Prevalence and risk factors for iron-deficiency anemia in very-low-birth-weight preterm infants at 1 year of corrected age

Effect of Iron Polymaltose Complex Prophylaxis on Frequency of Iron Deficiency and Iron Deficiency Anemia

OBJECTIVES

To evaluate the effectiveness of national iron prophylaxis policy in 9-12 mo-old infants in Turkey.

METHODS

This study was planned as a cross-sectional study, and it included healthy infants aged 9 to 12 mo who presented to the pediatric outpatient clinic for routine check-ups. Parents were interviewed to identify risk factors for iron deficiency (ID) and gather information on Fe+3 - iron polymaltose complex (IPC) prophylaxis usage. Blood samples were collected for hemogram and ferritin analysis. Multiple logistic regression analyses were conducted to determine risk factors for ID and iron deficiency anemia (IDA).

RESULTS

The study included 317 infants. In the non-prophylaxis group, the frequency of IDA was 31.1%, compared to 13.4% in the regular prophylaxis group. Iron deficiency was detected in 25% of individuals receiving regular prophylaxis and 13.1% of those without prophylaxis. The risk factors for IDA were insufficient iron diets (OR 2.45, 95% CI: 1.35-4.45) and not receiving Fe+3 - IPC prophylaxis (OR 2.57, 95% CI: 1.24-5.31). The relationship between Fe+3 - IPC prophylaxis and ID did not reach statistical significance (p = 0.253).

CONCLUSIONS

Fe+3 - IPC prophylaxis is associated with a lower risk of iron deficiency anemia, but not iron deficiency.

The effect of iron supplementation in preterm infants at different gestational ages

BACKGROUND

Iron deficiency (ID) is the most prevalent nutritional deficiency disease in preterm infants, significantly affecting their growth and development. For preterm infants to flourish physically and neurologically, timely iron supplementation is essential. The main goals of this study were to determine whether the present iron supplementation regimen results in iron overload in late preterm infants and whether it can meet the growth requirements of early preterm infants for catch-up.

METHODS

We conducted a prospective follow-up study on preterm infants at the Department of Child Health, West China Second University Hospital, Sichuan University, from January 1, 2020, to August 31, 2020. In this study, 177 preterm infants were divided into two groups based on gestational age-early preterm infants (gestational age < 34 weeks) and late preterm infants (gestational age ≥ 34 weeks and < 37 weeks)-to compare the incidence of iron deficiency, iron status, and physical growth of preterm infants receiving iron supplements (2-4 mg/kg/d).

RESULTS

Iron supplementation considerably reduced the incidence of iron deficiency in preterm infants. The prevalence of iron deficiency in early preterm infants and late preterm infants was 11.3% and 5.1%, respectively, at the corrected gestational age of 3 months; at the corrected gestational age of 6 months, the prevalence was 5.3% and 6.3%, respectively. No preterm infants with iron deficiency were detected in either group at the corrected gestational age of 12 months. Ferritin was substantially lower in early preterm infants (36.87 ± 31.57 ng/ml) than in late preterm infants (65.78 ± 75.76 ng/ml) at the corrected gestational age of 3 months (p < 0.05). A multifactorial regression analysis of factors influencing iron metabolism levels in preterm infants revealed a positive relationship between log10hepcidin, birth weight, and ferritin, with higher birth weights resulting in higher ferritin levels.

CONCLUSIONS

Postnatal iron supplementation at 2-4 mg/kg/d in preterm infants significantly decreases the incidence of ID. There were substantial differences in iron levels across preterm infants of varying gestational ages. A tailored iron supplementation plan based on growth, birth weight, and gestational age may be a more suitable route for iron supplementation. Although the current study found that the postnatal iron status of early preterm infants differed from that of late preterm infants, the actual mechanism of action remains unknown, and large-sample, multicenter clinical studies are required to investigate this further.

