Vitamin A supplementation for reducing the risk of mother-to-child transmission of HIV infection

The Effect of Vitamin A on Clinical Manifestations of Recurrent Pyelonephritis in Children

Background: Pyelonephritis as a life-threatening infection often leads to renal scarring, which presumably controls by minerals. Objectives: The aim of this study was pyelonephritis treatment by vitamin A in children. Methods: In the current study,106 cases from Imam Reza pediatric clinic and Amir-Kabir Hospital, considered a study group. Children divided into groups with or without urinary incontinence. Demographic data, clinical manifestations, and urinary biomarkers were evaluated and then statistically analyzed. Results: Our data showed that there is a statistical difference between study groups in terms of dysuria (P = 0.001), abdominal pain (P = 0.001), frequency (P = 0.003), incontinency (P = 0.001), urgency (P = 0.002), intermittency (P = 0.004) and fever (P = 0.002). Conclusions: It has been assumed that vitamin A as a therapeutic agent could be used in children with vesicoureteral reflux induced by Pyelonephritis and congenital anomalies.

Vitamin A supplements for reducing mother-to-child HIV transmission

BACKGROUND

Strategies to reduce the risk of mother-to-child transmission of the human immunodeficiency virus (HIV) include lifelong antiretroviral therapy (ART) for HIV-positive women, exclusive breastfeeding from birth for six weeks plus nevirapine or replacement feeding plus nevirapine from birth for four to six weeks, elective Caesarean section delivery, and avoiding giving children chewed food. In some settings, these interventions may not be practical, feasible, or affordable. Simple, inexpensive, and effective interventions (that could potentially be implemented even in the absence of prenatal HIV testing programmes) would be valuable. Vitamin A, which plays a role in immune function, is one low-cost intervention that has been suggested in such settings.

OBJECTIVES

To summarize the effects of giving vitamin A supplements to HIV-positive women during pregnancy and after delivery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) up to 25 August 2017, and checked the reference lists of relevant articles for eligible studies.

SELECTION CRITERIA

We included randomized controlled trials conducted in any setting that compared vitamin A supplements to placebo or no intervention among HIV-positive women during pregnancy or after delivery, or both.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed study eligibility and extracted data. We expressed study results as risk ratios (RR) or mean differences (MD) as appropriate, with their 95% confidence intervals (CI), and conducted random-effects meta-analyses. This is an update of a review last published in 2011.

MAIN RESULTS

Five trials met the inclusion criteria. These were conducted in Malawi, South Africa, Tanzania, and Zimbabwe between 1995 and 2005 and none of the participants received ART. Women allocated to intervention arms received vitamin A supplements at a variety of doses (daily during pregnancy; a single dose immediately after delivery, or daily doses during pregnancy plus a single dose after delivery). Women allocated to comparison arms received identical placebo (6601 women, 4 trials) or no intervention (697 women, 1 trial). Four trials (with 6995 women) had low risk of bias and one trial (with 303 women) had high risk of attrition bias.The trials show that giving vitamin A supplements to HIV-positive women during pregnancy, the immediate postpartum period, or both, probably has little or no effect on mother-to-child transmission of HIV (RR 1.07, 95% CI 0.91 to 1.26; 4428 women, 5 trials, moderate certainty evidence) and may have little or no effect on child death by two years of age (RR 1.06, 95% CI 0.92 to 1.22; 3883 women, 3 trials, low certainty evidence). However, giving vitamin A supplements during pregnancy may increase the mean birthweight (MD 34.12 g, 95% CI -12.79 to 81.02; 2181 women, 3 trials, low certainty evidence) and probably reduces the incidence of low birthweight (RR 0.78, 95% CI 0.63 to 0.97; 1819 women, 3 trials, moderate certainty evidence); but we do not know whether vitamin A supplements affect the risk of preterm delivery (1577 women, 2 trials), stillbirth (2335 women, 3 trials), or maternal death (1267 women, 2 trials).

AUTHORS' CONCLUSIONS

Antepartum or postpartum vitamin A supplementation, or both, probably has little or no effect on mother-to-child transmission of HIV in women living with HIV infection and not on antiretroviral drugs. The intervention has largely been superseded by ART which is widely available and effective in preventing vertical transmission.

Interventions for preventing mother-to-child HIV transmission: protocol of an overview of systematic reviews

INTRODUCTION

Various interventions to prevent mother-to-child-transmission (MTCT) of HIV have been investigated and implemented. A number of systematic reviews assessing the efficacy of interventions for the prevention of MTCT of HIV reported antiretroviral prophylaxis, caesarean section before labour and before ruptured membranes, and complete avoidance of breastfeeding were efficacious for preventing MTCT of HIV. Recent WHO guidelines recommend lifelong antiretroviral therapy for all pregnant women for treatment of the woman's own HIV infection and for prevention of MTCT of HIV. Therefore, the objective of this overview is to evaluate the currently available systematic reviews of interventions for preventing MTCT of HIV, and to identify the current best evidence-based interventions for reducing the risk of MTCT of HIV.

METHODS AND ANALYSIS

We will include only peer-reviewed systematic reviews of randomised or quasi-randomised controlled trials assessing the effects of interventions for preventing MTCT of HIV that target both HIV-infected women and children aged 2 years and younger born to HIV-infected women. We will search the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effectiveness, Ovid MEDLINE and EMBASE. We will assess review eligibility, the methodological quality of included systematic reviews using A Measurement Tool to Assess The Systematic Reviews and will extract data, comparing our results and resolving discrepancies by consensus. Finally, we will independently assess the certainty of the evidence using Grades of Recommendation, Assessment, Development and Evaluation.

ETHICS AND DISSEMINATION

Ethics approval is not required. We will publish the results in a peer-reviewed journal and present at conferences, which will inform future research and will be useful for healthcare managers, administrators and policymakers to guide resource allocation decisions and optimisation of interventions to prevent the MTCT of HIV.

