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2.
Lancet Haematol ; 10(9): e756-e766, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37482061

RESUMO

BACKGROUND: Anaemia in pregnancy is a global health problem with associated maternal and neonatal morbidity and mortality. We aimed to investigate the association between maternal haemoglobin concentrations during pregnancy and the risk of adverse maternal and neonatal outcomes. METHODS: In this prospective, observational, multinational, INTERBIO-21st fetal study conducted at maternity units in Brazil, Kenya, Pakistan, South Africa, and the UK, we enrolled pregnant women (aged ≥18 years, BMI <35 kg/m2, natural conception, and singleton pregnancy) who initiated antenatal care before 14 weeks' gestation. At each 5±1 weekly visit until delivery, information was collected about the pregnancy, as well as the results of blood tests taken as part of routine antenatal care, including haemoglobin values. The outcome measures were maternal (gestational diabetes, pregnancy-induced hypertension, and preterm premature rupture of membranes) and neonatal outcomes (small for gestational age, preterm birth, and acute respiratory distress syndrome). FINDINGS: Between Feb 8, 2012, and Nov 30, 2019, 2069 women (mean age 30·7 years [SD 5·0]) had at least one routinely haemoglobin concentration measured at 14-40 weeks' gestation, contributing 4690 haemoglobin measurements for the analysis. Compared with a haemoglobin cutoff of 110 g/L, the risk was increased more than two-fold for pregnancy-induced hypertension at haemoglobin concentrations of 170 g/L (risk ratio [RR] 2·29 [95% CI 1·19-4·39]) and higher, for preterm birth at haemoglobin concentrations of 70 g/L (RR 2·04 [95% CI 1·20-3·48]) and 165 g/L (RR 2·06 [95% CI 1·41-3·02]), and for acute respiratory distress syndrome at haemoglobin concentrations of 165 g/L (RR 2·84 [95% CI 1·51-5·35]). Trimester-specific results are also presented. INTERPRETATION: Our data suggests that the current WHO haemoglobin cutoffs are associated with reduced risk of adverse maternal and neonatal outcomes. The current haemoglobin concentration cutoffs during pregnancy should not only consider thresholds for low haemoglobin concentrations that are associated with adverse outcomes but also define a threshold for high haemoglobin concentrations given the U-shaped relationship between haemoglobin concentration and adverse neonatal and maternal outcomes. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Hipertensão Induzida pela Gravidez , Nascimento Prematuro , Síndrome do Desconforto Respiratório , Gravidez , Feminino , Recém-Nascido , Humanos , Adolescente , Adulto , Nascimento Prematuro/epidemiologia , Cuidado Pré-Natal , Estudos Prospectivos
3.
BMC Public Health ; 23(1): 1454, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37518003

RESUMO

BACKGROUND: Anaemia is a reduction in haemoglobin concentration below a threshold, resulting from various factors including severe blood loss during and after childbirth. Symptoms of anaemia include fatigue and weakness, among others, affecting health and quality of life. Anaemic pregnant women have an increased risk of premature delivery, a low-birthweight infant, and postpartum depression. They are also more likely to have anaemia in the postpartum period which can lead to an ongoing condition and affect subsequent pregnancies. In 2019 nearly 37% of pregnant women globally had anaemia, and estimates suggest that 50-80% of postpartum women in low- and middle-income countries have anaemia, but currently there is no standard measurement or classification for postpartum anaemia. METHODS: A rapid landscape review was conducted to identify and characterize postpartum anaemia measurement searching references within three published systematic reviews of anaemia, including studies published between 2012 and 2021. We then conducted a new search for relevant literature from February 2021 to April 2022 in EMBASE and MEDLINE using a similar search strategy as used in the published reviews. RESULTS: In total, we identified 53 relevant studies. The timing of haemoglobin measurement ranged from within the immediate postpartum period to over 6 weeks. The thresholds used to diagnose anaemia in postpartum women varied considerably, with < 120, < 110, < 100 and < 80 g/L the most frequently reported. Other laboratory results frequently reported included ferritin and transferrin receptor. Clinical outcomes reported in 32 out of 53 studies included postpartum depression, quality of life, and fatigue. Haemoglobin measurements were performed in a laboratory, although it is unclear from the studies if venous samples and automatic analysers were used in all cases. CONCLUSIONS: This review demonstrates the need for improving postpartum anaemia measurement given the variability observed in published measures. With the high prevalence of anaemia, the relatively simple treatment for non-severe cases of iron deficiency anaemia, and its importance to public health with multi-generational effects, it is crucial to develop common measures for women in the postpartum period and promote rapid uptake and reporting.


