Division of Women & Child Health, The Aga Khan University, Karachi, Pakistan.
BMC Public Health. 2011 Apr 13;11 Suppl 3(Suppl 3):S21. doi: 10.1186/1471-2458-11-S3-S21.
Iron deficiency is the most prevalent nutrient deficiency in the world, particularly during pregnancy. According to the literature, anemia, particularly severe anemia, is associated with increased risk of maternal mortality. It also puts mothers at risk of multiple perinatal complications. Numerous studies in the past have evaluated the impact of supplementation with iron and iron-folate but data regarding the efficacy and quality of evidence of these interventions are lacking. This article aims to address the impact of iron with and without folate supplementation on maternal anemia and provides outcome specific quality according to the Child Health Epidemiology Reference Group (CHERG) guidelines.
We conducted a systematic review of published randomized and quasi-randomized trials on PubMed and the Cochrane Library as per the CHERG guidelines. The studies selected employed daily supplementation of iron with or without folate compared with no intervention/placebo, and also compared intermittent supplementation with the daily regimen. The studies were abstracted and graded according to study design, limitations, intervention specifics and outcome effects. CHERG rules were then applied to evaluate the impact of these interventions on iron deficiency anemia during pregnancy. Recommendations were made for the Lives Saved Tool (LiST).
After screening 3550 titles, 31 studies were selected for assessment using CHERG criteria. Daily iron supplementation resulted in 73% reduction in the incidence of anemia at term (RR = 0.27; 95% CI: 0.17 - 0.42; random effects model) and 67% reduction in iron deficiency anemia at term (RR = 0.33; 95% CI: 0.16 - 0.69; random model) compared to no intervention/placebo. For this intervention, both these outcomes were graded as 'moderate' quality evidence. Daily supplementation with iron-folate was associated with 73% reduction in anemia at term (RR = 0.27; 95% CI: 0.12 - 0.56; random model) with a quality grade of 'moderate'. The effect of the same intervention on iron deficiency anemia was non-significant (RR = 0.43; 95% CI: 0.17 - 1.09; random model) and was graded as 'low' quality evidence. There was no difference in rates of anemia at term with intermittent iron-folate vs. daily iron-folate supplementation (RR = 1.61; 95% CI: 0.82 -3.14; random model).
Applying the CHERG rules, we recommend a 73% reduction in anemia at term with daily iron (alone) supplementation or iron/folate (combined) vs. no intervention or placebo; for inclusion in the LiST model. Given the paucity of studies of intermittent iron or iron-folate supplementation, especially in developing countries, we recommend further evaluation of this intervention in comparison with daily supplementation regimen.
缺铁是世界上最普遍的营养缺乏症,尤其是在怀孕期间。根据文献记载,贫血,尤其是严重贫血,会增加产妇死亡的风险。它还使母亲面临多种围产期并发症的风险。过去有许多研究评估了铁和铁叶酸补充的影响,但缺乏关于这些干预措施的疗效和证据质量的数据。本文旨在探讨铁和铁叶酸补充对产妇贫血的影响,并根据儿童健康流行病学参考组(CHERG)指南提供特定结局的质量证据。
我们按照 CHERG 指南,在 PubMed 和 Cochrane 图书馆中对已发表的随机和准随机试验进行了系统综述。所选研究采用每日补充铁和/或铁叶酸与不干预/安慰剂进行比较,也比较了间歇性补充与每日方案。根据研究设计、局限性、干预措施细节和结局效果对研究进行了摘录和分级。然后应用 CHERG 规则来评估这些干预措施对妊娠期间缺铁性贫血的影响。为 Lives Saved Tool(LiST)提出了建议。
在筛选了 3550 个标题后,使用 CHERG 标准评估了 31 项研究。与不干预/安慰剂相比,每日铁补充可使足月时贫血的发生率降低 73%(RR = 0.27;95%CI:0.17 - 0.42;随机效应模型),并使足月时缺铁性贫血的发生率降低 67%(RR = 0.33;95%CI:0.16 - 0.69;随机模型)。对于这种干预措施,这两个结局的证据质量均为“中度”。与不干预/安慰剂相比,每日补充铁叶酸与足月时贫血发生率降低 73%相关(RR = 0.27;95%CI:0.12 - 0.56;随机模型),证据质量等级为“中度”。同一干预措施对缺铁性贫血的影响无统计学意义(RR = 0.43;95%CI:0.17 - 1.09;随机模型),证据质量等级为“低”。与每日铁叶酸补充相比,间歇性铁叶酸补充与足月时贫血的发生率无差异(RR = 1.61;95%CI:0.82 -3.14;随机模型)。
根据 CHERG 规则,我们建议每日铁(单独)补充或铁/叶酸(联合)补充可使足月时贫血发生率降低 73%,与不干预或安慰剂相比;应将其纳入 LiST 模型。鉴于间歇性铁或铁叶酸补充的研究较少,尤其是在发展中国家,我们建议进一步评估这种干预措施与每日补充方案的比较。