Integration of HIV/AIDS services with maternal, neonatal and child health, nutrition, and family planning services

BACKGROUND

The integration of HIV/AIDS and maternal, neonatal, child health and nutrition services (MNCHN), including family planning (FP) is recognized as a key strategy to reduce maternal and child mortality and control the HIV/AIDS epidemic. However, limited evidence exists on the effectiveness of service integration.

OBJECTIVES

To evaluate the impact of integrating MNCHN-FP and HIV/AIDS services on health, behavioral, and economic outcomes and to identify research gaps.

SEARCH METHODS

Using the Cochrane Collaboration's validated search strategies for identifying reports of HIV interventions, along with appropriate keywords and MeSH terms, we searched a range of electronic databases, including the Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMBASE, MEDLINE (via PubMed), and Web of Science / Web of Social Science. The date range was from 01 January 1990 to 15 October 2010. There were no limits to language.

SELECTION CRITERIA

Included studies were published in peer-reviewed journals, and provided intervention evaluation data (pre-post or multi-arm study design).The interventions described were organizational strategies or change, process modifications or introductions of technologies aimed at integrating MNCHN-FP and HIV/AIDS service delivery.

DATA COLLECTION AND ANALYSIS

We identified 10,619 citations from the electronic database searches and 101 citations from hand searching, cross-reference searching and interpersonal communication. After initial screenings for relevance by pairs of authors working independently, a total of 121 full-text articles were obtained for closer examination.

MAIN RESULTS

Twenty peer-reviewed articles representing 19 interventions met inclusion criteria. There were no randomized controlled trials. One study utilized a stepped wedge design, while the rest were non-randomized trials, cohort studies, time series studies, cross-sectional studies, serial cross-sectional studies, and before-after studies. It was not possible to perform meta-analysis. Risk of bias was generally high. We found high between-study heterogeneity in terms of intervention types, study objectives, settings and designs, and reported outcomes. Most studies integrated FP with HIV testing (n=7) or HIV care and treatment (n=4). Overall, HIV and MNCHN-FP service integration was found to be feasible across a variety of integration models, settings and target populations. Nearly all studies reported positive post-integration effects on key outcomes including contraceptive use, antiretroviral therapy initiation in pregnancy, HIV testing, and quality of services.

AUTHORS' CONCLUSIONS

This systematic review's findings show that integrated HIV/AIDS and MNCHN-FP services are feasible to implement and show promise towards improving a variety of health and behavioral outcomes. However, significant evidence gaps remain. Rigorous research comparing outcomes of integrated with non-integrated services, including cost, cost-effectiveness, and health outcomes such as HIV and STI incidence, morbidity and mortality are greatly needed to inform programs and policy.

Living with uncertainty

The persistence of highly endemic parasitic, bacterial and viral diseases makes individuals and populations vulnerable to emerging and re-emerging diseases. Evaluating the role of multiple component, often interacting, causes of disease may be impossible with research tools designed to isolate single causes. Similarly, it may not be possible to identify statistically significant treatment effects, even for interventions known to be effective, when multiple morbidities are present. Evidence continues to accumulate that nutritional deficiencies, bacterial, viral and parasitic coinfections accelerate HIV transmission. Inclusion of antiparasitics and other beneficial interventions in HIV-prevention protocols is impeded by reliance on inappropriate methodologies. Lack of full scientific certainty is not a reason for postponing safe, cost-effective measures to prevent irreversible damage.

Combination antiretroviral therapy and chronic HIV infection affect serum retinoid concentrations: longitudinal and cross-sectional assessments

Background

Several lines of evidence suggest that retinoids (retinol-ROL or vitamin A, and its active metabolites, retinoic acids-RAs) play important pathogenic roles in HIV infection and combination antiretroviral therapy (cART)-related events. We previously reported that antiretrovirals alter RAs synthesis in vitro. We hypothesised that in vivo serum retinoid concentrations are affected by both cART and HIV infection. This might explain several clinical and laboratory abnormalities reported in HIV-infected patients receiving cART.

Methods

The effects of optimal cART and chronic HIV on serum retinoids were firstly assessed longitudinally in 10 HIV-infected adults (group1 = G1): twice while on optimal cART (first, during long-term and second, during short term cART) and twice during 2 cART interruptions when HIV viral load (VL) was detectable. Retinoid concentrations during optimal long term cART in G1 were compared with cross-sectional results from 12 patients (G2) with suboptimal cART (detectable VL) and from 28 healthy adults (G3). Serum retinoids were measured by HPLC with ultraviolet detection. Retinoid concentrations were correlated with VL, CD4⁺ T- cell count and percentages, CD8⁺38⁺ fluorescence, triglycerides, cholesterol and C-peptide serum levels.

Results

During optimal cART, G1 participants had drastically reduced RAs (0.5 ± 0.3 μg/dL; P < 0.01) but the highest ROL (82 ± 3.0 μg/dL) concentrations. During cART interruptions in these patients, RAs slightly increased whereas ROL levels diminished significantly (P < 0.05). G3 had the highest RAs levels (7.2 ± 1.1 μg/dL) and serum ROL comparable to values in North Americans. Serum ROL was decreased in G2 (37.7 ± 3.2 μg/dL; P < 0.01). No correlations were noted between RA and ROL levels or between retinoid concentrations and CD4⁺ T- cell count, CD8⁺38⁺ fluorescence, VL. ROL correlated with triglycerides and cholesterol in G1 (r_s = 0.8; P = 0.01).

Conclusions

Serum RAs levels are significantly diminished by cART, whereas ROL concentrations significantly decreased during uncontrolled HIV infection but augmented with optimal cART. These alterations in retinoid concentrations may affect the expression of retinoid-responsive genes involved in metabolic, hormonal and immune processes and be responsible for some adverse events observed in HIV-infected persons treated with antiretrovirals. Further studies should assess concomitant serum and intracellular retinoid levels in different clinical situations in larger, homogenous populations.