Assuntos
Anemia Ferropriva , Anemia , Depressão Pós-Parto , Feminino , Humanos , Gravidez , Ferro , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Qualidade de Vida , Anemia/diagnóstico , Anemia/epidemiologia , Período Pós-Parto , Fadiga , Hemoglobinas
4.
Ann N Y Acad Sci ; 1524(1): 5-9, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37067421

RESUMO

The World Health Organization (WHO) announced in 2021 a commitment to develop a comprehensive framework for integrated action on the prevention, diagnosis, and management of anemia and to establish an Anaemia Action Alliance to support the implementation of the framework. WHO commissioned four background papers to provide reflections about the most pressing issues to be addressed for accelerating reductions in the prevalence of anemia. Here, we provide a complete vision of the framework.


Assuntos
Anemia , Humanos , Anemia/diagnóstico , Anemia/prevenção & controle , Organização Mundial da Saúde
5.
Ann N Y Acad Sci ; 1524(1): 37-50, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37061792

RESUMO

Accurate and affordable tools for diagnosing anemia and its main determinants are essential for understanding the magnitude and distribution of the problem and the appropriate interventions needed for its timely prevention and treatment. The objective of this review is to address methods, equipment, and sample-related and quality control aspects of hemoglobin measurement for anemia diagnosis. Also, other iron-, infectious-, and genetic-related causes of anemia are addressed in individuals and populations. The best practice for hemoglobin determination is the use of venous blood, analyzed on automated hematology analyzers, with high-quality control measures in place. The importance of a correct anemia diagnosis is highlighted by the cost of a misdiagnosis. A false-negative diagnosis may result in missing out and not treating anemia, its causes, and its adverse effects. On the other hand, a false-positive diagnosis may result in the provision of unneeded treatment or referral for expensive laboratory tests to determine a cause of anemia, wasting valuable resources and risking causing harm. At the individual level, clinicians must understand the causes of absolute and functional anemia to diagnose and treat anemia at the clinical level. Actions toward anemia diagnosis and control at public health levels require global, regional, and country actions that should cover general and context-specific characteristics.


Assuntos
Anemia , Humanos , Anemia/diagnóstico , Anemia/terapia , Ferro , Causalidade , Nível de Saúde , Hemoglobinas/análise
6.
Cochrane Database Syst Rev ; 9: CD013092, 2021 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-34564844

