United Nations - Administrative Committee on Coordination - Subcommittee on Nutrition (ACC/SCN)

Foreword

Acknowledgements

Signators of the Report

Abstract

Summary

1. Introduction, Statement of Purpose and Organization of the Report

2. Epidemiology of Vitamin A Deficiency

Historical Background
Epidemiology: Localization of Deficiency and Identification of Groups at Risk

Age and Sex as Predictors of Risk of Xerophthalmia

Strategies of Intervention

Hypervitaminosis A

Summary: Points Arising from the Epidemiology of Vitamin A

3. Vitamin A and Biological Functions: Consideration of Possible Biological Bases of Morbidity and Mortality Effects

Introduction
Retinol Accumulation and Transport
Signs and Symptoms of Vitamin A Deficiency
Changes in Epithelial Cells and Tissues
Decreased Resistance to Infection
Immune Responses

Lymphoid Cells and Organs
Cell-mediated Immunity
Antibody Responses

Influence of Vitamin A Administration on Immune Responses
Summary and Hypotheses

4. Controlled Trials of Vitamin and Morbidity in Young Children

Introduction
Objective and Approach of Present Review
Morbidity: Terminology and Methodologic Considerations
Controlled Trials of Vitamin A Supplementation and Morbidity
Review of Field Trials (Table 4.1)

Studies Reporting Null Results with Respect to Incidence, Duration or Prevalence
Studies Reporting Reductions in Incidence, Duration or Prevalence
Studies Showing an Adverse Effect of Vitamin A on Incidence, Duration or Prevalence

Vitamin A Supplementation in Children with Measles and Diarrhoea (Table 4.2)
Vitamin A Supplementation in Children at Risk of Respiratory Infection (Table 4.3)
Discussion

What are the Effects on Incidence and Duration of Diarrhoea and Respiratory Infections?
Does Vitamin A Supplementation Increase the Risk of Respiratory Infections?
Does Vitamin A Supplementation Reduce the Severity of Infections?

Major Conclusions
Research Recommendations

5. Vitamin A and Young Child Mortality

Introduction: Studies Included
Analytical Objectives
Treatment of Data: Preparation for Analysis
Analytical Methods
“Does Vitamin A Supplementation Affect Mortality?”
Impact of Age and Gender
Cause-specific Mortality
When and Where is Vitamin A Likely to be More Effective?

Demographic Profile
Mortality Profile
Baseline Anthropometry
Prevalence of Xerophthalmia
Periodicity and Magnitude of Dosing

Prediction of Effectiveness in a New Situation
Relative and Absolute Effects: Implications of the Difference
Comparison of Present Results with Other Meta-Analyses
Discussion and Conclusions: Mortality Effects
Research Recommendations
Sources of Study Data

6. Discussion and Conclusions

References Cited

Review Annex: Assessments Offered by Invited Reviewers

Technical Annex

Theoretical Basis of Analyses Included
Comparison of Reported and Derived RR and C.I. Values
SAS Programs Used and Outputs
Input Data