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2.
Adv Nutr ; 11(2): 185-199, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31566677

RESUMO

An ongoing challenge to our ability to address the role of food and nutrition in health promotion and disease prevention is how to design and implement context-specific interventions and guidance that are safe, efficacious, and avoid unintended consequences. The integration to effective implementation (I-to-I) concept is intended to address the complexities of the global health context through engagement of the continuum of stakeholders involved in the generation, translation, and implementation of evidence to public health guidance/programs. The I-to-I approach was developed under the auspices of the Micronutrient Forum and has been previously applied to the question of safety and effectiveness of interventions to prevent and treat nutritional iron deficiency. The present article applies the I-to-I approach to questions regarding the safety and utility of large-dose vitamin A supplementation programs, and presents the authors' perspective on key aspects of the topic, including coverage of the basic and applied biology of vitamin A nutrition and assessment, clinical implications, and an overview of the extant data with regard to both the justification for and utility of available intervention strategies. The article includes some practical considerations based on specific country experiences regarding the challenges of implementing vitamin A-related programs. This is followed by an overview of some challenges associated with engagement of the enabling communities that play a critical role in the implementation of these types of public health interventions. The article concludes with suggestions for potential approaches to move this important agenda forward.


Assuntos
Suplementos Nutricionais , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Criança , Pré-Escolar , Suplementos Nutricionais/efeitos adversos , Feminino , Saúde Global , Implementação de Plano de Saúde , Promoção da Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Avaliação Nutricional , Fenômenos Fisiológicos da Nutrição , Ciências da Nutrição , Estado Nutricional , Saúde Pública/métodos , Vitamina A/efeitos adversos , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/mortalidade
3.
Arch Dis Child ; 104(3): 217-226, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30425075

RESUMO

BACKGROUND: Biannual vitamin A supplementation is a well-established survival tool for preschool children 6 months and older in vitamin A deficient populations but this schedule misses the opportunity to intervene on most young infant deaths. Randomised trials of neonatal vitamin A supplementation (NVAS) in the first few days of life to assess its impact on under 6-month mortality in low/middle-income countries have had varying results. METHODS: Investigators of 11 published randomised placebo-controlled NVAS trials (n=163 567 children) reanalysed their data according to an agreed plan and pooled the primary outcomes of mortality from supplementation through 6 and 12 months of age using random effects models and meta-regression. One investigator withdrew but allowed use of the data. FINDINGS: Overall there was no effect of NVAS on infant survival through 6 (risk ratio (RR) 0.97; 95% CI 0.89 to 1.06) or 12 months of age (RR 1.00; 95% CI 0.93 to 1.08) but results varied by study population characteristics.NVAS significantly reduced 6-month mortality among the trials conducted in Southern Asia (RR 0.87; 95% CI 0.77 to 0.98), in contexts with moderate or severe vitamin A deficiency (defined as 10% or higher proportion of women with serum retinol <0.7 µmol/L or 5% or more women with night blindness) (RR 0.87; 95% CI 0.80 to 0.94), early infant mortality was 30 or more per 1000 live births (RR 0.91; 95% CI 0.85 to 0.98), 75% or more of infant mortality occurred in the first 6 months of life (RR 0.92; 95% CI 0.84 to 1.01), or where >32% mothers had no schooling (RR 0.88; 95% CI 0.80 to 0.96). NVAS did not reduce mortality in the first 6 months of life in trials conducted in Africa, in contexts characterised by a low prevalence of vitamin A deficiency, lower rates of infant mortality and where maternal education was more prevalent. There was a suggestion of increased infant mortality in trials conducted in Africa (RR 1.07; 95% CI 1.00 to 1.15).Individual-level characteristics such as sex, birth weight, gestational age and size, age at dosing, parity, time of breast feeding initiation, maternal education and maternal vitamin A supplementation did not modify the impact of NVAS. CONCLUSION: NVAS reduced infant mortality in South Asia, in contexts where the prevalence of maternal vitamin A deficiency is moderate to severe and early infant mortality is high; but it had no beneficial effect on infant survival in Africa, in contexts where the prevalence of maternal vitamin A deficiency is lower, early infant mortality is low.