RESUMO

BACKGROUND: Anaemia is a prevalent health problem worldwide. Some types are preventable or controllable with iron supplementation (pills or drops), fortification (sprinkles or powders containing iron added to food) or improvements to dietary diversity and quality (e.g. education or counselling). OBJECTIVES: To summarise the evidence from systematic reviews regarding the benefits or harms of nutrition-specific interventions for preventing and controlling anaemia in anaemic or non-anaemic, apparently healthy populations throughout the life cycle. METHODS: In August 2020, we searched MEDLINE, Embase and 10 other databases for systematic reviews of randomised controlled trials (RCTs) in anaemic or non-anaemic, apparently healthy populations. We followed standard Cochrane methodology, extracting GRADE ratings where provided. The primary outcomes were haemoglobin (Hb) concentration, anaemia, and iron deficiency anaemia (IDA); secondary outcomes were iron deficiency (ID), severe anaemia and adverse effects (e.g. diarrhoea, vomiting). MAIN RESULTS: We included 75 systematic reviews, 33 of which provided GRADE assessments; these varied between high and very low. Infants (6 to 23 months; 13 reviews) Iron supplementation increased Hb levels and reduced the risk of anaemia and IDA in two reviews. Iron fortification of milk or cereals, multiple-micronutrient powder (MMNP), home fortification of complementary foods, and supplementary feeding increased Hb levels and reduced the risk of anaemia in six reviews. In one review, lipid-based nutrient supplementation (LNS) reduced the risk of anaemia. In another, caterpillar cereal increased Hb levels and IDA prevalence. Food-based strategies (red meat and fortified cow's milk, beef) showed no evidence of a difference (1 review). Preschool and school-aged children (2 to 10 years; 8 reviews) Daily or intermittent iron supplementation increased Hb levels and reduced the risk of anaemia and ID in two reviews. One review found no evidence of difference in Hb levels, but an increased risk of anaemia and ID for the intermittent regime. All suggested that zinc plus iron supplementation versus zinc alone, multiple-micronutrient (MMN)-fortified beverage versus control, and point-of-use fortification of food with iron-containing micronutrient powder (MNP) versus placebo or no intervention may increase Hb levels and reduce the risk of anaemia and ID. Fortified dairy products and cereal food showed no evidence of a difference on the incidence of anaemia (1 review). Adolescent children (11 to 18 years; 4 reviews) Compared with no supplementation or placebo, five types of iron supplementation may increase Hb levels and reduce the risk of anaemia (3 reviews). One review on prevention found no evidence of a difference in anaemia incidence on iron supplementation with or without folic acid, but Hb levels increased. Another suggested that nutritional supplementation and counselling reduced IDA. One review comparing MMN fortification with no fortification observed no evidence of a difference in Hb levels. Non-pregnant women of reproductive age (19 to 49 years; 5 reviews) Two reviews suggested that iron therapy (oral, intravenous (IV), intramuscular (IM)) increased Hb levels; one showed that iron folic acid supplementation reduced anaemia incidence; and another that daily iron supplementation with or without folic acid or vitamin C increased Hb levels and reduced the risk of anaemia and ID. No review reported interventions related to fortification or dietary diversity and quality. Pregnant women of reproductive age (15 to 49 years; 23 reviews) One review apiece suggested that: daily iron supplementation with or without folic acid increased Hb levels in the third trimester or at delivery and in the postpartum period, and reduced the risk of anaemia, IDA and ID in the third trimester or at delivery; intermittent iron supplementation had no effect on Hb levels and IDA, but increased the risk of anaemia at or near term and ID, and reduced the risk of side effects; vitamin A supplementation alone versus placebo, no intervention or other micronutrient might increase maternal Hb levels and reduce the risk of maternal anaemia; MMN with iron and folic acid versus placebo reduced the risk of anaemia; supplementation with oral bovine lactoferrin versus oral ferrous iron preparations increased Hb levels and reduced gastrointestinal side effects; MNP for point-of-use fortification of food versus iron and folic acid supplementation might decrease Hb levels at 32 weeks' gestation and increase the risk of anaemia; and LNS versus iron or folic acid and MMN increased the risk of anaemia. Mixed population (all ages; 22 reviews) Iron supplementation versus placebo or control increased Hb levels in healthy children, adults, and elderly people (4 reviews). Hb levels appeared to increase and risk of anaemia and ID decrease in two reviews investigating MMN fortification versus placebo or no treatment, iron fortified flour versus control, double fortified salt versus iodine only fortified salt, and rice fortification with iron alone or in combination with other micronutrients versus unfortified rice or no intervention. Each review suggested that fortified versus non-fortified condiments or noodles, fortified (sodium iron ethylenediaminetetraacetate; NaFeEDTA) versus non-fortified soy sauce, and double-fortified salt versus control salt may increase Hb concentration and reduce the risk of anaemia. One review indicated that Hb levels increased for children who were anaemic or had IDA and received iron supplementation, and decreased for those who received dietary interventions. Another assessed the effects of foods prepared in iron pots, and found higher Hb levels in children with low-risk malaria status in two trials, but no difference when comparing food prepared in non-cast iron pots in a high-risk malaria endemicity mixed population. There was no evidence of a difference for adverse effects. Anaemia and malaria prevalence were rarely reported. No review focused on women aged 50 to 65 years plus or men (19 to 65 years plus). AUTHORS' CONCLUSIONS: Compared to no treatment, daily iron supplementation may increase Hb levels and reduce the risk of anaemia and IDA in infants, preschool and school-aged children and pregnant and non-pregnant women. Iron fortification of foods in infants and use of iron pots with children may have prophylactic benefits for malaria endemicity low-risk populations. In any age group, only a limited number of reviews assessed interventions to improve dietary diversity and quality. Future trials should assess the effects of these types of interventions, and consider the requirements of different populations.


Assuntos
Anemia Ferropriva , Anemia , Adolescente , Adulto , Idoso , Anemia/epidemiologia , Anemia/prevenção & controle , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Animais , Criança , Suplementos Nutricionais , Feminino , Alimentos Fortificados , Humanos , Ferro , Estágios do Ciclo de Vida , Masculino , Micronutrientes , Pessoa de Meia-Idade , Gravidez , Revisões Sistemáticas como Assunto , Adulto Jovem
7.
Cochrane Database Syst Rev ; 5: CD011817, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34028001