Vitamin A supplementation for the prevention of morbidity and mortality in infants six months of age or less

BACKGROUND

Vitamin A deficiency is a significant public health problem in low and middle income countries. Vitamin A supplementation (VAS) provided to lactating postpartum mothers or to infants less than six months of age are two possible strategies to improve the nutrition of infants at high risk of vitamin A deficiency and thus potentially reduce their mortality and morbidity.

OBJECTIVES

To evaluate the effect of:1. VAS in postpartum breast feeding mothers in low and middle income countries, irrespective of antenatal VAS status, on mortality, morbidity and adverse effects in their infants up until the age of one year.2. VAS initiated in the first half of infancy (< 6 months of age) in low and middle income countries, irrespective of maternal antenatal or postnatal VAS status, on mortality, morbidity and adverse effects up until the age of one year.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), EMBASE, MEDLINE, clinical trials websites, conference proceedings, donor agencies, 'experts' and researchers (up to October 15, 2010).

SELECTION CRITERIA

Randomized or quasi-randomised, individually or cluster randomised, placebo controlled trials involving synthetic VAS provided to the postpartum mothers or their infants up to the age of six months were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the studies for their risk of bias and collected data on outcomes.

MAIN RESULTS

Of the 18 included studies, eight provided information on maternal VAS and 15 on infant VAS.For maternal VAS, there was no evidence of a reduced risk of mortality of their babies during infancy (96,203 participants, seven studies, high quality evidence; random-effects model RR 1.00, 95% CI 0.94 to 1.06, P = 0.9; test of heterogeneity I(2) = 0%, P = 0.9) or in the neonatal period (moderate quality evidence); nor of morbidities (very low quality evidence).  For infant VAS, there was no evidence of a reduced risk of mortality during infancy (59,402 participants, nine studies, moderate quality evidence; random-effects model RR 0.97, 0.83 to 1.12, P = 0.65; test of heterogeneity I(2) = 49%, P = 0.05) or in the neonatal period, nor morbidities (low quality evidence), but an increased risk of bulging fontanelle (32,978 participants, 10 studies, low quality evidence; random-effects model RR 1.55, 1.05 to 2.28, P = 0.03; test of heterogeneity I(2) = 68%, P = 0.0009).

AUTHORS' CONCLUSIONS

There is no convincing evidence that either maternal postpartum or infant vitamin A supplementation results in a reduction in infant mortality or morbidity in low and middle income countries.

Impact of vitamin A supplementation on infant and childhood mortality

Introduction

Vitamin A is important for the integrity and regeneration of respiratory and gastrointestinal epithelia and is involved in regulating human immune function. It has been shown previously that vitamin A has a preventive effect on all-cause and disease specific mortality in children under five. The purpose of this paper was to get a point estimate of efficacy of vitamin A supplementation in reducing cause specific mortality by using Child Health Epidemiology Reference Group (CHERG) guidelines.

Methods

A literature search was done on PubMed, Cochrane Library and WHO regional data bases using various free and Mesh terms for vitamin A and mortality. Data were abstracted into standardized forms and quality of studies was assessed according to standardized guidelines. Pooled estimates were generated for preventive effect of vitamin A supplementation on all-cause and disease specific mortality of diarrhea, measles, pneumonia, meningitis and sepsis. We did a subgroup analysis for vitamin A supplementation in neonates, infants 1-6 months and children aged 6-59 months. In this paper we have focused on estimation of efficacy of vitamin A supplementation in children 6-59 months of age. Results for neonatal vitamin A supplementation have been presented, however no recommendations are made as more evidence on it would be available soon.

Results

There were 21 studies evaluating preventive effect of vitamin A supplementation in community settings which reported all-cause mortality. Twelve of these also reported cause specific mortality for diarrhea and pneumonia and six reported measles specific mortality. Combined results from six studies showed that neonatal vitamin A supplementation reduced all-cause mortality by 12 % [Relative risk (RR) 0.88; 95 % confidence interval (CI) 0.79-0.98]. There was no effect of vitamin A supplementation in reducing all-cause mortality in infants 1-6 months of age [RR 1.05; 95 % CI 0.88-1.26]. Pooled results for preventive vitamin A supplementation showed that it reduced all-cause mortality by 25% [RR 0.75; 95 % CI 0.64-0.88] in children 6-59 months of age. Vitamin A supplementation also reduced diarrhea specific mortality by 30% [RR 0.70; 95 % CI 0.58-0.86] in children 6-59 months. This effect has been recommended for inclusion in the Lives Saved Tool. Vitamin A supplementation had no effect on measles [RR 0.71, 95% CI: 0.43-1.16], meningitis [RR 0.73, 95% CI: 0.22-2.48] and pneumonia [RR 0.94, 95% CI: 0.67-1.30] specific mortality.

Conclusion

Preventive vitamin A supplementation reduces all-cause and diarrhea specific mortality in children 6-59 months of age in community settings in developing countries.

Dealing with substantial heterogeneity in Cochrane reviews. Cross-sectional study

BACKGROUND

Dealing with heterogeneity in meta-analyses is often tricky, and there is only limited advice for authors on what to do. We investigated how authors addressed different degrees of heterogeneity, in particular whether they used a fixed effect model, which assumes that all the included studies are estimating the same true effect, or a random effects model where this is not assumed.

METHODS

We sampled randomly 60 Cochrane reviews from 2008, which presented a result in its first meta-analysis with substantial heterogeneity (I2 greater than 50%, i.e. more than 50% of the variation is due to heterogeneity rather than chance). We extracted information on choice of statistical model, how the authors had handled the heterogeneity, and assessed the methodological quality of the reviews in relation to this.