Assuntos
Deficiência de Vitamina A/terapia , Vitamina A/administração & dosagem , Vitaminas/administração & dosagem , Suplementos Nutricionais , Escolaridade , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Masculino , Mães/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Distribuição por Sexo , Deficiência de Vitamina A/mortalidade
4.
J Nutr ; 147(11): 2194S-2203S, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28904117

RESUMO

Background: We previously compared the potential effects of different intervention strategies for achieving dietary vitamin A (VA) adequacy. The Lives Saved Tool (LiST) permits estimates of lives saved through VA interventions but currently only considers periodic VA supplements (VASs).Objective: We aimed to adapt the LiST method for estimating the mortality impact of VASs to estimate the impact of other VA interventions (e.g., food fortification) on child mortality and to estimate the number of lives saved by VA interventions in 3 macroregions in Cameroon.Methods: We used national dietary intake data to predict the effects of VA intervention programs on the adequacy of VA intake. LiST parameters of population affected fraction and intervention coverage were replaced with estimates of prevalence of inadequate intake and effective coverage (proportion achieving adequate VA intake). We used a model of liver VA stores to derive an estimate of the mortality reduction from achieving dietary VA adequacy; this estimate and a conservative assumption of equivalent mortality reduction for VAS and VA intake were applied to projections for Cameroon.Results: There were 2217-3048 total estimated VA-preventable deaths in year 1, with 58% occurring in the North macroregion. The relation between effective coverage and lives saved differed by year and macroregion due to differences in total deaths, diarrhea burden, and prevalence of low VA intake. Estimates of lives saved by VASs (the intervention common to both methods) were similar with the use of the adapted method (in 2012: North, 743-1021; South, 280-385; Yaoundé and Douala, 146-202) and the "usual" LiST method (North: 697; South: 381; Yaoundé and Douala: 147).Conclusions: Linking effective coverage estimates with an adapted LiST method permits estimation of the effects of combinations of VA programs (beyond VASs only) on child mortality to aid program planning and management. Rigorous program monitoring and evaluation are necessary to confirm predicted impacts.


Assuntos
Alimentos Fortificados , Micronutrientes/administração & dosagem , Deficiência de Vitamina A/dietoterapia , Deficiência de Vitamina A/mortalidade , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Camarões/epidemiologia , Criança , Mortalidade da Criança , Pré-Escolar , Dieta , Suplementos Nutricionais , Humanos , Lactente , Micronutrientes/deficiência , Modelos Teóricos , Prevalência , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Food Nutr Bull ; 38(2): 260-266, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28513263

RESUMO

BACKGROUND: Although vitamin A supplementation reduces child mortality, it remains unclear whether dosing frequency, total dose, or duration modifies effectiveness. OBJECTIVE: Determine whether mortality effects of vitamin A vary by dosing frequency, total dose, or duration. METHODS: Meta-analysis of randomized controlled trials, identified by systematic review and expert opinion, utilizing relatively standard World Health Organization doses in children <5 years. Meta-regression evaluated whether mortality effects varied by dosing frequency, total dose, or supplementation duration. RESULTS: Identified 17 trials, including 1,180,718 children, mean (standard deviation [SD]) age 31.5 (15.4) months at baseline. Supplementation frequency ranged every 3 months-every 2 years, supplementation duration 4-60 months (mean = 15.4; SD = 12.8), and total dose 134,361-2,200,000 IU (mean = 667,132 IU; SD = 540,795). Compared with control, vitamin A reduced mortality 22% (95% confidence interval [CI] = 10-32; P = 0.002). This protective effect was not modified by increasing supplementation frequency (dose/year: relative risk [RR] = 1.02; 95% CI = 0.98-1.06; P = .22), total dose (per 200,000 IU: RR = 1.02; 95% CI = 0.97-1.06; P = .31), nor supplementation duration (per year: RR = 1.06; 95% CI = 0.97-1.15; P = 0.14). Multivariate meta-regression showed similar results. Sensitivity analyses excluding 1 controversial trial (Aswathi 2013) did not alter findings. CONCLUSION: Results confirm benefits of vitamin A supplementation in children <5 years in nations with vitamin A deficiency, without influence of frequency, total dose, or dosing duration within ranges evaluated. These findings inform design and efficiency of vitamin A supplementation policies.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Suplementos Nutricionais , Medicina Baseada em Evidências , Saúde Global , Deficiência de Vitamina A/dietoterapia , Vitamina A/uso terapêutico , Mortalidade da Criança , Pré-Escolar , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Vitamina A/administração & dosagem , Deficiência de Vitamina A/mortalidade , Deficiência de Vitamina A/prevenção & controle
6.
Cochrane Database Syst Rev ; 3: CD008524, 2017 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-28282701