RESUMO

BACKGROUND: Reference standard indices of iron deficiency and iron overload are generally invasive, expensive, and can be unpleasant or occasionally risky. Ferritin is an iron storage protein and its concentration in the plasma or serum reflects iron stores; low ferritin indicates iron deficiency, while elevated ferritin reflects risk of iron overload. However, ferritin is also an acute-phase protein and its levels are elevated in inflammation and infection. The use of ferritin as a diagnostic test of iron deficiency and overload is a common clinical practice. OBJECTIVES: To determine the diagnostic accuracy of ferritin concentrations (serum or plasma) for detecting iron deficiency and risk of iron overload in primary and secondary iron-loading syndromes. SEARCH METHODS: We searched the following databases (10 June 2020): DARE (Cochrane Library) Issue 2 of 4 2015, HTA (Cochrane Library) Issue 4 of 4 2016, CENTRAL (Cochrane Library) Issue 6 of 12 2020, MEDLINE (OVID) 1946 to 9 June 2020, Embase (OVID) 1947 to week 23 2020, CINAHL (Ebsco) 1982 to June 2020, Web of Science (ISI) SCI, SSCI, CPCI-exp & CPCI-SSH to June 2020, POPLINE 16/8/18, Open Grey (10/6/20), TRoPHI (10/6/20), Bibliomap (10/6/20), IBECS (10/6/20), SCIELO (10/6/20), Global Index Medicus (10/6/20) AIM, IMSEAR, WPRIM, IMEMR, LILACS (10/6/20), PAHO (10/6/20), WHOLIS 10/6/20, IndMED (16/8/18) and Native Health Research Database (10/6/20). We also searched two trials registers and contacted relevant organisations for unpublished studies. SELECTION CRITERIA: We included all study designs seeking to evaluate serum or plasma ferritin concentrations measured by any current or previously available quantitative assay as an index of iron status in individuals of any age, sex, clinical and physiological status from any country. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods. We designed the data extraction form to record results for ferritin concentration as the index test, and bone marrow iron content for iron deficiency and liver iron content for iron overload as the reference standards. Two other authors further extracted and validated the number of true positive, true negative, false positive, false negative cases, and extracted or derived the sensitivity, specificity, positive and negative predictive values for each threshold presented for iron deficiency and iron overload in included studies. We assessed risk of bias and applicability using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. We used GRADE assessment to enable the quality of evidence and hence strength of evidence for our conclusions. MAIN RESULTS: Our search was conducted initially in 2014 and updated in 2017, 2018 and 2020 (10 June). We identified 21,217 records and screened 14,244 records after duplicates were removed. We assessed 316 records in full text. We excluded 190 studies (193 records) with reasons and included 108 studies (111 records) in the qualitative and quantitative analysis. There were 11 studies (12 records) that we screened from the last search update and appeared eligible for a future analysis. We decided to enter these as awaiting classification. We stratified the analysis first by participant clinical status: apparently healthy and non-healthy populations. We then stratified by age and pregnancy status as: infants and children, adolescents, pregnant women, and adults. Iron deficiency We included 72 studies (75 records) involving 6059 participants. Apparently healthy populations Five studies screened for iron deficiency in people without apparent illness. In the general adult population, three studies reported sensitivities of 63% to 100% at the optimum cutoff for ferritin, with corresponding specificities of 92% to 98%, but the ferritin cutoffs varied between studies. One study in healthy children reported a sensitivity of 74% and a specificity of 77%. One study in pregnant women reported a sensitivity of 88% and a specificity of 100%. Overall confidence in these estimates was very low because of potential bias, indirectness, and sparse and heterogenous evidence. No studies screened for iron overload in apparently healthy people. People presenting for medical care There were 63 studies among adults presenting for medical care (5042 participants). For a sample of 1000 subjects with a 35% prevalence of iron deficiency (of the included studies in this category) and supposing a 85% specificity, there would be 315 iron-deficient subjects correctly classified as having iron deficiency and 35 iron-deficient subjects incorrectly classified as not having iron deficiency, leading to a 90% sensitivity. Thresholds proposed by the authors of the included studies ranged between 12 to 200 µg/L. The estimated diagnostic odds ratio was 50. Among non-healthy adults using a fixed threshold of 30 µg/L (nine studies, 512 participants, low-certainty evidence), the pooled estimate for sensitivity was 79% with a 95% confidence interval of (58%, 91%) and specificity of 98%, with a 95% confidence interval of (91%, 100%). The estimated diagnostic odds ratio was 140, a relatively highly informative test. Iron overload We included 36 studies (36 records) involving 1927 participants. All studies concerned non-healthy populations. There were no studies targeting either infants, children, or pregnant women. Among all populations (one threshold for males and females; 36 studies, 1927 participants, very low-certainty evidence): for a sample of 1000 subjects with a 42% prevalence of iron overload (of the included studies in this category) and supposing a 65% specificity, there would be 332 iron-overloaded subjects correctly classified as having iron overload and 85 iron-overloaded subjects incorrectly classified as not having iron overload, leading to a 80% sensitivity. The estimated diagnostic odds ratio was 8. AUTHORS' CONCLUSIONS: At a threshold of 30 micrograms/L, there is low-certainty evidence that blood ferritin concentration is reasonably sensitive and a very specific test for iron deficiency in people presenting for medical care. There is very low certainty that high concentrations of ferritin provide a sensitive test for iron overload in people where this condition is suspected. There is insufficient evidence to know whether ferritin concentration performs similarly when screening asymptomatic people for iron deficiency or overload.