RESULTS

The distribution of heterogeneity was rather uniform in the whole I2 interval, 50-100%. A fixed effect model was used in 33 reviews (55%), but there was no correlation between I2 and choice of model (P = 0.79). We considered that 20 reviews (33%), 16 of which had used a fixed effect model, had major problems. The most common problems were: use of a fixed effect model and lack of rationale for choice of that model, lack of comment on even severe heterogeneity and of reservations and explanations of its likely causes. The problematic reviews had significantly fewer included trials than other reviews (4.3 vs. 8.0, P = 0.024). The problems became less pronounced with time, as those reviews that were most recently updated more often used a random effects model.

CONCLUSION

One-third of Cochrane reviews with substantial heterogeneity had major problems in relation to their handling of heterogeneity. More attention is needed to this issue, as the problems we identified can be essential for the conclusions of the reviews.

The cost-effectiveness of preventing mother-to-child transmission of HIV in low- and middle-income countries: systematic review

BACKGROUND

Although highly effective prevention interventions exist, the epidemic of paediatric HIV continues to challenge control efforts in resource-limited settings. We reviewed the cost-effectiveness of interventions to prevent mother-to-child transmission (MTCT) of HIV in low- and middle-income countries (LMICs). This article presents syntheses of evidence on the costs, effects and cost-effectiveness of HIV MTCT strategies for LMICs from the published literature and evaluates their implications for policy and future research.

METHODS

Candidate studies were identified through a comprehensive database search including PubMed, Embase, Cochrane Library, and EconLit restricted by language (English or French), date (January 1st, 1994 to January 17th, 2011) and article type (original research). Articles reporting full economic evaluations of interventions to prevent or reduce HIV MTCT were eligible for inclusion. We searched article bibliographies to identify additional studies. Two authors independently assessed eligibility and extracted data from studies retained for review. Study quality was appraised using a modified BMJ checklist for economic evaluations. Data were synthesised in narrative form.

RESULTS

We identified 19 articles published in 9 journals from 1996 to 2010, 16 concerning sub-Saharan Africa. Collectively, the articles suggest that interventions to prevent paediatric infections are cost-effective in a variety of LMIC settings as measured against accepted international benchmarks. In concentrated epidemics where HIV prevalence in the general population is very low, MTCT strategies based on universal testing of pregnant women may not compare well against cost-effectiveness benchmarks, or may satisfy formal criteria for cost-effectiveness but offer a low relative value as compared to competing interventions to improve population health.

CONCLUSIONS AND RECOMMENDATIONS

Interventions to prevent HIV MTCT are compelling on economic grounds in many resource-limited settings and should remain at the forefront of global HIV prevention efforts. Future cost-effectiveness analyses can help to ensure that pMTCT interventions for LMICs reach their full potential by focussing on unanswered questions in four areas: local assessment of rapidly evolving HIV MTCT options; strategies to improve coverage and reach underserved populations; evaluation of a more comprehensive set of MTCT approaches including primary HIV prevention and reproductive counselling; integration of HIV MTCT and other sexual and reproductive health services.

Vitamin A supplementation for reducing the risk of mother-to-child transmission of HIV infection

BACKGROUND

Observational studies of pregnant women in sub-Saharan Africa have shown that low serum vitamin A levels are associated with an increased risk of mother-to-child transmission (MTCT) of HIV. Vitamin A is cheap and easily provided through existing health services in low-income settings. It is thus important to determine the effect of routine supplementation of HIV positive pregnant or breastfeeding women with this vitamin on the risk of MTCT of HIV, which currently results in more than 1000 new HIV infections each day world-wide.

OBJECTIVES

We aimed to assess the effect of antenatal and or postpartum vitamin A supplementation on the risk of MTCT of HIV as well as infant and maternal mortality and morbidity.

SEARCH STRATEGY

In June 2010 we searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, AIDS Education Global Information System, and WHO International Clinical Trials Registry Platform; and checked reference lists of identified articles for any studies published after the earlier version of this review was updated in 2008.

SELECTION CRITERIA

We selected randomised controlled trials conducted in any setting that compared vitamin A supplementation with placebo in known HIV-infected pregnant or breastfeeding women.

DATA COLLECTION AND ANALYSIS

At least two authors independently assessed trial eligibility and quality and extracted data. We calculated relative risks (RR) or mean differences (MD), with their 95% confidence intervals (CI) for each study. We conducted meta-analysis using a fixed-effects method (when there was no significant heterogeneity between study results, i.e. P>0.1) or the random-effects method (when there was significant heterogeneity), and report the Higgins' statistic for all pooled effect measures.

MAIN RESULTS

Five randomised controlled trials which enrolled 7,528 HIV-infected women (either during pregnancy or the immediate postpartum period) met our inclusion criteria. These trials were conducted in Malawi, South Africa, Tanzania, and Zimbabwe between 1995 and 2005. We combined the results of these trials and found no evidence that vitamin A supplementation has an effect on the risk of MTCT of HIV (4 trials, 6517 women: RR 1.04, 95% CI 0.87 to 1.24; I(2)=68%). However, antenatal vitamin A supplementation significantly improved birth weight (3 trials, 1809 women: MD 89.78, 95%CI 84.73 to 94.83; I(2)=33.0%), but there was no evidence of an effect on preterm births (3 trials, 2110 women: RR 0.88, 95%CI 0.65 to 1.19; I(2)=58.1%), stillbirths (4 trials, 2855 women: RR 0.99, 95%CI 0.68 to 1.43; I(2)=0%), deaths by 24 months (2 trials, 1635 women: RR 1.03, 95%CI 0.88 to 1.20; I(2)=0%), postpartum CD4 levels (1 trial, 727 women: MD -4.00, 95% CI -51.06 to 43.06), and maternal death ( 1 trial, 728 women: RR 0.49, 95%CI 0.04 to 5.37).