RESUMO

BACKGROUND: Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation for children aged 6 to 59 months. There are new data available from recently published randomised trials since the previous publication of this review in 2010, and this update incorporates this information and reviews the evidence. OBJECTIVES: To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years. SEARCH METHODS: In March 2016 we searched CENTRAL, Ovid MEDLINE, Embase, six other databases, and two trials registers. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation. DATA COLLECTION AND ANALYSIS: For this update, two reviewers independently assessed studies for inclusion and abstracted data, resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence. MAIN RESULTS: We identified 47 studies (4 of which are new to this review), involving approximately 1,223,856 children. Studies took place in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most of the studies included equal numbers of girls and boys and lasted about a year. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for vitamin A compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-quality evidence). This result was sensitive to choice of model, and a random-effects meta-analysis showed a different summary estimate (24% reduction: RR 0.76, 95% CI 0.66 to 0.88); however, the confidence intervals overlapped with that of the fixed-effect model. Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 participants; high-quality evidence). There was no significant effect for VAS on mortality due to measles, respiratory disease, and meningitis. VAS reduced incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies; 77,946 participants; low-quality evidence) and measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies; 19,566 participants; moderate-quality evidence). However, there was no significant effect on incidence of respiratory disease or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies; 10,541 participants; moderate-quality evidence). AUTHORS' CONCLUSIONS: Vitamin A supplementation is associated with a clinically meaningful reduction in morbidity and mortality in children. Therefore, we suggest maintaining the policy of universal supplementation for children under five years of age in populations at risk of VAD. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented vitamin A deficiency, it would be unethical to conduct placebo-controlled trials.


Assuntos
Deficiência de Vitamina A/tratamento farmacológico , Vitamina A/administração & dosagem , Vitaminas/administração & dosagem , Causas de Morte , Pré-Escolar , Diarreia/mortalidade , Humanos , Lactente , Sarampo/mortalidade , Meningite/mortalidade , Cegueira Noturna/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos Respiratórios/mortalidade , Infecções Respiratórias/mortalidade , Vitamina A/efeitos adversos , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/mortalidade , Vitaminas/efeitos adversos , Vômito/epidemiologia
7.
Nutrients ; 9(3)2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28294986

RESUMO

It is usually acknowledged that high-dose vitamin A supplementation (VAS) provides no sustained improvement in vitamin A status, and that the effect of VAS on mortality is more likely linked to its immunomodulating effects. Nonetheless, it is widely assumed that we can deduce something about the need for continuing or stopping VAS programs based on studies of the biochemical prevalence of vitamin A deficiency (VAD). This is no longer a tenable assumption. The justification for using VAS is to reduce child mortality, but there is now doubt that VAS has any effect on overall child mortality. What we need now are not surveys of VAD, but proper randomized trials to evaluate whether VAS has beneficial effects on overall child survival.


Assuntos
Mortalidade da Criança , Suplementos Nutricionais , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Criança , Humanos , Vitamina A/sangue , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/mortalidade
8.
Arch Dis Child ; 102(3): 216-223, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27471856

RESUMO

BACKGROUND: Despite evidence for the benefits of vitamin A supplementation (VAS) among children 6 to 59 months of age, the feasibility of introduction and potential benefit of VAS in the neonatal period in public health programmes is uncertain. OBJECTIVE: The primary objective was to evaluate the feasibility and effectiveness of early neonatal VAS (single dose of 50 000 international units within 48-72 hours after birth) delivered through the public sector Lady Health Worker (LHW) programme in rural Pakistan and to document its association with a reduction in mortality at 6 months of age. METHODS: A community-based, cluster randomised, placebo-controlled trial was undertaken in two districts of rural Pakistan. LHWs dispensed vitamin A/placebo in identical capsules to newborn infants within 48-72 hours of birth. Follow-up visits were undertaken at 1 week of age and every 4 weeks thereafter until 6 months of age. RESULTS: Of a total of 15 433 consecutive pregnancies among eligible women of reproductive age, 13 225 pregnancies were registered, 12 218 live births identified and 11 028 newborn infants reached by LHWs. Of these, 5380 (49%) received neonatal VAS and 5648 (51%) placebo. The LHWs successfully delivered the capsules to 79% of newborns within 72 hours of birth with no significant adverse effects. Although the proportion of days observed with symptoms of fever, diarrhoea or rapid breathing were lower with neonatal VAS, these differences were not statistically significant. Mortality rates in the two groups were comparable at 6 months of age. CONCLUSIONS: While our study demonstrated that neonatal VAS was safe and could be feasibly delivered by LHWs in Pakistan as part of their early postnatal visits, the overall lack of benefit on neonatal and 6-month morbidity and mortality in our population suggests the need for further evaluation of this intervention in populations at risk. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT00674089.


