Efficacy in Intermittent Iron Supplementation in the Control of Iron Deficiency Anemia in Developing Countries
by George H Beaton and George P McCabe
Review by Eva-Charlotte Ekström, PhD
Scientific Consultant, ICDDR,B, Bangladesh
This is the much awaited report on the collective experience of studies comparing effectiveness of daily vs. intermittent iron supplementation. Studies were undertaken as a response to the so called "mucosal-block -theory". The theory was developed from two studies on rats, showing that administration of iron on an intermittent basis could yield net absorption as great as, or greater than, daily dosing. The hypothesis was that after intake of first supplements the intestinal mucosa would be blocked for absorption of subsequent iron supplements. By timing supplementation frequency to mucosal turnover a larger efficacy might be achieved.
The "mucosal-block-theory" appeared at a time when poor effectiveness of iron supplementation programmes was much discussed. One of the major reasons suggested for poor effectiveness was proposed to be the pregnant women's limited compliance. This in turn was explained by the side-effects that iron supplements may produce. An intermittent dose-schedule was thus hypothesized to both improve compliance (fewer tablets to be taken and less problems with side-effects) as well as efficacy per dose of iron taken.
The mucosal-block hypothesis created much interest in the international nutrition community and a large number of studies addressing the theory were undertaken. Thirty trials were identified and the analysis in this report is based on results from 22 completed studies. For 14 of these, complete data sets were made available for pooled analyses. The others contributed to a meta-analysis.
The report compares weekly and daily supplementation schedules in terms of effect on hemoglobin concentration, anemia prevalence and iron stores. The analyses are divided into three population groups, pregnant women, adolescents and school children, and pre-school children. Only a small difference in hemoglobin concentration was found after supplementation. The overall estimated difference was 2.17 g/L. This difference is smaller than the proposed level of 5 g/L as the smallest difference of biologic importance set by INACG in 1984. However, it is interesting to notice that this small difference in hemoglobin concentration corresponded with a significant increased risk of anemia in the weekly group. A relative risk of 1.34 (Cl 1.20-1.49) was found. Examining the different population groups separately a statistically significant increased risk of anemia was found for pregnant women (RR 1.29, Cl 1.10-1.51) and for adolescents and school children (RR 1.44, Cl 1.33-1.56) but not among pre-school children (RR 1.06; Cl 0.84-1.34).
Interestingly, it appears that degree of "control" of supplement intake was associated with absolute impact on anemia. It is hardly surprising that in studies where tablet intakes were supervised or "under control" a larger absolute impact on anemia was observed. Low compliance has been proposed as one of the reasons for limited effectiveness of programmes to reduce anemia prevalence. The pooled analyses provide evidence to support this hypothesis. While level of supervision had little effect on relative efficacy among pregnant women, it appeared that under highly controlled conditions among adolescents and school children the impact of weekly approached that of daily supplementation.
The authors conclude that both of the treatments are efficacious but weekly supplementation is likely to be less effective except in situations where supervision is feasible with weekly but not with daily. Weekly supplementation is particularly disadvantageous during pregnancy and in situations where the prevalence of anemia is high. The authors recommend that daily supplementation should continue to be the recommended dose frequency for pregnant women. For adolescents, school and preschool children weekly supplementation should only be used where a high level of compliance may be assured.
The report is interesting and comprehensive, both in describing the background for the studies as well as in analyzing the data and in interpreting them. The discussion offers insight into most of the current issues related to anemia control. The statistical approaches used are exhaustive. However, a public health based analysis of potential importance was found missing. While the distinction between prevention and treatment is frequently mentioned, no comparison is made between weekly and daily supplementation in their effectiveness in preventing anemia among initially non-anemic individuals, and their effectiveness in treating anemia among initially anemic individuals. However, a comparison between prevention and curative effectiveness would only be meaningful if screening and application of different treatment alternatives for anemic and non-anemic individuals are considered in programmes. This may not be the case in most low-income countries.
