Globally, low birth weight (LBW) is a major factor contributing to stunting, the most common form of childhood malnutrition. Both LBW and stunting are associated with substantial mortality and disease burden. To reduce the burden of LBW and stunting, national governments should play effective roles through multisectoral collaboration, with strong political commitment to ensure nationwide coverage of direct or nutrition-specific interventions and indirect or nutrition-sensitive interventions. The former include interventions such as breast-feeding, complementary feeding, micronutrient supplementation, treatment of acute malnutrition, and the like. Indirect interventions include improving agricultural crop yield as well as food diversity, creating livelihoods, increasing literacy, and empowering women, and so on.
There is no single remedy for stunting; comprehensive implementation of basic nutrition interventions should reduce the burden of stunting. Severe acute malnutrition (SAM) kills 1 million children each year in 20 countries across Africa, Asia, western Pacific, and the Middle East. Facility-based treatment is available in some countries but is expensive and inconvenient to family as it requires lengthy hospitalizations and its outreach is limited. Community-based management of SAM can complement facility-based treatment by expanding the outreach, curtailing facility expenses, and allowing treatment at home, thereby decreasing the burden on families. This, however, has to be tagged with interventions that prevent malnutrition. The prevalence of childhood obesity is rapidly growing in developing countries and is a priority requiring action. Finally, applied research should focus on the effectiveness of intervention strategies, whereas basic research is required in the interaction between nutrition and human microbiome, and conditions such as environmental enteropathy (EE).
SUMMARY OF THE PROBLEM
The term malnutrition refers to both undernutrition and overnutrition. Undernutrition encompasses intrauterine growth retardation (IUGR), protein-energy malnutrition, and deficiency of micronutrients, including essential vitamins and minerals (1), whereas overnutrition encompasses overweight and obesity. Undernutrition kills or disables millions of children every year, and prevents millions more from reaching their full intellectual and productive potential. Globally, stunting and LBW are 2 major manifestations of childhood undernutrition. Women who were stunted as girls, whose nutritional status was poor when they conceived, or who did not gain enough weight during pregnancy may give birth to babies with LBW, which predisposes infants to stunting (2). Stunting in the first 2 years of life leads to irreversible damage, including shorter adult height, lower attained schooling, and reduced adult income (3), resulting in financial burdens worldwide. Stunting and LBW together are responsible for 2.1 million deaths (21% of worldwide deaths in under-5 children and 91 million disability-adjusted life years [DALYs], which is 21% of global DALYs for under-5 children and 7% of global total DALYs) (4). Again, SAM affects approximately 20 million children younger than 5 years and contributes to >1 million child deaths in the world each year with the majority of deaths occurring in 20 countries across 4 regions: Africa, Asia, western Pacific, and the Middle East. The high mortality and disease burden resulting from these nutritional disorders make a compelling case for the urgent implementation of effective interventions. The interventions targeting undernutrition need to be scaled up to cover at least 70% of the total population to show tangible outcomes (5). For example, facility-based treatment of SAM is available in some countries but is expensive and inconvenient to the family as it requires lengthy hospitalizations, and its outreach is limited. Community-based management of SAM can complement facility-based treatment by expanding the outreach, limiting facility expenses, and allowing treatment at home, thereby decreasing the burden on families. On the contrary, effective interventions are still not available for intrauterine IUGR and stunting, conditions that affect >20% of all under-5 children. In spite of some efforts at the global and country levels, changes in rates of childhood undernutrition status are minimal. It is now imperative to look for novel evidence-based interventions for undernutrition. Because education is the key part of every intervention, we also need to equip health care providers with the knowledge and skills to screen, diagnose, and manage undernutrition by developing and implementing integrated training courses.