Non Breast-Milk-Fed Very Preterm Infants Are at Increased Risk of Iron Deficiency at 4-6-Months Corrected Age: A Retrospective Population-Based Cohort Study

Iron supplementation is routinely recommended for breast-milk-fed preterm infants. However, the Canadian Pediatric Society recommends no additional iron supplementation for preterm infants fed primarily with iron-rich formula. Other pediatric societies don't provide specific guidance on supplemental iron for formula-fed preterm infants. This study investigated how feeding type influences iron status of very preterm infants at 4-6-months corrected age (CA). A retrospective cohort study was conducted using a population-based database on all very preterm infants (<31 weeks gestational age) born in Nova Scotia, Canada from 2005-2018. Information about feeding type, iron intake from formula, supplemental iron therapy and iron status at 4-6-months CA was extracted. Iron deficiency (ID) was defined as serum ferritin <20 and <12 µg/L at 4-and 6-months CA, respectively. Of 392 infants, 107 were "breast-milk-fed" (exclusively or partially) and 285 were "not breast-milk-fed" (exclusively fed with iron-rich formula) at 4-6-months CA. Total daily iron intake was higher in the non-breast-milk-fed group (2.6 mg/kg/day versus 2.0 mg/kg/day). Despite this, 36.8% of non-breast-milk-fed infants developed ID versus 20.6% of breast-milk-fed infants. ID is significantly more prevalent in non-breast-milk-fed infants than breast-milk-fed infants despite higher iron intake. This suggests the need to revisit recommendations for iron supplementation in non-breast-milk-fed preterm infants.

Accuracy of reticulocyte hemoglobin for diagnosing iron deficiency in former very preterm infants: a population-based cohort study

Background

Serum ferritin (SF) is commonly used to diagnose iron deficiency (ID) but has limitations. Reticulocyte hemoglobin (Ret-He) is being increasingly used for ID diagnosis. This study aimed to assess accuracy of Ret-He for ID diagnosis in former very preterm infants (VPI) at 4-6 months corrected age (CA).

Methods

A retrospective population-based cohort study was conducted on all live VPI born between 23 and 30 weeks of gestational age (GA) in Nova Scotia from 2012 to 2018. Infants underwent SF and Ret-He testing at 4-6 months CA. ID was defined using two definitions. The first defined ID as SF < 20 mcg/L at both 4- and 6-months CA, and the second as SF < 30 mcg at at both 4- and 6-months CA. The accuracy of Ret-He for identifying ID was assessed using the area under the receiver operating characteristic curve (AUC).

Results

ID was present in 39.7% (62) of 156 infants in the first definition and 59.6% (93) in the second at 4-6 months CA. The AUC of Ret-He for ID diagnosis was 0.64 (p = 0.002) in the first definition and 0.59 (p = 0.04) in the second. The optimal cut-off was 29.4pg in the first and 29.7 in the second definition. The sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) at the 29.4 pg cut-off were 50.0%, 78.7%, 60.8%, and 70.5% for definition 1 and 44.1%, 74.6%, 71.9%, and 47.5% at the 29.7pg cut-off for definition 2.

Conclusion

Ret-He had low diagnostic accuracy for ID diagnosis in former VPI. Caution is advised when using Ret-He alone for ID diagnosis. Further research is needed to establish optimal approaches for identifying ID in VPI.

Rapid increase in the body mass index of very preterm infants is a risk factor for iron deficiency during infancy

Iron deficiency (ID) in very preterm infants born at 28-32 weeks of gestational age (GA) can lower mental and motor test scores. This study aimed to determine whether the rapid growth of very preterm infants might be associated with ID. Among 134 very preterm born between January 2014 and December 2020 at Jeonbuk National University Hospital and discharged home, 93 were included in this study. Rapid BMI increase (RBI) was defined as a z-score difference of > 1 standard deviation between birth and 8 months. ID occurred in 23 of 93 (24.7%) infants at 8 months of corrected age (CA). ID was more common in the RBI group (50%) than in the non-RBI group (18.7%). In the multivariate logistic regression corrected for GA, infants small for gestational age (SGA) (odds ratio [OR] 6.06, 95% confidence interval [CI] 1.34-30.21) and RBI by z-score (OR 4.26, 95% CI 1.28-14.65) were identified as independent risk factors for ID at 8 months of CA. Conclusively, both SGA and RBI in the early life of very preterm were risk factors for ID at 8 months of CA.