Assuntos
Anemia Ferropriva/sangue , Ferritinas/sangue , Sobrecarga de Ferro/sangue , Adolescente , Adulto , Idoso , Anemia Ferropriva/diagnóstico , Viés , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Sobrecarga de Ferro/diagnóstico , Masculino , Pessoa de Meia-Idade , Gravidez , Gestantes , Sensibilidade e Especificidade , Adulto Jovem
8.
Viruses ; 13(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477428

RESUMO

We systematically searched regional and international databases and screened 1658 non-duplicate records describing women with suspected or confirmed ZIKV infection, intending to breastfeed or give breast milk to an infant to examine the potential of mother-to-child transmission of Zika virus (ZIKV) through breast milk or breastfeeding-related practices. Fourteen studies met our inclusion criteria and inform this analysis. These studies reported on 97 mother-children pairs who provided breast milk for ZIKV assessment. Seventeen breast milk samples from different women were found positive for ZIKV via RT-PCR, and ZIKV replication was found in cell cultures from five out of seven breast milk samples from different women. Only three out of six infants who had ZIKV infection were breastfed, no evidence of clinical complications was found to be associated with ZIKV RNA in breast milk. This review updates our previous report by including 12 new articles, in which we found no evidence of ZIKV mother-to-child transmission through breast milk intake or breastfeeding. As the certainty of the present evidence is low, additional studies are still warranted to determine if ZIKV can be transmitted through breastfeeding.


Assuntos
Aleitamento Materno , Transmissão Vertical de Doenças Infecciosas , Leite Humano/virologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissão , Zika virus , Aleitamento Materno/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Vigilância em Saúde Pública , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecção por Zika virus/virologia
9.
Ann N Y Acad Sci ; 1493(1): 59-74, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33432622

RESUMO

Calcium intake is low in many countries, especially in low-income countries. Our objective was to perform a simulation exercise on the impact, effectiveness, and safety of a flour fortification strategy using the Intake Modelling, Assessment, and Planning Program. Modeling of calcium fortification scenarios was performed with available dietary intake databases from Argentina, Bangladesh, Italy, the Lao People's Democratic Republic (Lao PDR), Uganda, Zambia, and the United States. This theoretical exercise showed that simulating a fortification with 156 mg of calcium per 100 g of flour would decrease the prevalence of low calcium intake, and less than 2% of the individuals would exceed the recommended calcium upper limit (UL) in Argentina, Italy, Uganda, and Zambia. Bangladesh and the Lao PDR showed little impact, as flour intake is uncommon. By contrast, in the United States, this strategy would lead to some population groups exceeding the UL. This exercise should be replicated and adapted to each country, taking into account the updated prevalence of calcium inadequacy, flour consumption, and technical compatibility between calcium and the flour-type candidate for fortification. A fortification plan should consider the impact on all age groups to avoid the risk of exceeding the upper levels of calcium intake.


Assuntos
Cálcio da Dieta/administração & dosagem , Farinha , Alimentos Fortificados , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Simulação por Computador , Bases de Dados Factuais , Países em Desenvolvimento , Registros de Dieta , Ingestão de Alimentos , Feminino , Farinha/análise , Alimentos Fortificados/análise , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pobreza , Gravidez , Recomendações Nutricionais , Adulto Jovem
10.
Ann N Y Acad Sci ; 1485(1): 3-21, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32986887

RESUMO

Low calcium intake is common worldwide and can result in nutritional rickets in children and osteomalacia in adults. Calcium-fortified foods could improve calcium intake. However, there is limited calcium fortification experience, with technical and practical issues that may hamper its adoption. The objective of this landscape review is to summarize these issues to help policymakers guide the planning and design of calcium fortification as a public health strategy. One challenge is the low bioavailability of calcium salts (∼20-40%); thus, large amounts need to be added to food to have a meaningful impact. Solubility is important when fortifying liquids and acidic foods. Calcium salts could change the flavor, color, and appearance of the food and may account for 70-90% of the total fortification cost. Safety is key to avoid exceeding the recommended intake; so the amount of added calcium should be based on the target calcium intake and the gap between inadequate and adequate levels. Monitoring includes the quality of the fortified food and population calcium intake using dietary assessment methods. Calcium fortification should follow regulations, implemented in an intersectorial way, and be informed by the right to health and equity. This information may help guide and plan this public health strategy.