Obesity, on the contrary, has become a global public health priority given its increasing prevalence throughout the world and effect on the health of the individual and the economic costs associated with it. The risk factors for obesity are many and involve genetic, metabolic, behavioral, environmental, and cultural causes. The interplay of these factors is complex and has been the focus of considerable research; however, the burden of obesity is not experienced uniformly across a population, with the highest levels of the condition experienced by those most disadvantaged. The best intervention is the implementation of preventive measures that target populations in addition to the at-risk subgroups. Education is one of the major factors for reducing the burden of obesity; change in behavior through effective counseling of children, parents, teachers, community leaders, and health care professionals is important. FISPGHAN Working Group members defined a set of priority actions for controlling childhood malnutrition focusing on medical interventions, education, and research (Table 1).
Priority 1: Intervention—Scaling up Basic Nutrition Interventions to Reduce Low Birth Weight and Stunting
Stunting, which reflects chronic nutritional deficiency, is defined as height-for-age 2 standard deviations below the median height of the standard reference population (2). Among under-5 children in the developing world, an estimated one-third (or 195 million children) are stunted, whereas 129 million are underweight (weight-for-age 2 standard deviations below the median weight). Twenty-four countries bear 80% of the global burden of undernutrition as manifested by stunting.
About 30 million babies are born annually with a low birth weight (<2500 g). This is 24% of all births. LBW is a principal determinant of morbidity, mortality, disability during childhood, and long-term health outcomes. A recent community-based Bangladeshi study reveals that LBW infants had significantly lower mental and psychomotor developments and were less active than infants born with normal birth weight (6). Interventions that affect reduction of LBW need to be scaled up. They include, among others, dietary adequacy, rest and stress alleviation during pregnancy, iron-folic acid supplementation, and the like. During scaling up, it is often necessary to prioritize population groups that have a more urgent need, that is, the most undernourished children, given resource constraints (7). These groups—often the most undernourished—usually fall outside the reach of public programs or private-sector marketing owing to factors such as geographical isolation, gender inequality, low purchasing power, social exclusion, and illiteracy. Strategies, intervention programs, and campaigns should therefore be tailored to reach the hardest to reach. In 2008, the Lancet series on maternal and child undernutrition clearly identified evidence-based ready to scale up basic nutrition interventions that have proven effectiveness in combating undernutrition in countries with high nutrition burden (5). Priority interventions include the following:
1. Breast-feeding promotion: Early and exclusive breast-feeding (EBF) is an important intervention of proven efficacy that reduces neonatal, infant, and child mortality, and remains a basis for child survival strategies. As much as 13% of all global deaths of children younger than 5 years can be prevented through breast-feeding promotion (8). A recent multicountry review shows that effective breast-feeding promotion interventions can significantly increase EBF rates up to 6-fold in developing and 1.3-fold in developed countries, respectively (9). Effective programs of education, counseling, and support are considered necessary not only to promote breast-feeding but also to prolong the duration of EBF to up to 6 months of age.
2. Appropriate complementary feeding: The period from birth to 2 years of age is well recognized as the critical window for the promotion of optimal growth, health, and development. Even with optimum breast-feeding, children become stunted if they do not receive sufficient quantities of quality complementary foods after 6 months of age (4). A global estimate indicated that about 33% of children ages 6 to 23 months receive optimal complementary feeding (10) in terms of amount, frequency, and consistency of diet (Fig. 1).
3. Supplementation with essential vitamins and minerals: Vitamin A deficiency in newborn babies, infants, and children accounts for approximately 6% of under-5 deaths, 5% of under-5 DALYs, and 1.7% of total DALYs lost. Zinc deficiency accounts for approximately 4% of under-5 deaths and DALYs, and 1% of total DALYs lost (4). Vitamin A supplementation can reduce all-cause mortality for children 6 to 59 months by 23%, and several studies suggest that therapeutic zinc supplements for diarrhea can reduce diarrheal mortality below the age of 5 years by 50% (11). Approximately 41 million newborns each year remain unprotected from the serious consequences of brain damage associated with iodine deficiency (2), which could be easily prevented by ensuring that salt consumed by household members is adequately iodized.