While the rationale to define "efficacy" as the "maximum achievable effect under research or ideal condition", and "effectiveness" as "how well can the beneficial effect be achieved under normal (non research) conditions" is an understandable effort to make it clear that the report may not predict programme effectiveness, it may add to the confusion. The reason is that the trials were, as spelled out by the authors, of mixed designs. In the supervised trials the observed effect is only due to biologic factors, i.e., truly optimal conditions (high compliance), and thus efficacy trials. However, the other trials are of intent-to-treat design and the final effect is both influenced by biologic factors and behavioral factors (compliance): effectiveness trials. Without differentiating between biologic effect and effect of compliance it is difficult to evaluate the mucosal-block-theory. Furthermore, for programmes, it is important to distinguish limitations in efficacy from that of effectiveness as they imply different actions. To make the necessary differentiation between effectiveness in programmes from that in research, "programme effectiveness" could be used.
The authors conclude that the mucosa-block-theory is flawed. It is important to recognize other merits of the theory. Maybe its greatest contribution has been to draw attention to iron supplementation and initiate renewed efforts in advancements towards the prevention and control of iron deficiency anemia.
ISBN 1-894217-08-X published by Ml (1999), 138pp, US$20.00, available from IDRC, PO Box 8500, Ottawa, Canada K1G 3H9; or order from the Web <http://www.idrc.ca/booktique>
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Agricultural Biotechnology and the Poor An International Conference on Biotechnology Edited by GJ Persley and MM Lantin Convened by the Consultative Group on International Agricultural Research and the US National Academy of Sciences This conference, held in October 1999, responded to the
pressing need for an open, inclusive, and participatory debate on potential
benefits and risks of biotechnology, grounded in scientific evidence, and
concerned with the common good. The proceedings document these science-based
discussions on the topics of controlling environmental risks, minimizing health
risks, minimizing social risks, ethics and biotechnology, intellectual property
rights, public concerns, and public/private research. An entire section analyzes
the opportunities and constraints for agricultural biotechnology in China,
India, the Philippines, Thailand, Brazil, Costa Rica, Mexico, Egypt, Iran,
Jordan, Kenya, South Africa and Zimbabwe. This 234 page book is available
from: Consultative Group on International Agricultural Research, 1818 H St NW,
Washington DC 20433 USA, or check the website:
<http://www.cgiar.org/biotechc/bioconf.htm> |
The World Health Report 2000
Health Systems: Improving Performance
WHO has performed an expert analysis of the increasingly important influence of health systems in the daily lives of people worldwide. Health systems provide the critical interface between life-saving, life-enhancing interventions and the people who need them. If health systems are weak, the power of these interventions is likewise weakened, or even lost. Health systems thus deserve the highest priority in any efforts to improve health or ensure that resources are wisely used. This report aims to stimulate a vigorous debate about better ways of measuring health system performance and thus finding a successful new direction for health systems to follow. WHO hopes to help policy-makers weigh the many complex issues involved, examine their options and make wise choices.
ISBN 92 4 156198 X WHO, Geneva, -US $10.20, developing countries ~US$7.15; order from <bookorders@who.int> or view the full report <www.who.int/whr>
The Progress of Nations 2000
This publication records the world's progress towards giving all children the chance to live a life of dignity and opportunity. It captures the slow but steady progress girls and women make as they overcome inequality and discrimination. It also records the devastating speed with which HIV/AIDS has become the greatest catastrophe facing Africa and the rest of the world. This issue celebrates the power of immunization and sets out a new agenda for vaccines. The final chapter reports global statistical profiles which continue to show great disparities between countries. This publication seeks to put an end to the intolerable inequities which exist by exposing them to the conscience of the world community.
Contact: UNICEF, Div of Communication, 3 UN Plaza, NY NY 10017 USA; Email <pubdoc@unicef.org>
Human Development Report 2000
Support for human rights has always been integral to the mission of the United Nations. This Human Development Report 2000 is about human rights and human development. It clearly underlines the fact that human rights are not a reward of development but that they are critical to achieving it. The report cites and examines many examples of egregious human rights violations across the world. It is not aimed, however, at producing legalistic rankings of the worst offenders; it is intended to help promote practical action that puts a human rights-based approach to human development and poverty eradication firmly on the global agenda.