Assuntos
Cálcio , Alimentos Fortificados , Política Nutricional , Saúde Pública , Dieta , Humanos , Necessidades Nutricionais
11.
Ann N Y Acad Sci ; 1484(1): 32-54, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32860259

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19) is caused by infection with a novel coronavirus strain, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). At present, there is limited information on potential transmission of the infection from mother to child, particularly through breast milk and breastfeeding. Here, we provide a living systematic review to capture information that might necessitate changes in the guidance on breast milk and breastfeeding given the uncertainty in this area. Our search retrieved 19,414 total records; 605 were considered for full-text eligibility and no ongoing trials were identified. Our review includes 340 records, 37 with breast milk samples and 303 without. The 37 articles with analyzed breast milk samples reported on 77 mothers who were breastfeeding their children; among them, 19 of 77 children were confirmed COVID-19 cases based on RT-PCR assays, including 14 neonates and five older infants. Nine of the 68 analyzed breast milk samples from mothers with COVID-19 were positive for SARS-CoV-2 RNA; of the exposed infants, four were positive and two were negative for COVID-19. Currently, there is no evidence of SARS-CoV-2 transmission through breast milk. Studies are needed with longer follow-up periods that collect data on infant feeding practices and on viral presence in breast milk.


Assuntos
Aleitamento Materno , COVID-19 , Transmissão Vertical de Doenças Infecciosas , Leite Humano/virologia , SARS-CoV-2/metabolismo , COVID-19/epidemiologia , COVID-19/metabolismo , COVID-19/transmissão , Criança , Feminino , Humanos , Lactente , Recém-Nascido
12.
Ann N Y Acad Sci ; 1484(1): 55-73, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949062

RESUMO

Low dietary calcium is very common in many populations, contributing to nutritional rickets/osteomalacia in children/adults and increasing the risk of several health problems. Calcium is a nutrient of concern as the recommended nutrient requirements are difficult to meet in the absence of dairy products. The provision of culturally acceptable calcium-fortified foods may improve calcium intake when it is a feasible and cost-effective strategy in a particular setting. This landscape review was conducted in 2019 and describes current calcium fortification efforts and lessons learned from these experiences. Worldwide, the United Kingdom is the only country where calcium fortification of wheat flour is mandatory. It is estimated that this fortified staple ingredient contributes to 13-14% of calcium intake of the British population. Other items voluntary fortified with calcium include maize flour, rice, and water. Current calcium fortification programs may lack qualified personnel/training, clear guidelines on implementation, regulation, monitoring/evaluation, and functional indicators. Also, the cost of calcium premix is high and the target groups may be hard to reach. There is a lack of rigorous evaluation, particularly in settings with multiple micronutrient programs implemented simultaneously, with low quality of the evidence. Further research is needed to assess the impact of calcium fortification programs.


Assuntos
Cálcio da Dieta , Cálcio/metabolismo , Alimentos Fortificados/normas , Necessidades Nutricionais , Cálcio/química , Análise Custo-Benefício , Farinha/normas , Humanos , Oryza/química , Triticum/química , Reino Unido/epidemiologia , Água/química , Zea mays/química
13.
EClinicalMedicine ; 29-30: 100660, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33437954

RESUMO

BACKGROUND: Anaemia in pregnancy is a global health problem with associated morbidity and mortality. METHODS: A secondary analysis of prospective, population-based study from 2009 to 2016 to generate maternal haemoglobin normative centiles in uncomplicated pregnancies in women receiving optimal antenatal care. Pregnant women were enrolled <14 weeks' gestation in the Fetal Growth Longitudinal Study (FGLS) of the INTERGROWTH-21st Project which involved eight geographically diverse urban areas in Brazil, China, India, Italy, Kenya, Oman, United Kingdom and United States. At each 5 ± 1 weekly visit until delivery, information was collected about the pregnancy, as well as the results of blood tests taken as part of routine antenatal care that complemented the study's requirements, including haemoglobin values. FINDINGS: A total of 3502 (81%) of 4321 women who delivered a live, singleton newborn with no visible congenital anomalies, contributed at least one haemoglobin value. Median haemoglobin concentrations ranged from 114.6 to 121.4 g/L, 94 to 103 g/L at the 3rd centile, and from 135 to 141 g/L at the 97th centile. The lowest values were seen between 31 and 32 weeks' gestation, representing a mean drop of 6.8 g/L compared to 14 weeks' gestation. The percentage variation in maternal haemoglobin within-site was 47% of the total variance compared to 13% between sites. INTERPRETATION: We have generated International, gestational age-specific, smoothed centiles for maternal haemoglobin concentration compatible with better pregnancy outcomes, as well as adequate neonatal and early childhood morbidity, growth and development up to 2 years of age. FUNDING: Bill & Melinda Gates Foundation Grant number 49038.