4. Appropriate management of SAM: Application of the WHO protocol for management of SAM could reduce the number of deaths by 55%, and prevent 152,000 deaths in hospitals or health facilities equivalent to averting 5 million DALYs (12). To achieve this reduction, all children at high risk for death from SAM would need to reach a health facility capable of delivering the WHO protocol; however, few children with SAM can actually be treated in a hospital setting because of lack of beds, time, and cost taken for the travel to a hospital, and others. In countries that have a high burden of acute malnutrition, there should be interventions on community-based management of acute malnutrition (CMAM).
5. Sanitation and hygiene interventions: Gastrointestinal infections such as diarrhea adversely affect nutritional status, whereas malnutrition can predispose to infections such as diarrhea. Approximately 88% of all cases of diarrhea globally are attributable to unsafe water, poor sanitation, and hygiene; such high rate of diarrhea, along with stunting, can be reduced by sanitation and hygiene interventions (13). These interventions are also believed to reduce EE—a condition caused by chronic exposure to pathogens that colonize the small intestine resulting in villous damage, malabsorption of nutrients, and malnutrition (14).
Priority 1: Education
The past decade has seen a reduction in the number of training courses on management of acute malnutrition. This is partly as a result of the lack of emphasis and partly because of the confusion created between facility-based and CMAM. It is extremely important that the World Health Organization manual on management of severe malnutrition be revised on the basis of recent evidence to include both facility- and community-based management and management of infants younger than 6 months and experiencing SAM. Comprehensive training course curriculum and method should be developed combining facility and community-based management, and training courses rolled out in Asia and Africa.
Priority 1: Research
1. Resource constraints do not allow many countries to scale up nutrition interventions. Bundling of several evidence-based nutrition interventions may be cost-effective, but this has to be evaluated through research.
2. The community health worker (CHW) is the contact for providing knowledge to the mothers. In many countries, the quality of counseling is poor and this is largely believed to be because of inadequate numbers of CHW and poor motivation. What should be the optimum and practically feasible number of CHWs and how should their motivation and commitment be improved? Is volunteerism an option? These are important questions that can be answered by operations research.
3. Stunting is attributed to be responsible for 14% deaths among under-5 children. Yet there is no solution for it. Based on a critical analysis of determinants of stunting, intervention(s) should be designed to treat this pervasive manifestation of malnutrition.
4. The negative affect of stunting persisting after 2 to 3 years of age on cognition are considered irreversible. However, there is a need for research to find optimum management of older children who are stunted.
Priority 2: Implement CMAM in High-burden Regions
SAM is defined by any of the following: the presence of weight-for-height below minus 3 standard deviations from the median weight of the standard reference population, mid-upper arm circumference (MUAC) <115 mm, visible severe thinness, or the presence of nutritional edema (2,12). An estimated half a million children who are younger than 5 years die each year of SAM, resulting in 6% of DALYs among under-5 children, although other estimates are greater (4,15). Most children with SAM come from resource-poor settings and, thus, cannot be accommodated in hospitals (16). Moreover, many families cannot afford the mothers or any earning members to stay with their children in hospitals for weeks together. Home-based treatment of severely malnourished children provides a feasible solution. The advantages of home- or community-based management include reduced exposure to hospital-acquired infections, increased presence of primary caregiver at home with other siblings, and continuity of care after discharge (17). Treatment of SAM until recently was limited to traditional center-based inpatient care and had limited coverage. Hence, identification of children with SAM in the community along with appropriate referral and management of the less severe cases are important factors in expanding coverage of the treatment of SAM (18). To address this problem, CMAM approach has been designed to identify children with acute malnutrition (SAM, moderate acute malnutrition, defined as weight-for-height between <−2 and −3 or a MUAC <120 mm), refer acutely ill children for management in a stabilization center and managing children with SAM but no complications in the home with ready-to-use therapeutic food (RUTF). When community-based management is properly combined with a facility-based approach, the result is a reduction in the number of deaths down to ∼5% (16).