Assuntos
Suplementos Nutricionais , Deficiência de Vitamina A/dietoterapia , Vitamina A/administração & dosagem , Vitaminas/administração & dosagem , Adolescente , Adulto , Cápsulas , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Saúde da População Rural , Fatores Socioeconômicos , Vitamina A/sangue , Deficiência de Vitamina A/mortalidade , Adulto Jovem
9.
Lancet Glob Health ; 3(9): e528-36, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26275329

RESUMO

BACKGROUND: Vitamin A deficiency is a risk factor for blindness and for mortality from measles and diarrhoea in children aged 6-59 months. We aimed to estimate trends in the prevalence of vitamin A deficiency between 1991 and 2013 and its mortality burden in low-income and middle-income countries. METHODS: We collated 134 population-representative data sources from 83 countries with measured serum retinol concentration data. We used a Bayesian hierarchical model to estimate the prevalence of vitamin A deficiency, defined as a serum retinol concentration lower than 0·70 µmol/L. We estimated the relative risks (RRs) for the effects of vitamin A deficiency on mortality from measles and diarrhoea by pooling effect sizes from randomised trials of vitamin A supplementation. We used information about prevalences of deficiency, RRs, and number of cause-specific child deaths to estimate deaths attributable to vitamin A deficiency. All analyses included a systematic quantification of uncertainty. FINDINGS: In 1991, 39% (95% credible interval 27-52) of children aged 6-59 months in low-income and middle-income countries were vitamin A deficient. In 2013, the prevalence of deficiency was 29% (17-42; posterior probability [PP] of being a true decline=0·81). Vitamin A deficiency significantly declined in east and southeast Asia and Oceania from 42% (19-70) to 6% (1-16; PP>0·99); a decline in Latin America and the Caribbean from 21% (11-33) to 11% (4-23; PP=0·89) also occurred. In 2013, the prevalence of deficiency was highest in sub-Saharan Africa (48%; 25-75) and south Asia (44%; 13-79). 94 500 (54 200-146 800) deaths from diarrhoea and 11 200 (4300-20 500) deaths from measles were attributable to vitamin A deficiency in 2013, which accounted for 1·7% (1·0-2·6) of all deaths in children younger than 5 years in low-income and middle-income countries. More than 95% of these deaths occurred in sub-Saharan Africa and south Asia. INTERPRETATION: Vitamin A deficiency remains prevalent in south Asia and sub-Saharan Africa. Deaths attributable to this deficiency have decreased over time worldwide, and have been almost eliminated in regions other than south Asia and sub-Saharan Africa. This new evidence for both prevalence and absolute burden of vitamin A deficiency should be used to reconsider, and possibly revise, the list of priority countries for high-dose vitamin A supplementation such that a country's priority status takes into account both the prevalence of deficiency and the expected mortality benefits of supplementation. FUNDIN: Bill & Melinda Gates Foundation, Grand Challenges Canada, UK Medical Research Council.


Assuntos
Mortalidade da Criança/tendências , Países em Desenvolvimento/estatística & dados numéricos , Deficiência de Vitamina A/epidemiologia , Teorema de Bayes , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Prevalência , Deficiência de Vitamina A/mortalidade
10.
Trans R Soc Trop Med Hyg ; 109(1): 36-45, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25477326

RESUMO

WHO recommends high-dose vitamin A supplementation (VAS) to children from 6 months to 5 years of age in low-income countries, in order to prevent and treat vitamin A deficiency-associated morbidity and mortality. The current policy does not discriminate this recommendation either by sex or vaccination status of the child. There is accumulating evidence that the effects of VAS on morbidity, mortality and immunological parameters depend on concomitant vaccination status. Moreover, these interactions may manifest differently in males and females. Certain vaccines administered through the Expanded Program on Immunization have been shown to alter all-cause mortality from infections other than the vaccine-targeted disease. This review summarizes the evidence from observational studies and randomized-controlled trials of the effects of VAS on these so-called heterologous or non-specific effects of vaccines, with a focus on sex differences. In general, VAS seems to enhance the heterologous effects of vaccines, particularly for diphtheria-tetanus-pertussis and live measles vaccines, where some studies, although not unanimously, show a stronger interaction between VAS and vaccination in females. We suggest that vaccination status and sex should be considered when evaluating the effects of VAS in early life.