Postdischarge Iron Status in Very Preterm Infants Receiving Prophylactic Iron Supplementation after Birth

OBJECTIVE

To determine postdischarge iron status and associated factors in very preterm infants.

STUDY DESIGN

A retrospective cohort study was conducted through a provincial database on all very preterm infants born in Nova Scotia between 2005 and 2018. As a standard of care, all infants received prophylactic iron supplements starting at 2-4 weeks of chronological age and were tested for iron deficiency at 4 or 6 months corrected age. Iron deficiency was defined as serum ferritin <20 g/L at 4 months or <12 g/L at 6 months. Multivariate logistic regression analysis identified factors associated with iron deficiency.

RESULTS

Among 411 infants, 132 (32.1%) had iron deficiency and 11 (2.7%) had iron deficiency anemia. The prevalence of iron deficiency decreased over time, from 37.6% in 2005-2011 to 25.8% in 2012-2018. Gestational hypertension in the mother (P = .01) and gestational age <27 weeks (P = .02) were independent risk factors for iron deficiency. In addition, the odds of iron deficiency were lower in the mixed-fed group (ie, with breast milk and formula combined) compared with the exclusive formula-fed group (P = .01).

CONCLUSIONS

Iron deficiency was prevalent in 32% of the very preterm infants despite early iron prophylaxis. These results demonstrate the importance of monitoring iron stores during preterm follow-up. Information about risk factors is important to mitigate iron deficiency in very preterm infants.

Early Childhood Caries and Iron Deficiency Anaemia: A Systematic Review and Meta-Analysis

Identification of the association between Early Childhood Caries (ECC) and Iron Deficiency Anaemia (IDA) will aid paediatricians and paediatric dentists to enhance health promotion measures to reduce the related morbidity in children. This systematic review aims to determine an evidence-based association between ECC and IDA. A systematic search was carried out from MEDLINE via PubMed, EMBASE, LILACS, Cochrane Oral Health Group's Specialized Register, CINAHL via EBSCO, Web of Science, and Scopus up to May 2020. Hand searching and grey literature screening were also conducted. Cross-sectional, case-control, and cohort studies in English language which assessed the association was included. Two reviewers independently assessed the study quality and extracted the outcome data. A total of 1,434 studies were identified. Fourteen studies qualified for qualitative review and 7 of them for a meta-analysis. In comparison with children not affected by ECC, those affected had an increased likelihood of IDA (OR = 6.07 [3.61, 10.21]). The meta-analysis showed no statistical difference when comparing blood parameters (Hb, MCV, and serum ferritin) in children with and without ECC. This systematic review demonstrates an association between ECC and increased odds of IDA rather than it being the cause for IDA. Further longitudinal studies with robust methodology are required to determine an evidence-based association.

Association between Iron Supplementation, Dietary Iron Intake and Risk of Moderate Preterm Birth: A Birth Cohort Study in China

Background:

To evaluate the independent and collective effects of maternal iron supplementation and dietary iron intake upon the risk of moderate preterm birth and its subtypes.

Methods:

In this birth cohort study, 1019 pregnant women with moderate preterm birth and 9160 women with term birth were recruited at Gansu Provincial Maternity and Child Care Hospital from 2010–2012 in China. Unconditional logistic regression models were utilized to evaluate the association between maternal iron supplementation, dietary iron intake, and the risk of moderate preterm birth and its subtypes.

Results:

Compared with non-users, iron supplement users exerted a protective effect upon the overall (OR=0.54, 95%CI=0.40–0.72) and spontaneous moderate preterm birth (OR=0.39, 95%CI=0.33–0.83). Compared with the 25^th quartiles of dietary iron intake, either before or during pregnancy, it exerted a significantly protective effect upon those who had the highest quartiles of dietary iron intake (OR=0.87, 95%CI=0.82–0.95 for the highest quartiles of dietary iron intake before pregnancy OR=0.85, 95%CI=0.79–0.91). Positive association was observed between the additive scale and multiplicative scale for preterm birth, spontaneous preterm rather than medically indicated preterm.