ISBN 0 19 521679.2 UNDP, 1 UN Plaza, NY NY 10017 USA; order from UN Publications, Rm DC2-853, Dept D099; Phone: 800 253 9646; Email: <publications@un.org>; Web: <http://www.un.org/Publications>
Complementary Feeding: Family foods for breastfeed children
This document provides a practical guide to the introduction of complementary foods into the diets of breastfeed children aged 6-24 months. Addressed to health workers in developing countries, the book translates the latest scientific knowledge into clear and simple messages suitable for use when counselling families and communities. Major emphasis is placed on the preparation of foods that are clean, safe, and nutritionally adequate for healthy growth and development. Using a question-and-answer approach, information in the book ranges from diagrams showing the energy, protein, and micronutrient needs of young children, through discussion of the nutrient value of common foods, to recipes for preparing nutritionally adequate meals based on local staples.
WHO/NHD/00.1, WHO Geneva, Dept of Nutrition for Health and Development, 20 Avenue Appia, CH-1211, Geneva 27 Switzerland; Web: <http://www.who.int>
Nutrition in South-East Asia
A comprehensive nutrition profile has been assembled for the WHO South East-Asia Region. This book examines nutrition indicators specific to this Region and their shift over a period of time. The information presented is derived from eight inter-country meetings on nutrition conducted in the Region during 1995-99 as well as various national and international sources. This profile highlights the achievements, constraints, as well as the challenges and the actions required for future nutritional strategies in the countries of WHO/SEARO. It is hoped that Member countries may revise their programmes and prioritize and implement their National Plans of Action for Nutrition at the beginning of the 21st Century in line with the declaration of the 1992 International Conference on Nutrition.
SEA-NUT-148 WHO (2000), Regional Office South-East Asia, Indraprastha Estate, New Delhi 110002, India; Web: <http://www.who.int>
Prevention and Control of Iron Deficiency Anaemia in Women and Children
This document is based on the presentations, discussions and background papers presented during the UNICEF/WHO Regional Consultation on the Prevention and Control of Iron Deficiency Anaemia in Women and Children held in Geneva on 3-5 February 1999. The report contains seven main sections which includes information on the nature of and general prevalence of iron deficiency anaemia globally, and more specifically, on the situation in the countries of Central and Eastern Europe (CEE), the Commonwealth of Independent States (CIS) and the Baltic region. It outlines the causes and consequences of iron deficiency anaemia relevant to pregnant women, women of childbearing age and children less than two years of age. The report emphasizes the need and rationale behind an integrated strategy for control and prevention using multiple interventions such as improved young child feeding practices, dietary education, fortification, supplementation, infection control, monitoring and linkage to other programmes. An entire section is dedicated to the importance, relevance and potential of wheat flour fortification to make a major contribution in reducing iron deficiency/iron deficiency anaemia. Recommendations for the CEE/CIS Region are clearly outlined in the report.
UNICEF (1999) Div of Communication, 3 United Nations Plaza, H-9F, NY NY 10017 USA; Email: <pubdoc@unicef.org> Web: <www.unicef.org>
Anemia Testing Manual for Population-Based Surveys
by A. Sharmanov
This manual was prepared under the auspices of the MEASURE DHS+ project (funded by USAID) which assists developing countries in the collection and use of data to monitor and evaluate trends in population, health and nutrition. The main objectives of MEASURE DHS+ are to provide decision-makers with information useful for informed policy choices; to expand the international population and health database; to advance survey methodology; and to build capacity for high-quality demographic and health surveys. Experiences in anaemia-testing training are summarized in this manual. It is written primarily for health investigators and lays out a standardized approach for hemoglobin testing using the HemoCue system. Particular attention is paid to biohazardous waste disposal and safety precautions when taking blood. Descriptions of the protocols for hemoglobin testing and biohazardous waste disposal are illustrated with colour photos of the procedures. Following the standardized protocols and guidelines presented in this manual could help in collecting accurate population-based data on anaemia prevalence, as well as ensuring protection of human subjects from blood-borne infections and other biohazards.
Macro International Inc, 11785 Beltsville Dr Ste 300, Calverton MD 20705 USA; Phone: 301 572 0200; Fax: 301 572 0999; Email: <reports@macroint.com; Web: <http://www.macroint.com/dhs/>
REPORT on the Global HIV/AIDS
Epidemic - June 2000
This report sets out our current level of knowledge about the epidemic at the start of the 21st century. There is now compelling evidence that the trend in HIV infection will have a profound impact on future rates of infant, child and maternal mortality, life expectancy and economic growth. It demonstrates that lowering incidence and mitigating the epidemic's impacts must be a nationally driven agenda. The report describes other vital elements proved to be successful such as social openness, countering stigma and the engagement of all sectors. Estimates in 1991 predicted that by the end of the decade in Sub-Saharan Africa, 9 million people would be infected and 5 million would die - it was a threefold underestimation. Countries that have adopted forward-looking strategies to fight the epidemic are reaping the rewards in the form of falling incidence.