Assuntos
Imunidade Heteróloga/efeitos dos fármacos , Imunização , Deficiência de Vitamina A/imunologia , Vitamina A/administração & dosagem , Vacina BCG , Criança , Pré-Escolar , Países em Desenvolvimento , Suplementos Nutricionais , Vacina contra Difteria, Tétano e Coqueluche , Feminino , Disparidades nos Níveis de Saúde , Humanos , Imunidade Heteróloga/imunologia , Imunização/métodos , Lactente , Masculino , Vacina contra Sarampo , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores Sexuais , Vitamina A/efeitos adversos , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/mortalidade
11.
Lancet ; 385(9975): 1324-32, 2015 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-25499543

RESUMO

BACKGROUND: Supplementation of vitamin A in children aged 6-59 months improves child survival and is implemented as global policy. Studies of the efficacy of supplementation of infants in the neonatal period have inconsistent results. We aimed to assess the efficacy of oral supplementation with vitamin A given to infants in the first 3 days of life to reduce mortality between supplementation and 180 days (6 months). METHODS: We did an individually randomised, double-blind, placebo-controlled trial of infants born in the Morogoro and Dar es Salaam regions of Tanzania. Women were identified during antenatal clinic visits or in the labour wards of public health facilities in Dar es Salaam. In Kilombero, Ulanga, and Kilosa districts, women were seen at home as part of the health and demographic surveillance system. Newborn infants were eligible for randomisation if they were able to feed orally and if the family intended to stay in the study area for at least 6 months. We randomly assigned infants to receive one dose of 50,000 IU of vitamin A or placebo in the first 3 days after birth. Infants were randomly assigned in blocks of 20, and investigators, participants' families, and data analysis teams were masked to treatment assignment. We assessed infants on day 1 and day 3 after dosing, as well as at 1, 3, 6, and 12 months after birth. The primary endpoint was mortality at 6 months, assessed by field interviews. The primary analysis included only children who were not lost to follow-up. This trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), number ACTRN12610000636055. FINDINGS: Between Aug 26, 2010, and March 3, 2013, 31,999 newborn babies were randomly assigned to receive vitamin A (n=15,995) or placebo (n=16,004; 15,428 and 15,464 included in analysis of mortality at 6 months, respectively). We did not find any evidence for a beneficial effect of vitamin A supplementation on mortality in infants at 6 months (26 deaths per 1000 livebirths in vitamin A vs 24 deaths per 1000 livebirths in placebo group; risk ratio 1·10, 95% CI 0·95-1·26; p=0·193). There was no evidence of a differential effect for vitamin A supplementation on mortality by sex; risk ratio for mortality at 6 months for boys was 1·08 (0·90-1·29) and for girls was 1·12 (0·91-1·39). There was also no evidence of adverse effects of supplementation within 3 days of dosing. INTERPRETATION: Neonatal vitamin A supplementation did not result in any immediate adverse events, but had no beneficial effect on survival in infants in Tanzania. These results strengthen the evidence against a global policy recommendation for neonatal vitamin A supplementation. FUNDING: Bill & Melinda Gates Foundation to WHO.


Assuntos
Deficiência de Vitamina A/tratamento farmacológico , Vitamina A/análogos & derivados , Vitaminas/administração & dosagem , Administração Oral , Cápsulas , Suplementos Nutricionais , Diterpenos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Ésteres de Retinil , Tanzânia/epidemiologia , Resultado do Tratamento , Vitamina A/administração & dosagem , Deficiência de Vitamina A/mortalidade , Vitamina E/administração & dosagem
12.
Lancet ; 385(9975): 1333-42, 2015 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-25499546