AUTHORS' CONCLUSIONS

Current best evidence shows that antenatal or postpartum vitamin A supplementation probably has little or no effect on mother-to-child transmission of HIV. According to the GRADE classification, the quality of this evidence is moderate; implying that the true effect of vitamin A supplementation on the risk of mother-to-child transmission of HIV is likely to be close to the findings of this review, but that there is also a possibility that it is substantially different.

Micronutrient supplementation in children and adults with HIV infection

BACKGROUND

Micronutrient deficiencies are widespread and compound the effects of HIV disease; micronutrient supplements may be effective and safe in reducing this burden.

OBJECTIVES

To assess whether micronutrient supplements are effective and safe in reducing mortality and morbidity in adults and children with HIV infection.

SEARCH STRATEGY

The CENTRAL, EMBASE, PubMed, and GATEWAY databases were searched for randomised controlled trials of micronutrient supplements using the search methods of the Cochrane HIV/AIDS Group.

SELECTION CRITERIA

Randomised controlled trials were selected that compared the effects of micronutrient supplements (vitamins, trace elements, and combinations of these) with other supplements, placebo or no treatment on mortality, morbidity, pregnancy outcomes, immunologic indicators, and anthropometric measures in HIV-infected adults and children. Any adverse effects of supplementation were recorded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials, appraised trial quality for risk of bias using standardised criteria, and extracted data using standardised forms.

MAIN RESULTS

Sixteen additional trials are included in this update to the original Cochrane review (Irlam 2005). Overall, 30 trials involving 22 120 participants are reviewed: 20 trials of single supplements (vitamin A, vitamin D, zinc, selenium) and 10 of multiple micronutrients. Eight trials were undertaken in child populations.None of the six trials of vitamin A or beta-carotene supplementation in adults demonstrated any significant reduction in HIV disease progression. Vitamin A halved all-cause mortality in a meta-analysis of three trials in African children, had inconsistent impacts on diarrhoeal and respiratory morbidity, and improved short-term growth in one trial. No significant adverse effects of vitamin A in adults or children have been reported.Zinc supplements reduced diarrhoeal morbidity and had no adverse effects on disease progression in a single safety trial in South African children. No significant clinical benefits were found from zinc supplementation of pregnant Tanzanian women or Peruvian adults with persistent diarrhoea.Selenium reduced diarrhoeal morbidity in pregnant women in Tanzania, and reduced viral load in two separate small trials in American adults.Single trials of vitamin D supplements in adults, and in adolescents and children, demonstrated safety but no clinical benefits.Multiple micronutrient supplements conferred multiple clinical benefits to pregnant women and their offspring in a large Tanzanian trial. Supplementation in another Tanzanian trial reduced the recurrence of pulmonary TB and increased weight gain in co-infected patients. No significant adverse effects were reported.

AUTHORS' CONCLUSIONS

Multiple micronutrient supplements reduced morbidity and mortality in HIV-infected pregnant women and their offspring and also improved early child growth in one large randomised controlled trial in Africa. Additional research is needed to determine if these are generalisable findings. Vitamin A supplementation is beneficial and safe in HIV-infected children, but further evidence is needed to establish if supplementation confers similar benefits in HIV-infected adults. Zinc is safe in HIV-infected adults and children. It may have similar benefits in HIV-infected children and adults, and uninfected children with diarrhoea, as it does in HIV-uninfected children.Further trials of single supplements (vitamin D, zinc, and selenium) are required to build the evidence base. The long-term clinical benefits, adverse effects, and optimal formulation of multiple micronutrient supplements require further investigation in individuals with diverse disease status. 

Vitamin A supplementation for preventing morbidity and mortality in children from 6 months to 5 years of age

BACKGROUND

Vitamin A deficiency (VAD) is a major public health problem in low and middle income countries affecting 190 million children under 5. VAD can lead to many adverse health consequences, including death.

OBJECTIVES

To evaluate the effect of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged 6 months to 5 years.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2010 Issue 2),  MEDLINE (1950 to April Week 2 2010), EMBASE (1980 to 2010 Week 16), Global Health (1973 to March 2010), Latin American and Caribbean Health Sciences (LILACS), metaRegister of Controlled Trials and African Index Medicus (27 April 2010).

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster RCTs evaluating the effect of synthetic VAS in children aged 6 months to 5 years living in the community. We excluded studies concerned with children in hospital and children with disease or infection. We excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods or beta-carotene supplementation.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. Data were double abstracted and discrepancies were resolved by discussion. Meta-analyses were performed for outcomes including all-cause and cause-specific mortality, disease, vision, and side-effects.

MAIN RESULTS

43 trials involving 215,633 children were included. A meta-analysis for all-cause mortality included 17 trials comprising 194,795 children with 3536 deaths in both groups. At follow-up, there was a 24% observed reduction in the risk of all-cause mortality for Vitamin A compared with Control (Relative risk (RR) = 0.76 [95% confidence interval (CI) 0.69, 0.83]). Seven trials reported diarrhoea mortality and a 28% overall reduction for VAS (RR = 0.72 [0.57, 0.91]). There was no significant effect of VAS on cause specific mortality of measles, respiratory disease and meningitis. VAS reduced incidence of diarrhoea (RR = 0.85 [0.82, 0.87]) and measles morbidity (RR = 0.50 [0.37, 0.67]); 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 = 2.75 [1.81, 4.19]).

AUTHORS' CONCLUSIONS

VAS is effective in reducing all-cause mortality by about 24% compared to no treatment. In our opinion, given the evidence that VAS causes considerable reduction in child mortality, further placebo-controlled trials of VAS in children between 6 months and 5 years of age are not required. There is a need for further studies comparing different doses and delivery mechanisms (for example, fortification).

Evidence for perinatal and child health care guidelines in crisis settings: can Cochrane help?