Conclusion:

Iron supplements (60 mg/day) and high-iron intake (>25.86 mg/day before pregnancy, >30.46 mg/day during pregnancy) reduced the risk of moderate preterm birth. Positive correlation is found between the additive scale and multiplicative scale for preterm birth, spontaneous preterm birth.

Spatial variations and determinants of anemia among under-five children in Ethiopia, EDHS 2005-2016

BACKGROUND

Anemia has severe public health significance in sub-Saharan Africa. In Ethiopia, anemia has been increasing in the last two decades, reaching the highest national level in 2016, however, the geospatial distribution and determinants of anemia in children weren't well explored at a national level.

METHODS

We used the Ethiopian Demographic and Health Survey(EDHS) data from 2005-2016. The data consists of samples of households (HHs) obtained through a two-stage stratified sampling procedure. Our analysis included 19,699 children. Descriptive statistics, geospatial analysis, and Generalized Linear Mixed Model (GLMMs) were used.

RESULTS

The overall prevalence of anemia was 51.5%; the spatial distribution of anemia significantly different across clusters in each survey. Children from 6 to 11 months had higher odds of anemia compared to 24-59 months (Adjusted Odds ratio (AOR) = 3.4, 95%Confidence level (CI): 2.99-3.76). Children with the first and second birth order were less likely to be anemic compared to fifth and above (AOR = 0.60, 95%CI: 0.38-0.95, and AOR = 0.83, 95%C: 0.73-0.93) respectively. Mothers' age 15 to 24 years was associated with higher odds of anemia compared to 35 to 49 years (AOR = 1.37, 95%CI: 1.20-1.55). Children from HHs with the poorest and poorer wealth category showed a higher odds of anemia compared to the richest (AOR = 1.67, 95%CI: 1.45-1.93, and AOR = 1.25, 95%CI: 1.08-1.45) respectively. Moreover, children from HHs with one to two under-five children were less likely to be anemic compared to those three and more (AOR = 0.83, 95%CI: 0.76-0.91).

CONCLUSIONS

The geospatial distribution of anemia among children varies in Ethiopia; it was highest in the East, Northeast, and Western regions of the country. Several factors were associated with anemia; therefore, interventions targeting the hotspots areas and specific determinant factors should be implemented by the concerned bodies to reduce the consequences of anemia on the generation.

Compliance to Iron-Folic Acid Supplementation and Its Association with the Number of ANC Visits in Ethiopia: Systematic Review and Meta-Analysis

Background

The World Health Organization recommended that 80% of communities in all countries should receive the standard dose of iron folic acid. But, in Ethiopia, this target was not yet achieved. The compliance of iron folic acid was also variable across each district. Therefore, the aim of this study was to assess women compliance with iron-folic acid supplementation and its association with a number of antenatal care visits in Ethiopia using systematic review and meta-analysis, 2018.

Methods

In the current meta-analysis, the target variables were searched from different electronic database system like PubMed, Google Scholar, Science Direct, and Cochrane Library. To predict the pooled prevalence of compliance with iron-folic acid supplementation in Ethiopia, all original studies were considered. All necessary data were extracted by using a standardized data extraction format. The data were analyzed by using STATA 14 statistical software. Heterogeneity between the studies was assessed by Cochrane Q and I² tests. A random effect model was computed to estimate the pooled compliance with iron-folic acid supplementation.

Results

Twelve full-text studies were included in the meta-analysis. The findings of this meta-analysis revealed that the pooled prevalence of compliance with iron-folic acid supplementation in Ethiopia was 43.63% (CI: 28.00, 59.25%). The women from the city administration had a high rate of compliance as compared with other regions of Ethiopia. The odds of having four or more antenatal care visit were the independent pooled predictor of compliance with iron-folic acid supplementation.

Conclusion

Current compliance with iron-folic supplementation was lower than the World health organization recommendation. Mothers from the city administration who utilized the antenatal care four and above times, had high level compliance with iron-folic acid supplementation. Therefore, we recommended that women should visit the antenatal clinic four times to compliance with the iron folic acid supplementation.