RESUMO

BACKGROUND: Vitamin A supplementation in children aged 6 months to 5 years has been shown to reduce mortality. The efficacy of neonatal supplementation with vitamin A to reduce mortality in the first 6 months of life is plausible but not established. We aimed to assess the efficacy of neonatal oral supplementation with vitamin A to reduce mortality between supplementation and 6 months of age. METHODS: We undertook an individually randomised, double-blind, placebo-controlled trial in Haryana, India. We identified pregnant women through a surveillance programme undertaken every 3 months of all female residents in two districts of Haryana, India, aged 15-49 years, and screened every identified livebirth. Eligible participants were neonates whose parents consented to participate, were likely to stay in the study area until at least 6 months of age, and were able to feed orally at the time of enrolment. Participants were randomly assigned to receive oral capsules containing vitamin A (retinol palmitate 50,000 IU plus vitamin E 9·5-12·6 IU) or placebo (vitamin E 9·5-12·6 IU) within 72 h of birth. Randomisation was in blocks of 20 according to a randomisation list prepared by a statistician not otherwise involved with the trial. Investigators, participants' families, and the data analysis team were masked to treatment allocation. The primary outcome was mortality between supplementation and 6 months of age. Analysis included all participants assigned to study groups. This trial is registered with ClinicalTrials.gov, number NCT01138449, and the Indian Council of Medical Research Clinical Trial Registry, number CTRI/2010/091/000220. FINDINGS: Between June 24, 2010, and July 1, 2012 we screened 47,777 neonates and randomly assigned 44,984 to receive vitamin A (22,493) or placebo (22,491). Between supplementation and 6 months of age, 656 infants died in the vitamin A group compared with 726 in the placebo group (29·2 per 1000 vs 32·3 per 1000; difference -3·1 per 1000, 95% CI -6·3 to 0·1; risk ratio 0·90, 95% CI 0·81 to 1·00). We noted no significant interactions between the intervention effect and sex on mortality at 6 months (p=0·409). Supplementation with 50,000 IU vitamin A within the first 72 h of life was generally safe and well tolerated, with the exception of a small excess risk of transient bulging fontanelle (205 cases in the vitamin A group confirmed by physician vs 80 cases in the placebo group, risk ratio 2·56 [95% CI 1·98-3·32]). INTERPRETATION: The findings of this study, done in a population in which vitamin A deficiency is a moderate public health problem, are consistent with a modest reduction in mortality between supplementation and 6 months of age. These findings must be viewed together with similar trials in other populations to enable determination of appropriate public health policy. FUNDING: Bill & Melinda Gates Foundation to WHO.


Assuntos
Deficiência de Vitamina A/tratamento farmacológico , Vitamina A/análogos & derivados , Vitaminas/administração & dosagem , Administração Oral , Cápsulas , Suplementos Nutricionais , Diterpenos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Índia/epidemiologia , Lactente , Mortalidade Infantil , Recém-Nascido , Masculino , Ésteres de Retinil , Resultado do Tratamento , Vitamina A/administração & dosagem , Deficiência de Vitamina A/mortalidade , Vitamina E/administração & dosagem
13.
Lancet ; 385(9975): 1315-23, 2015 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-25499545

RESUMO

BACKGROUND: Results of randomised controlled trials of newborn (age 1-3 days) vitamin A supplementation have been inconclusive. The WHO is coordinating three large randomised trials in Ghana, India, and Tanzania (Neovita trials). We present the findings of the Neovita trial in Ghana. METHODS: This study was a population-based, individually randomised, double-blind, placebo-controlled trial in the Brong Ahafo region of Ghana. The trial participants were infants aged at least 2 h, identified at home or facilities on the day of birth or in the next 2 days, able to feed orally, and likely to stay in the study area for at least 6 months. They were randomly assigned (ratio 1:1) to receive either one oral dose of vitamin A (50,000 IU) or placebo immediately after recruitment. The research team and parents of the infants were masked to treatment assignment. Follow-up home visits were undertaken every 4 weeks, when data were recorded for deaths, facility use, and care seeking. The primary outcome was post-supplementation mortality to 6 months of age. Analysis was by intention to treat. Potential adverse events were recorded at 1 and 3 days after supplementation. This trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR)CTRN12610000582055. FINDINGS: We assessed 26,414 livebirths for eligibility between Aug 16, 2010, and Nov 7, 2011. We recruited 22,955 newborn infants, with 11,474 randomly assigned to receive vitamin A and 11,481 to receive placebo. Loss to follow-up was low with vital status at 6 months of age reported for 22,698 (98·9%) infants. We recorded 278 post-supplementation deaths to 6 months of age in the vitamin A group (mortality risk 24·5 in 1000 supplemented infants) and 248 deaths in the placebo group (mortality risk 21·8 per 1000 supplemented infants), relative risk (RR) 1·12 (95% CI 0·95-1·33; p=0·183) and risk difference (RD) 2·66 (95% CI -1·25 to 6·57; p=0·18). Adverse events within 3 days of supplementation did not differ by trial group. 122 infants died in the first 3 days after supplementation; 70 (0·6%) in the vitamin A and 52 (0·5%) in the placebo group (risk ratio [RR] 1·35, 95% CI 0·94-1·93, p=0·102). 53 infants were reported to have a bulging fontanelle; 32 (0·3%) in the vitamin A group and 21 (0·2%) in the placebo group (RR 1·53, 0·88-2·62, p=0·130). INTERPRETATION: The results of this trial do not support inclusion of newborn vitamin A supplementation as a child survival strategy in Ghana. FUNDING: Bill & Melinda Gates Foundation grant to the WHO.