14.
Ann N Y Acad Sci ; 1450(1): 5-14, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31006883

RESUMO

Anemia is an important public health problem that negatively affects health of individuals and economic potential of populations. An accurate case definition is critical for understanding burden and epidemiology of anemia, for planning public health interventions, and for clinical investigation and treatment of patients. The current threshold hemoglobin concentrations for diagnosis of anemia were proposed in 1968 and based on studies predominantly of Caucasian adult populations in Europe and North America. The World Health Organization is undertaking a project to review global guidelines for anemia. We describe the process of obtaining input from technical experts, researchers, blood bank experts, policy makers, and program implementers to identify key information or knowledge gaps for anemia diagnosis. From this scoping exercise, six priority areas were identified on diverse topics related to the use and interpretation of hemoglobin concentrations to diagnose anemia in individuals and populations. A call for authors was conducted to produce background, review, and research papers across priority topics. This paper summarizes the first technical meeting, which included commissioned papers as well as case studies, describes key data gaps identified, and describes the next steps in the guideline development process to assess available evidence and define knowledge gaps to improve anemia characterization.


Assuntos
Anemia/diagnóstico , Hemoglobinas/análise , Anemia/sangue , Saúde Global , Humanos , Organização Mundial da Saúde
15.
Ann N Y Acad Sci ; 1446(1): 5-20, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30291627

RESUMO

The excessive consumption of certain vitamins and minerals could have deleterious consequences on health and development of individuals and populations. Simultaneous micronutrient-delivery interventions could be challenging in terms of safety as the target populations may overlap, posing a risk of excessive intake of certain micronutrients. The Evidence and Programme Guidance Unit of the Department of Nutrition for Health and Development of the World Health Organization convened a technical consultation on the risk of excessive intake of vitamins and minerals delivered through public health interventions in October 2017. The technical consultation's working groups identified important and emerging technical issues, lessons learned, and research priorities related to (1) planning, implementing, monitoring, and evaluating nutrition programs for the detection and control of the risk of excessive intakes; (2) safety, quality control, and assurance considerations; (3) coordination between public health nutrition interventions and other interventions and sectors; and (4) the legislative framework and policy coherence needed for simultaneous nutrition interventions. This paper provides the background and rationale of the technical consultation, synopsizes the presentations, and provides a summary of the main considerations proposed by the working groups.


Assuntos
Minerais/administração & dosagem , Prática de Saúde Pública , Vitaminas/administração & dosagem , Humanos , Fatores de Risco
16.
Arch Med Res ; 49(6): 405-417, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30573199

RESUMO

BACKGROUND: Serum or plasma ferritin concentration is recommended by WHO as a biomarker to assess iron status in individuals and populations. METHODS: A systematic review was undertaken to summarise the evidence for ferritin reflecting iron status and to assess the cut-off points in different populations. Electronic databases were searched for studies evaluating ferritin concentrations compared against bone marrow aspirates for iron deficiency and to liver biopsies for risk of iron overload. RESULTS: From 18822 records, 298 studies were assessed in full-text, including 72 studies on iron deficiency and 36 on iron overload in the quantitative analysis. All studies were observational. For iron deficiency, the mean ferritin concentration in healthy individuals was 15.1 µg/L (9 studies, 390 participants) when bone marrow iron content was 0, and 70.4 µg/L (3 studies, 151 participants) when bone marrow iron was 1+ or higher. In non-healthy populations, mean ferritin concentrations were 82.43 µg/L for iron depletion (38 studies, 1023 participants) and 381.61 µg/L for iron sufficiency (38 studies, 1549 participants) with wide variations depending on the pathology. For iron overload the results point out to a cut-off close to 500 µg/L although the data was very limited. CONCLUSION: Ferritin concentration is low in iron deficient individuals and high in iron-loaded individuals, regardless of confounding clinical conditions. Current WHO thresholds for healthy populations appear valid but the data is limited for different age groups or physiological conditions. For iron overload, ferritin concentration would only help in the presumptive diagnosis and guide the need for further assessment.