Weight, height, and midupper arm circumference are associated with haemoglobin levels in adolescent girls living in rural India: A cross-sectional study

We aimed to explore the association of physical parameters with haemoglobin (Hb) levels to test the hypothesis that impaired physical development is associated with anaemia. A cross‐sectional survey study recruited adolescent girls (13 to 17 years) living in rural areas of Maharashtra state of India. Data were collected on physical parameters include height, weight, and midupper arm circumference (MUAC). Hb levels were measured using Sahli's haemometer. Linear regression was conducted to test the hypothesis. Data were collected from 1,010 girls on physical parameter and Hb levels. The majority of the adolescent girls were diagnosed with anaemia (87%). The regression analysis adjusted for age gave a significant association of Hb levels with all three variables (MUAC, weight, and height). Hb increased by 0.11 g/dl with an each centimetre of increase in MUAC (95% confidence interval, CI, [0.08, 0.15], P < .001). Each kilogram of increase in the body weight showed an increase in Hb levels (0.02 g dl, 95% CI [0.01, 0.03], P = .001). With an each centimetre of increase in height, Hb increased by 0.01 g dl (95% CI [0.00, 0.02], P = .022). There was a consistent association between three measures of somatic growth and anaemia in the study population. It is likely that life‐course exposures from conception onwards contribute to this, and the public health implications are that preventing anaemia is a challenge that requires a multifaceted interventional approach. Understanding the importance of the timing of these life exposures will help design interventions that can achieve optimal results.

First-year growth of 834 preterm infants in a Chinese population: a single-center study

BACKGROUND

The aim of this study was to follow the growth and hematological indicators of preterm infants during their first year.

METHODS

Neonates below 37 gestational weeks had routine follow-ups up through 1 year from January 2012 to December 2015 at West China 2nd University Hospital, Sichuan University. Weight, length and head circumference (HC) were measured monthly during the first 6 months, followed by monitoring every second month until 12 months. The catch-up growth defined as a gain of Z-score > 0.67 according to previous study. All preterm infants were prescribed iron prophylaxis based on national guideline. The hemoglobin concentration was examined at 6 and 12 months.

RESULTS

Altogether, 132 very-low-birth-weight (VLBW), 504 low-birth-weight (LBW) and 198 normal-birth-weight (NBW) infants were followed. The rates of catch-up growth for weight, length and HC 12 months of corrected age (CA) were 22.6, 29.1 and 14.6%, respectively. SGA and VLBW infants showed higher catch-up growth rates. The overall prevalence of anemia was 6.8% at 6 months and 7.8% at 12 months. The Z-scores for weight-for-length, length and HC were lower in the VLBW and SGA preterm infant groups than in the other preterm groups throughout the first year of life. The incidences of stunting, microcephaly and wasting changed from 5, 1.3 and 3.7% to 2, 1.1, 0.9 and 2.4%, respectively, during the first year. However, the incidences of wasting and stunting were higher for the VLBW infants than for the LBW and NBW infants at 12 months (9.3% vs. 1.4%, p < 0.01; 9.3% vs. 1%, p < 0.01,respectively; 4.7% vs. 0.8%, p < 0.01, 4.7% vs. 0%, p < 0.01,respectively). Similar results were observed between SGA and AGA infants (8.7% vs. 1.5%, p < 0.01; 5.8% vs. 0.4%, p < 0.01). Logistic regression revealed SGA and VLBW as risk factors for poor growth (WLZ < -2SD) at 12 months (OR = 5.5, 95% CI: 2.1-14.8, p < 0.01: OR = 4.8, 95% CI: 1.8-12.8, p < 0.01, respectively).

CONCLUSION

The VLBW and SGA preterm infants showed significant catch-up growth during their first year of life. However, SGA and VLBW were risk factors for poor growth during the preterm infants' first year of life. Prophylactic iron supplementation in preterm infants appears to reduce the prevalence of anemia.