Assuntos
Deficiência de Vitamina A/tratamento farmacológico , Vitamina A/análogos & derivados , Vitaminas/administração & dosagem , Administração Oral , Suplementos Nutricionais , Diterpenos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Gana/epidemiologia , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Ésteres de Retinil , Resultado do Tratamento , Vitamina A/administração & dosagem , Deficiência de Vitamina A/mortalidade , Vitamina E
15.
Food Nutr Bull ; 35(2): 203-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25076768

RESUMO

BACKGROUND: Preventive vitamin A supplementation (VAS) is an essential child survival intervention. In India, VAS program coverage has remained relatively low, with wide interstate variation. OBJECTIVE: To review the VAS program in India, particularly in Bihar and Odisha, the two states that have had the most successful VAS programs, to define best practices and identify critical success factors. METHODS: A thorough review of existing relevant literature was carried out, supplemented by field visits and interviews with selected partners. RESULTS: Both states have adopted a biannual approach to reach out to children 1 to 5 years of age with VAS every 6 months, while infants below 1 year of age receive their first VAS dose with the measles immunization at 9 months. The critical success factors for the VAS program in the two states include strong leadership and ownership by the state government; close coordination between the two departments that are involved in the VAS program; effective microplanning prior to each biannual round; flexible dosing mechanisms that enhance coverage in hard-to-reach areas; a stable procurement and distribution mechanism to ensure an adequate, timely, and sustainable supply of VAS; intensive social mobilization and communication; and appropriate training and supervision of staff. CONCLUSIONS: The governments of Bihar and Odisha have demonstrated that it is feasible to implement a successful and inclusive VAS program in India. The challenge now is to reach out to the remaining 30% to 40% of children who are undoubtedly the hardest to reach and potentially the most vulnerable.


Assuntos
Programas Governamentais , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Pré-Escolar , Suplementos Nutricionais , Programas Governamentais/história , Programas Governamentais/organização & administração , História do Século XX , História do Século XXI , Humanos , Índia , Lactente , Deficiência de Vitamina A/mortalidade
16.
Int J Vitam Nutr Res ; 84(1-2): 65-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25835237

RESUMO

PURPOSE: Vitamin A deficiency is among major health problems worldwide that leads to blindness, retarded growth and death, particularly in developing countries. In these countries, vitamin A deficiency largely affects pre-school children, pregnant and lactating mothers, and the rural poor. For instance, the predicted prevalence of vitamin A deficiency for 36 sub-Saharan African countries is 19.1%. METHODS: Different strategies, including vitamin A supplementation, food fortification and dietary diversification, have been used to combat this problem. However, these strategies are not sustainable due to their high costs. RESULTS: Orange-fleshed sweet potato (Ipomoea batatas L. Lam) is a low priced crop, which is part of staple foods in most of sub-Saharan Africa that can be a year-round source of vitamin A. Most of the orange-fleshed sweet potato varieties contain 3000-16000 µg 100 g(-1) of ß-carotene and this contributes to 250 to 1300 µg 100 g(-1) Retinol Activity Equivalents (RAE). Therefore, by using orange-fleshed sweet potato, it is possible to improve vitamin A status, increase the bio-availability of different micro-nutrients such as Fe, Zn, Ca and Mg, reduce vitamin A deficiency and hence reduce child mortality rates by 23 to 30%. CONCLUSION: The article highlights the significance of vitamin A for human nutrition, the effect of vitamin A deficiency, the different prevention methods and the potential of orange- fleshed sweet potato as a food crop to prevent vitamin A deficiency.