BACKGROUND

It is important that healthcare provided in crisis settings is based on the best available research evidence. We reviewed guidelines for child and perinatal health care in crisis situations to determine whether they were based on research evidence, whether Cochrane systematic reviews were available in the clinical areas addressed by these guidelines and whether summaries of these reviews were provided in Evidence Aid.

METHODS

Broad internet searches were undertaken to identify relevant guidelines. Guidelines were appraised using AGREE and the clinical areas that were relevant to perinatal or child health were extracted. We searched The Cochrane Database of Systematic Reviews to identify potentially relevant reviews. For each review we determined how many trials were included, and how many were conducted in resource-limited settings.

RESULTS

Six guidelines met selection criteria. None of the included guidelines were clearly based on research evidence. 198 Cochrane reviews were potentially relevant to the guidelines. These reviews predominantly addressed nutrient supplementation, breastfeeding, malaria, maternal hypertension, premature labour and prevention of HIV transmission. Most reviews included studies from developing settings. However for large portions of the guidelines, particularly health services delivery, there were no relevant reviews. Only 18 (9.1%) reviews have summaries in Evidence Aid.

CONCLUSIONS

We did not identify any evidence-based guidelines for perinatal and child health care in disaster settings. We found many Cochrane reviews that could contribute to the evidence-base supporting future guidelines. However there are important issues to be addressed in terms of the relevance of the available reviews and increasing the number of reviews addressing health care delivery.

Reducing stillbirths: behavioural and nutritional interventions before and during pregnancy

BACKGROUND

The vast majority of global stillbirths occur in low- and middle-income countries, and in many settings, the majority of stillbirths occur antenatally, prior to the onset of labour. Poor nutritional status, lack of antenatal care and a number of behaviours increase women's risk of stillbirth in many resource-poor settings. Interventions to reduce these risks could reduce the resulting burden of stillbirths, but the evidence for the impact of such interventions has not yet been comprehensively evaluated.

METHODS

This second paper of a systematic review of interventions that could plausibly impact stillbirth rates covers 12 different interventions relating to behavioural and socially mediated risk factors, including exposures to harmful practices and substances, antenatal care utilisation and quality, and maternal nutrition before and during pregnancy. The search strategy reviewed indexed medical journals on PubMed and the Cochrane Library. If any eligible randomised controlled trials were identified that were published after the most recent Cochrane review, they were added to generate new meta-analyses. Interventions covered in this paper have a focus on low- and middle-income countries, both because of the large burden of stillbirths and because of the high prevalence of risk factors including maternal malnutrition and harmful environmental exposures. The reviews and studies belonging to these interventions were graded and conclusions derived about the evidence of benefit of these interventions.

RESULTS

From a programmatic perspective, none of the interventions achieved clear evidence of benefit. Evidence for some socially mediated risk factors were identified, such as exposure to indoor air pollution and birth spacing, but still require the development of appropriate interventions. There is a need for additional studies on culturally appropriate behavioural interventions and clinical trials to increase smoking cessation and reduce exposure to smokeless tobacco. Balanced protein-energy supplementation was associated with reduced stillbirth rates, but larger well-designed trials are required to confirm findings. Peri-conceptional folic acid supplementation significantly reduces neural tube defects, yet no significant associated reductions in stillbirth rates have been documented. Evidence for other nutritional interventions including multiple micronutrient and Vitamin A supplementation is weak, suggesting the need for further research to assess potential of nutritional interventions to reduce stillbirths.

CONCLUSION

Antenatal care is widely used in low- and middle-income countries, and provides a natural facility-based contact through which to provide or educate about many of the interventions we reviewed. The impact of broader socially mediated behaviors, such as fertility decision-making, access to antenatal care, and maternal diet and exposures like tobacco and indoor air pollution during pregnancy, are poorly understood, and further research and appropriate interventions are needed to test the association of these behaviours with stillbirth outcomes. For most nutritional interventions, larger randomised controlled trials are needed which report stillbirths disaggregated from composite perinatal mortality. Many antepartum stillbirths are potentially preventable in low- and middle-income countries, particularly through dietary and environmental improvement, and through improving the quality of antenatal care - particularly including diagnosis and management of high-risk pregnancies - that pregnant women receive.

Reducing stillbirths: prevention and management of medical disorders and infections during pregnancy

BACKGROUND

An estimated two-thirds of the world's 3.2 million stillbirths occur antenatally, prior to labour, and are often overlooked in policy and programs. Poorly recognised, untreated or inadequately treated maternal infections such as syphilis and malaria, and maternal conditions including hypertensive disorders, are known risk factors for stillbirth.

METHODS

We undertook a systematic review of the evidence for 16 antenatal interventions with the potential to prevent stillbirths. We searched a range of sources including PubMed and the Cochrane Library. For interventions with prior Cochrane reviews, we conducted additional meta-analyses including eligible newer randomised controlled trials following the Cochrane protocol. We focused on interventions deliverable at the community level in low-/middle-income countries, where the burden of stillbirths is greatest.

RESULTS

Few of the studies we included reported stillbirth as an outcome; most that did were underpowered to assess this outcome. While Cochrane reviews or meta-analyses were available for many interventions, few focused on stillbirth or perinatal mortality as outcomes, and evidence was frequently conflicting. Several interventions showed clear evidence of impact on stillbirths, including heparin therapy for certain maternal indications; syphilis screening and treatment; and insecticide-treated bed nets for prevention of malaria. Other interventions, such as management of obstetric intrahepatic cholestasis, maternal anti-helminthic treatment, and intermittent preventive treatment of malaria, showed promising impact on stillbirth rates but require confirmatory studies. Several interventions reduced known risk factors for stillbirth (e.g., anti-hypertensive drugs for chronic hypertension), yet failed to show statistically significant impact on stillbirth or perinatal mortality rates. Periodontal disease emerged as a clear risk factor for stillbirth but no interventions have reduced stillbirth rates.