ISBN: 92 9173 000 9 UNAIDS/00.13E (2000), UNAIDS, 20 Avenue Appia, 1211 Geneva 27 Switzerland; Phone: +41 22 791 4651; Fax: +41 22 791 4165; Email: <unaids@unaids.org; Web: <http://www.unaids.org>
Overcoming Child Malnutrition in Developing Countries
Past Achievements & Future Choices by L Smith & L Haddad
In order to reduce malnutrition, one must understand its complex and interrelated causes. They range from factors as broad as political instability to those as specific as diarrhoeal disease. Policymakers and researchers endlessly debate which of the many causes of malnutrition are most important, and which areas of intervention will be most successful in reducing it. This IFPRI 2020 Discussion Paper No. 30 stresses that any comprehensive strategy for resolving the problem of child malnutrition must include actions to address both its underlying and basic causes. The study employs nationally representative data on child underweight from the period 1970-1995 to undertake cross-country regression analysis of the determinants of child malnutrition. The study's purpose is to determine which of the various broad determinants of child malnutrition are most important in each region of the developing world. The report also aims to unravel the answers to a number of puzzling questions currently under debate: 1) Why has child malnutrition been rising in Sub-Saharan Africa? 2) Why are child malnutrition rates in South Asia so much higher than those in Sub-Saharan Africa? 3) How important a determinant of child malnutrition is food availability at a national level? 4) How important are women's status and education? 5) How important are national political factors and income, and through which pathways do they affect child malnutrition? Addressing these questions should help policymakers direct resources effectively to reduce child malnutrition as quickly as possible.
Contact Bonnie McClafferty at <B. McClaffertv@CGIAR.ORG >or see <http:// www.cgiar.org/ifpri/pubs/catalog.htm#top>. Also see Explaining Malnutrition in Developing Countries: A Cross-Country Analysis by L Smith & L Haddad. Research Report No. 111 (Washington DC: IFPRI, 2000).
Best Practices and Lessons Learned for Sustainable Community Nutrition Programming
By KS Ndure, MN Sy, M Ntiru, and SM Diène
The unique feature of this document is that from beginning to end, it presents lessons learned from diverse African experiences: basic elements, effective strategies, and necessary steps to sustainable community nutrition programming. Successful interventions are conceived of and implemented in a decentralized manner, centering around the community and encouraging community participation in every step of planning, implementation and decision-making. Carefully linking interventions with other development sectors can lead to positive outcomes. This document includes a practical, five-step approach to establishing community nutrition programmes. It provides guidance for improving effectiveness and suggests ways that governmental and NGO actors can collaborate effectively. This document would be useful for programme planners and managers, central and district level nutritionists, and funding agencies.
Contact: AED, SARA/SANA, 1875 Connecticut Ave NW, Washington DC 20010 USA; Phone: 202 884 8815; Fax: 202 884 8400; Email: <mntiru@smtp.aed.org>
Intensifying Action against HIV/ AIDS in Africa
The World Bank details its strategic plan in the fight against HIV/AIDS in Africa in this document. To stimulate and support implementation of the strategy, the Bank has established a multisectoral AIDS Campaign Team for Africa. The team will provide a variety of services including: equipping and supporting Bank country teams to mobilize African leaders and other sectors to intensify action against HIV/AIDS; and retrofitting projects with HIV/AIDS components where possible. The team also plans to explore the feasibility of building an AIDS impact assessment module into existing environmental and/or social assessment processes; and to collect and disseminate information on the progress of the epidemics, country-by-country statistics, and best practices. It is expected that the Bank's partnership with UNAIDS will be strengthened and expanded, as well as its partnerships with other key agencies, NGOs and bilaterals.
The International Bank for Reconstruction and Development/The World Bank (2000) Office of the Publisher, 1818 H St NW, Washington DC 20433 USA; Fax: 202 522 2422.