Iron Metabolism and Brain Development in Premature Infants

Iron is important for a remarkable array of essential functions during brain development, and it needs to be provided in adequate amounts, especially to preterm infants. In this review article, we provide an overview of iron metabolism and homeostasis at the cellular level, as well as its regulation at the mRNA translation level, and we emphasize the importance of iron for brain development in fetal and early life in preterm infants. We also review the risk factors for disrupted iron metabolism that lead to high risk of developing iron deficiency and subsequent adverse effects on neurodevelopment in preterm infants. At the other extreme, iron overload, which is usually caused by excess iron supplementation in iron-replete preterm infants, might negatively impact brain development or even induce brain injury. Maintaining the balance of iron during the fetal and neonatal periods is important, and thus iron status should be monitored routinely and evaluated thoroughly during the neonatal period or before discharge of preterm infants so that iron supplementation can be individualized.

Periodic limb movements and restless legs syndrome in children with a history of prematurity

INTRODUCTION

Little is known about the pediatric population at an increased risk of restless legs syndrome (RLS) and periodic limb movement disorder (PLMD). Polysomnographic data from the Caffeine for Apnea of Prematurity-Sleep (CAPS) study showed a high prevalence of elevated periodic limb movement index (PLMI) in a cohort of ex-preterm children, but the clinical importance of this finding, such as association with RLS, is unknown. We hypothesized that ex-preterm children would have a high prevalence of RLS and PLMD.

METHODS

Ex-preterm children enrolled in CAPS, now aged 5-12 years, completed home polysomnography (PSG) and standardized questionnaires. A diagnosis of RLS or PLMD was established by participants meeting the International Classification of Sleep Disorders, 3rd edition, criteria based on questionnaires and polysomnograms. The clinically available serum ferritin levels were assessed.

RESULTS

In total, 167 participants underwent polysomnography and completed all questionnaires. The overall prevalence of RLS was 14/167 (8.4%). An additional 13 subjects (7.8%) were found to have PLMD. Of the 26 participants who had PLMI > 5/h, seven (26.9%) had RLS and 13 (50%) had PLMD. The serum ferritin levels were <50 mcg/L (range -38.4) for all eight participants referred for testing.

CONCLUSIONS

Children with a history of prematurity have a high prevalence of RLS, particularly those with elevated periodic limb movements. Iron deficiency likely contributes to RLS and PLMD symptoms in this population. Clinicians evaluating ex-preterm children with sleep disturbances should evaluate for RLS and PLMD. Further studies including serum ferritin evaluation are required to confirm these findings.

Asthma as a disruption in iron homeostasis

Over several decades, asthma has evolved from being recognized as a single disease to include a diverse group of phenotypes with dissimilar natural histories, pathophysiologies, responses to treatment, and distinctive molecular pathways. With the application of Occam's razor to asthma, it is proposed that there is one cause underlying the numerous phenotypes of this disease and that the responsible molecular pathway is a deficiency of iron in the lung tissues. This deficiency can be either absolute (e.g. asthma in the neonate and during both pregnancy and menstruation) or functional (e.g. asthma associated with infections, smoking, and obesity). Comparable associations between asthma co-morbidity (e.g. eczema, urticaria, restless leg syndrome, and pulmonary hypertension) with iron deficiency support such a shared mechanistic pathway. Therapies directed at asthma demonstrate a capacity to impact iron homeostasis, further strengthening the relationship. Finally, pathophysiologic events producing asthma, including inflammation, increases in Th2 cells, and muscle contraction, can correlate with iron availability. Recognition of a potential association between asthma and an absolute and/or functional iron deficiency suggests specific therapeutic interventions including inhaled iron.

Micronutrient supplementation adherence and influence on the prevalences of anemia and iron, zinc and vitamin A deficiencies in preemies with a corrected age of six months

OBJECTIVE

To analyze adherence to the recommended iron, zinc and multivitamin supplementation guidelines for preemies, the factors associated with this adherence, and the influence of adherence on the occurrence of anemia and iron, zinc and vitamin A deficiencies.

METHODS

This prospective cohort study followed 58 preemies born in 2014 until they reached six months corrected age. The preemies were followed at a referral secondary health service and represented 63.7% of the preterm infants born that year. Outcomes of interest included high or low adherence to iron, zinc and multivitamin supplementation guidelines; prevalence of anemia; and prevalences of iron, zinc, and vitamin A deficiencies. The prevalence ratios were calculated by Poisson regression.