CONCLUSION

Evidence for some newly recognised risk factors for stillbirth, including periodontal disease, suggests the need for large, appropriately designed randomised trials to test whether intervention can minimise these risks and prevent stillbirths. Existing evidence strongly supports infection control measures, including syphilis screening and treatment and malaria prophylaxis in endemic areas, for preventing antepartum stillbirths. These interventions should be incorporated into antenatal care programs based on attributable risks and burden of disease.

Neonatal vitamin A supplementation for prevention of mortality and morbidity in infancy: systematic review of randomised controlled trials

OBJECTIVE

To evaluate the effect of neonatal vitamin A supplementation on infant mortality, morbidity and early adverse effects.

DESIGN

Systematic review, meta-analysis, and meta-regression of randomised controlled trials.

DATA SOURCES

Electronic databases and hand search of reviews; abstracts and proceedings of conferences. Review methods Randomised or quasi-randomised or cluster randomised, placebo controlled trials evaluating the effect of prophylactic, neonatal (<1 month) supplementation with synthetic vitamin A on mortality or morbidity within infancy (<1 year), and early adverse effects (

RESULTS

The six included trials were from developing countries. There was no convincing evidence of a reduced risk of mortality during infancy (relative risk 0.92, 95% confidence interval 0.75 to 1.12, P=0.393 random effect; I(2)=54.1%) or of an increase in early adverse effects including bulging fontanelle (1.16, 0.81 to 1.65, P=0.418; I(2)=65.3%). No variable emerged as a significant predictor of mortality, but data for important risk groups (high maternal night blindness prevalence and low birth weights) were restricted. Limited data (from one to four trials) did not indicate a reduced risk of mortality during the neonatal period (0.90, 0.75 to 1.08, P=0.270; I(2)=0%), cause specific mortality, common morbidities (diarrhoea and others), and admission to hospital. There was, however, evidence of an increased risk of acute respiratory infection and a reduced risk of clinic visits.

CONCLUSIONS

There is no convincing evidence of a reduced risk of mortality and possibly morbidity or of increased early adverse effects after neonatal supplementation with vitamin A. There is thus no justification for initiating such supplementation as a public health intervention in developing countries for reducing infant mortality and morbidity.

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MESH Headings

• Child, Preschool
• Dietary Supplements
• Humans
• Infant
• Infant Mortality
• Perinatal Care
• Randomized Controlled Trials as Topic
• Regression Analysis
• Risk Factors
• Treatment Outcome
• Vitamin A/administration & dosage
• Vitamins/administration & dosage

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Affiliation(s)

Siddhartha Gogia Department of Paediatrics and Clinical Epidemiology, Sitaram Bhartia Institute of Science and Research, B-16 Qutab Institutional Area, New Delhi 110016, India
Harshpal Singh Sachdev

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Markers of innate immune function are associated with vitamin a stores in men

Recommendations for vitamin A intake and liver stores are based on maintaining normal vision. We propose that higher levels may be required to maintain normal innate immune function. To test this hypothesis, we conducted an 8-wk residential study among 36 healthy Bangladeshi men with low vitamin A stores. Subjects were randomized to receive vitamin A (240 mg in 4 doses) or placebo during study wk 2 and 3. They received 2 vaccines during wk 5 and vitamin A stores were estimated by isotopic dilution at wk 8. The serum concentration of the chemokine interferon-gamma-induced protein 10, a component of T-helper 1 (Th1) response, increased significantly after supplementation and was positively and significantly associated with vitamin A stores. Blood concentrations of natural killer (NK) and NK T-cells, which have anticancer and antiviral activity, were positively associated with stores (P < 0.05), as was monocyte oxidative burst (P < 0.05), a marker of bacterial killing ability. However, serum interleukin (IL)-6 and IL-17, cytokines that regulate the antibacterial Th17 response, were significantly and negatively associated with stores, as was production of the regulatory cytokine IL-10 by whole-blood cultures stimulated with bacterial lipopolysaccharide. In summary, vitamin A stores were positively associated with several measures of innate immune activity across a broad range of stores, suggesting that vitamin A enhances protection against diverse pathogens even at concentrations above those needed to maintain normal vision. The negative association of stores with serum IL-6 and IL-17 suggests that not all protective responses are similarly enhanced by vitamin A.

Disruption of Rxra gene in thymocytes and T lymphocytes modestly alters lymphocyte frequencies, proliferation, survival and T helper type 1/type 2 balance

Retinoid X receptor (RXR) agonists, including the vitamin A metabolite 9-cis retinoic acid, decrease T-lymphocyte apoptosis and promote T helper type 2 (Th2) development ex vivo. To examine the in vivo role of RXR-alpha in T-lymphocyte development and function, we disrupted the Rxra gene in thymocytes and T lymphocytes using cyclization recombinase (Cre)-loxP-mediated excision of Rxra exon 4. Expression of Cre was targeted to these cells using the Lck promoter. Successful disruption of exon 4 was seen in thymus and T lymphocytes. Mice were healthy and the thymus, spleen and lymph nodes appeared normal. However, knockout mice had a lower percentage of double-positive (CD4(+) CD8(+)) and a higher percentage of double-negative thymocytes than wild-type mice. The percentage of splenic B lymphocytes was lower in unimmunized and ovalbumin-immunized knockout mice and the percentage of T lymphocytes was lower in immunized knockout mice. Ex vivo proliferation was decreased and apoptosis was increased in T lymphocytes from knockout mice. Memory CD4(+) T lymphocytes from knockout mice produced more interferon-gamma and interleukin-2 (IL-2) and less IL-5 and IL-10 than memory cells from wild-type mice, indicating a Th1 bias in vivo. However, Rxra disruption did not similarly bias ex vivo differentiation of naive CD4(+) T lymphocytes, nor did Rxra disruption alter the serum immunoglobulin G1/immunoglobulin G2a response to immunization. In summary, disruption of Rxra altered the percentages of T and B lymphocytes, produced a Th1 bias in vivo, and altered T-lymphocyte proliferation and apoptosis ex vivo. These differences were modest in magnitude and their impact on disease resistance is yet to be examined.