Assuntos
Anemia Ferropriva/diagnóstico , Ferritinas/sangue , Sobrecarga de Ferro/diagnóstico , Ferro/sangue , Adulto , Anemia Ferropriva/sangue , Biomarcadores/sangue , Feminino , Humanos , Sobrecarga de Ferro/sangue , Masculino , Estudos Observacionais como Assunto , Padrões de Referência
17.
Matern Child Nutr ; 14 Suppl 5: e12704, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30585705

RESUMO

Health promotion, screening, diagnosis, and disease prevention are essential services of quality routine antenatal care for pregnant adult and adolescent women. Supplementation programmes in pregnancy, generally implemented in the context of antenatal care services, have had less than optimal results in many countries, generally attributed to limited access, low coverage, and reduced adherence to the recommended regimens and counselling. The World Health Organization Department of Nutrition for Health and Development, in collaboration with the United Nations Children's Fund and Nutrition International, convened the technical consultation "Multiple micronutrient supplements in pregnancy: Implementation considerations for successful incorporation into existing programmes." The objectives of the technical consultation were to (a) examine implementation experiences of micronutrient supplementation interventions in pregnant women, lessons learnt, and best practices; (b) discuss programmatic and technical considerations of interventions on multiple micronutrient supplementation in pregnant women in low-, middle-, and high-income countries; and (c) identify implementation considerations that can be useful to scaling up efforts by national policymaker and their advisors considering multiple micronutrient supplementation in pregnant women as part of existing antenatal care programmes as well as other delivery platforms. The consultation was based on presentations of background papers, case studies, and plenary discussions. Country representatives were asked to discuss the context of micronutrient supplementation for their countries and share implementation challenges they faced. This paper provides the background and rationale of the technical consultation, synopsises the presentations, and provides a summary of the main considerations and conclusions reached during plenary discussions.


Assuntos
Suplementos Nutricionais , Micronutrientes , Cuidado Pré-Natal , África Subsaariana , Ásia , Feminino , Humanos , Nicarágua , Gravidez , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/normas , Qualidade da Assistência à Saúde
18.
Curr Geriatr Rep ; 7(2): 103-113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721404

RESUMO

PURPOSE OF REVIEW: This review broadly discusses the consequences of inadequate consumption, by deficit or excess, of selected micronutrients on the quality of life and morbidity during aging, specifically considering increases in life expectancy and the costs of care in the older persons. RECENT FINDINGS: A literature review of the periods 2012 to 2018, focusing on vitamins A, B12, and D, calcium, iron and folate, was completed as these micronutrients are found to significantly affect the aging process. Causation and application of these micronutrients to disorders related to aging are controversial and mixed. This review highlights research needs and controversial points on the role of these micronutrients. SUMMARY: Micronutrient deficiencies are a common and avoidable contributor to decreased quality of life and healthcare costs in the older persons. Further research is needed to determine adequate intakes and innovative uses, including appropriate thresholds for improved health outcomes for this population.

20.
Ann N Y Acad Sci ; 1390(1): 3-13, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27936288

RESUMO

Biofortification of staple crops has been proposed as a strategy to address micronutrient malnutrition, particularly with respect to insufficient intake of vitamin A, iron, zinc, and folate. The World Health Organization, in collaboration with the Food and Agriculture Organization of the United Nations and the Sackler Institute for Nutrition Science at the New York Academy of Sciences, convened a technical consultation entitled "Staple Crops Biofortified with Vitamins and Minerals: Considerations for a Public Health Strategy" in April 2016. Participants of the consultation reviewed the definition of biofortification of staple crops, patterns of crops production, processing, consumption, seed varieties, and micronutrient stability and bioavailability, as well as farmers' adoption and acceptability of the modified crops. Also discussed were economic, environmental, safety, and equity aspects of biofortified crops, as well as legal, policy, regulatory, and ethical issues for the implementation of biofortification strategies in agriculture and nutrition. Consultation working groups identified important and emerging technical issues, lessons learned, and research priorities to better support the evidence of improved nutrition and unintended adverse effects of biofortification. This paper provides the background and rationale of the technical consultation, synopsizes the presentations, and provides a summary of the main considerations proposed by the working groups.


Assuntos
Produtos Agrícolas/química , Alimentos Fortificados , Micronutrientes , Saúde Pública , Agricultura , Disponibilidade Biológica , Inocuidade dos Alimentos , Humanos , Nigéria , Uganda , Nações Unidas , Vitaminas , Populações Vulneráveis , Organização Mundial da Saúde , Zâmbia
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