RESULTS

Thirty-eight (65.5%) preemies presented high adherence to micronutrient supplementation guidelines. At six months of corrected age, no preemie had vitamin A deficiency. The prevalences of anemia, iron deficiency and zinc deficiency were higher in the low-adherence group but also concerning in the high-adherence group. Preemies with low adherence to micronutrient supplementation guidelines were 2.5 times more likely to develop anemia and 3.1 times more likely to develop zinc deficiency. Low maternal education level increased the likelihood of nonadherence to all three supplements by 2.2 times.

CONCLUSIONS

Low maternal education level was independently associated with low adherence to iron, zinc and vitamin A supplementation guidelines in preemies, which impacted the prevalences of anemia and iron and zinc deficiencies at six months of corrected age.

Early and late Iron supplementation for low birth weight infants: a meta-analysis

Background

Iron deficiency in infancy is associated with a range of clinical and developmentally important issues. Currently, it is unclear what is the optimal timing to administer prophylactic enteral iron supplementation in preterm and very low birth weight infants. The objective of this meta-analysis was to evaluate early compared with late iron supplementation in low birth weight infants.

Methods

PubMed and Cochrane Library databases were searched up to May 10, 2014 for studies that compared the benefit of early and late iron supplementation in infants of low birth weight. Sensitivity analysis was carried out using the leave one-out approach and the quality of the included data was assessed.

Results

The data base search and detailed review identified four studies that were included in the meta-analysis. The number of included patients was 246 (n = 121 for early supplementation and n = 125 for late supplementation) and the majority were premature infants. Across studies, early supplementation ranged from as early as enteral feeding was tolerated to 3 weeks, and late supplementation ranged from 4 weeks to about 60 days. Early treatment was associated with significantly smaller decreases in serum ferritin and hemoglobin levels (P < 0.001). In addition, the rate of blood transfusions was lower with early compared with late iron supplementation (P = 0.022). There was no difference between early and late supplementation in the number of patients with nectorizing enteroclitis (>bell stage 2) (P = 0.646). Sensitivity analysis indicated no one study overly influenced the findings and that the data was reliable.

Conclusion

In conclusion, early iron supplementation resulted in less a decrease in serum ferritin and hemoglobin levels in infants with low birth rate. However, caution should be used when treating infants with iron so as not to result in iron overload and possibly negative long-term effects on neurodevelopment.

Iron supplementation until 6 months protects marginally low-birth-weight infants from iron deficiency during their first year of life

OBJECTIVES

Low-birth-weight (LBW) infants (<2500 g) have an increased risk of iron deficiency (ID) during their first 6 months of life. The optimal dose and duration of iron supplementation to LBW infants are, however, unknown. The objective of the present study was to investigate the long-term effect on iron status and growth in marginally LBW (2000-2500 g) infants, of iron supplements given until 6 months of life.

METHODS

In a randomized controlled trial, 285 healthy marginally LBW infants received 0, 1, or 2 mg · kg(-1) · day(-1) of iron supplements from 6 weeks to 6 months of age. At 12 months and 3.5 years of life we measured length, weight, head circumference, and indicators of iron status (hemoglobin, ferritin, mean corpuscular volume, and transferrin saturation) and assessed the prevalence of iron depletion, functional ID, and ID anemia.

RESULTS

At 12 months of age, there was a significant difference in ferritin between the groups (P = 0.006). Furthermore, there was a significant difference in the prevalence of iron depletion (23.7%, 10.6%, and 6.8%, respectively, in the placebo, 1-mg, and 2-mg groups, P = 0.009) and similar nonsignificant trends for functional ID and ID anemia. At 3.5 years of life there were no significant differences in iron status and the mean prevalence of iron depletion was 3.2%. Anthropometric data were not affected by the intervention.

CONCLUSIONS

Iron supplements with 2 mg · kg(-1) · day(-1) until 6 months of life effectively reduces the risk of ID during the first 12 months of life and is an effective intervention for preventing early ID in marginally LBW infants.