Vitamin A supplementation for reducing the risk of mother-to-child transmission of HIV infection

BACKGROUND

Mother-to-child transmission (MTCT) of HIV is the dominant mode of acquisition of HIV infection for children, currently resulting in more than 2000 new paediatric HIV infections each day worldwide.

OBJECTIVES

To assess the effects of antenatal and intrapartum vitamin A supplementation on the risk of MTCT of HIV infection and infant and maternal mortality and morbidity, and the tolerability of vitamin A supplementation.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, AIDSLINE, LILACS, AIDSTRIALS, and AIDSDRUGS, using standardised methodological filters for identifying trials. We also searched reference lists of identified articles, relevant editorials, expert opinions and letters to journal editors, and abstracts or proceedings of relevant conferences; and contacted subject experts, agencies, organisations, academic centres, and pharmaceutical companies. There were no language restrictions.

SELECTION CRITERIA

Randomised trials comparing vitamin A supplementation with no vitamin A supplementation in known HIV infected pregnant women. Trials had to include an estimate of the effect of vitamin A supplementation on MTCT of HIV and or any other adverse pregnancy outcome to be included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and quality and extracted data. Effect measures (odds ratio [OR] for binary variables and weighted mean difference [WMD] for continuous variables) with their 95% confidence intervals (CI) were estimated for each study and combined using the fixed effect (Mantel-Haenszel) method, by intention to treat. Heterogeneity between studies was examined by graphical inspection of results followed by a chi-square test of homogeneity.

MAIN RESULTS

Four trials, which enrolled 3,033 HIV-infected pregnant women, are included in this review. There was no evidence of an effect of vitamin A supplementation on MTCT of HIV infection (OR 1.14, 95% CI 0.93 to 1.38). There was evidence of heterogeneity between the three trials with information on MTCT of HIV (I(2) =75.7%, P=0.02). While the trials conducted in South Africa (OR 0.98, 95% CI 0.67 to 1.42 at three months) and Malawi (OR 0.78, 95% CI 0.53 to 1.15 at 24 months) did not find evidence that the effect of Vitamin A supplementation was different from that of placebo, the trial in Tanzania did find evidence that vitamin A supplementation increased the risk of MTCT of HIV (OR 1.53, 95% CI 1.15 to 2.04 at 24 months). Vitamin A supplementation significantly improved birth weight (WMD 89.78, 95% CI 84.73 to 94.83), but there was no evidence of an effect of vitamin A supplementation on stillbirths (OR 0.99, 95% CI 0.67 to 1.46), preterm births (OR 0.89, 95% CI 0.71 to 1.11), death by 24 months among live births (OR 1.11, 95% CI 0.88 to 1.40), postpartum CD4 levels (WMD -4.00, 95% CI -51.06 to 43.06), and maternal death (OR 0.49, 95%CI 0.04 to 5.40).

IMPLICATIONS FOR PRACTICE

Currently available evidence do not support the use of vitamin A supplementation of HIV-infected pregnant women to reduce MTCT of HIV, though there is an indication that vitamin A supplementation improves birth weight.

IMPLICATIONS FOR RESEARCH

The awaited publication of data from a large trial involving 4,495 HIV infected pregnant women in Harare (Zimbabwe Vitamin A for Mothers and Babies Project), will further clarify the effect of vitamin A supplementation on MTCT of HIV. The current review will be updated as soon as the trial is published.

Vaginal chlorhexidine during labour for preventing maternal and neonatal infections (excluding Group B Streptococcal and HIV)

BACKGROUND

The incidence of chlorioamnionitis occurs in between 8 to 12 women for every 1000 live births and 96% of the cases of chlorioamnionitis are due to ascending infection. Following spontaneous vaginal delivery, 1% to 4% of women develop postpartum endometritis. The incidence of neonatal sepsis is 0.5% to 1% of all infants born. Maternal vaginal bacteria are the main agents for these infections. It is reasonable to speculate that prevention of maternal and neonatal infections might be possible by washing the vagina and cervix with an antibacterial agent for all women during labour. Chlorhexidine belongs to the class of compounds known as the bis-biguanides. Chlorhexidine has antibacterial action against a wide range of aerobic and anaerobic bacteria, including those implicated in peripartal infections.

OBJECTIVES

To evaluate the effectiveness and side-effects of chlorhexidine vaginal douching during labour in reducing maternal and neonatal infections (excluding Group B Streptococcal and HIV).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (July 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 4, 2002), MEDLINE (from 1966 to 2002), EMBASE (from 1980 to 2002), CINAHL (from 1982 to 2002) and LILACS (from 1982 to 2002).

SELECTION CRITERIA

Randomized or quasi-randomized trials comparing chlorhexidine vaginal douching during labour with placebo or other vaginal disinfectant to prevent (reduce) maternal and neonatal infections (excluding Group B Streptococcal and HIV).

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial eligibility and quality, extracted and entered the data into the RevMan software and interpreted the data. A third reviewer analysed and interpreted the data. The fourth reviewer also interpreted the data.

MAIN RESULTS

Three studies (3012 participants) were included. There was no evidence of an effect of vaginal chlorhexidine during labour in preventing maternal and neonatal infections. Although the data suggest a trend in reducing postpartum endometritis, the difference was not statistically significant (relative risk 0.83; 95% confidence interval 0.61 to 1.13).

REVIEWERS' CONCLUSIONS

There is no evidence to support the use of vaginal chlorhexidine during labour in preventing maternal and neonatal infections. There is a need for a well-designed randomized controlled trial using appropriate concentration and volume of vaginal chlorhexidine irrigation solution and with adequate sample size.