae, Ranunculaceae, Rosaceae, and Theaceae were studied as herbs with potent anti-H. pylori effects.

Conclusion: Traditional folk medicinal use of some of these plants to treat gastric infections is substantiated by the antibacterial activity of their extracts against H. pylori.     

Preventing complications by persistence with iron replacement therapy: a comprehensive literature review

Objective: Iron deficiency and particularly iron deficiency anemia (IDA) can lead to negative health consequences. This review describes the importance of adherence and persistence (adhering to treatment for the recommended duration) with iron replacement therapy in the prevention of complications, particularly regarding its recommended dosing schedule.

Methods: Comprehensive literature searches were performed of Medline and the Cochrane library from 2000 to 2018. Keywords included iron deficiency or IDA, compliance or adherence, persistence, health beliefs, risk factor, complications, dosing cycles, oral iron replacement therapy and recommendations for duration, ferrous compounds, iron supplementation, dietary iron, and delayed-action/slow-release preparations.

Results: Identified articles focused on IDA as a risk factor (particularly for worsened comorbidities or surgical outcomes), guidelines, adherence and persistence, and differences between iron formulations. Current guidelines and expert opinion continue to support oral iron supplementation as first-line therapy. While it is recommended to take iron therapy for 2 months to normalize hemoglobin, then 2–3 months to build up iron stores, many patients face difficulties in adhering to and persisting with the full iron treatment regimen. Patient education and understanding, social support, simple dosing, perceived efficacy including reduced symptoms and tolerability were factors noted to promote medication adherence and persistence. Adherence to iron therapies appears to be facilitated by using ferrous sulfate due to its optimal absorption, and particularly extended-release forms due to their improved tolerability for iron deficiency.

Conclusions: Proper adherence and persistence with iron supplementation may prevent or reduce the risk of complications of iron deficiency and IDA.