Assuntos
Dieta , Ipomoea batatas , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , África/epidemiologia , Mortalidade da Criança , Pré-Escolar , Suplementos Nutricionais , Feminino , Alimentos Fortificados , Nível de Saúde , Humanos , Alimentos Infantis , Lactação , Necessidades Nutricionais , Estado Nutricional , Tubérculos/química , Pobreza , Gravidez , População Rural , Vitamina A/fisiologia , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/mortalidade , beta Caroteno/administração & dosagem , beta Caroteno/análise
17.
Lancet ; 381(9876): 1469-77, 2013 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-23498849

RESUMO

BACKGROUND: In north India, vitamin A deficiency (retinol <0·70 µmol/L) is common in pre-school children and 2-3% die at ages 1·0-6·0 years. We aimed to assess whether periodic vitamin A supplementation could reduce this mortality. METHODS: Participants in this cluster-randomised trial were pre-school children in the defined catchment areas of 8338 state-staffed village child-care centres (under-5 population 1 million) in 72 administrative blocks. Groups of four neighbouring blocks (clusters) were cluster-randomly allocated in Oxford, UK, between 6-monthly vitamin A (retinol capsule of 200,000 IU retinyl acetate in oil, to be cut and dripped into the child's mouth every 6 months), albendazole (400 mg tablet every 6 months), both, or neither (open control). Analyses of retinol effects are by block (36 vs 36 clusters). The study spanned 5 calendar years, with 11 6-monthly mass-treatment days for all children then aged 6-72 months. Annually, one centre per block was randomly selected and visited by a study team 1-5 months after any trial vitamin A to sample blood (for retinol assay, technically reliable only after mid-study), examine eyes, and interview caregivers. Separately, all 8338 centres were visited every 6 months to monitor pre-school deaths (100,000 visits, 25,000 deaths at ages 1·0-6·0 years [the primary outcome]). This trial is registered at ClinicalTrials.gov, NCT00222547. FINDINGS: Estimated compliance with 6-monthly retinol supplements was 86%. Among 2581 versus 2584 children surveyed during the second half of the study, mean plasma retinol was one-sixth higher (0·72 [SE 0·01] vs 0·62 [0·01] µmol/L, increase 0·10 [SE 0·01] µmol/L) and the prevalence of severe deficiency was halved (retinol <0·35 µmol/L 6%vs 13%, decrease 7% [SE 1%]), as was that of Bitot's spots (1·4%vs 3·5%, decrease 2·1% [SE 0·7%]). Comparing the 36 retinol-allocated versus 36 control blocks in analyses of the primary outcome, deaths per child-care centre at ages 1·0-6·0 years during the 5-year study were 3·01 retinol versus 3·15 control (absolute reduction 0·14 [SE 0·11], mortality ratio 0·96, 95% CI 0·89-1·03, p=0·22), suggesting absolute risks of death between ages 1·0 and 6·0 years of approximately 2·5% retinol versus 2·6% control. No specific cause of death was significantly affected. INTERPRETATION: DEVTA contradicts the expectation from other trials that vitamin A supplementation would reduce child mortality by 20-30%, but cannot rule out some more modest effect. Meta-analysis of DEVTA plus eight previous randomised trials of supplementation (in various different populations) yielded a weighted average mortality reduction of 11% (95% CI 5-16, p=0·00015), reliably contradicting the hypothesis of no effect. FUNDING: UK Medical Research Council, USAID, World Bank (vitamin A donated by Roche).


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Suplementos Nutricionais , Deficiência de Vitamina A/prevenção & controle , Vitamina A/análogos & derivados , Adjuvantes Imunológicos/sangue , Albendazol/administração & dosagem , Antiprotozoários/administração & dosagem , Criança , Mortalidade da Criança/tendências , Pré-Escolar , Análise por Conglomerados , Diterpenos , Feminino , Seguimentos , Humanos , Índia/epidemiologia , Lactente , Masculino , Ésteres de Retinil , Saúde da População Rural , Resultado do Tratamento , Vitamina A/administração & dosagem , Vitamina A/sangue , Deficiência de Vitamina A/mortalidade
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