Countries such as India, Afghanistan, Bangladesh, Uganda, and Sudan have huge burdens of acute childhood malnutrition. India alone is home to >8 million children with SAM. Successful implementation of CMAM is needed to be integrated within other existing child health and nutrition services program of high-burden countries. Four primary components of CMAM should be considered for effective implementation in communities (19).
1. Community mobilization: An ongoing community awareness creating process involves assessing community capacity, community sensitization, identification of malnourished children with proper referral, follow-up care of malnourished children, and laying the foundation for community ownership (19).
2. Supplementary feeding program: Supplementary feeding is the distribution of food to supplement energy and other nutrients missing from the diet of those who have special nutritional requirements and those living in conditions of severe food insecurity (20).
3. Ready-to-use therapeutic food: The key nutritional component of SAM treatment in the community is RUTF, which is a nutrient-dense food with a nutrient content similar to F100, the milk-based liquid formula used in facility-based treatment of SAM (21). RUTF does not contain any water and thus is free of bacterial contamination and can be stored in high ambient temperature and humidity conditions without spoilage.
4. Inpatient care: Acutely malnourished children with medical complications should be taken care of in a hospital or a community health care facility prepared for the adequate treatment of SAM and complications. Evidence from a resource-poor country such as Bangladesh demonstrates that severely malnourished children can be successfully managed (recovery rate of 82%) in a day-care setting, if the staff are adequately trained and required logistic support is available (22).
Priority 2: Education
The curricula and textbooks for medical and nursing students as well as reference pediatric textbooks should be revised to include recent developments in the management of acute malnutrition.
Priority 2: Research
Many countries with a high burden of acute malnutrition are yet to have national CMAM programs. An important reason for the reluctance to have national CMAM programs is the need to import RUTF and its high cost. Imported RUTF is not considered sustainable in nonemergency settings. A recent Zambian study shows that RUTF alone constitutes 36% of the total cost of CMAM (21). An effective solution to this problem would be local production of RUTF. When RUTF is made with locally available food ingredients, it should become readily available, easily accessible, culturally acceptable, and cost-effective. Research is urgently needed to develop recipes of RUTF conforming to international specifications using locally available food ingredients.
CMAM should be tagged with interventions that prevent malnutrition, including food security, infant and young child feeding (IYCF), micronutrient supplementation, deworming, livelihood creation, and water-sanitation-hygiene interventions. The effect of such bundling of interventions, however, needs to be evaluated through robust experiments.
Priority 3: Intervention—Introduce Intervention(s) to Prevent Childhood Overweight and Obesity in High-prevalence Countries
Countries throughout the world are experiencing marked increase in the prevalence of overweight and obesity in children and adolescents (23). Overweight and obesity are defined as body mass index >25 and >30 kg/m2, respectively (24). By 2010, >40% of children in the North American and eastern Mediterranean WHO regions, 38% in Europe, 27% in the western Pacific, and 22% in southeast Asia were predicted to be overweight or obese (25). At the population level, these countries exhibit several obesogenic factors such as ease of access to unhealthy processed foods, cost and access barriers to healthy foods, limited infrastructure for physical activity, high rates of vehicle ownership, and widespread access to television, video games, and computers (26). Obesity rates are also associated with socioeconomic status (25). In developed countries, children from low socioeconomic settings are obese because foods with high fat and high sugar are cheaper, whereas in developing countries, the condition is vice versa. The interplay of these factors is complex and has been the focus of considerable research; however, the burden of obesity is not uniform across a population, with the highest levels of risk in those most disadvantaged. Being overweight and obese in childhood consistently increases the risk of being overweight or obese in adolescence and adulthood thereby contributes to the overall direct and indirect costs of adult obesity. In Canada, obesity-related comorbid conditions alone contribute to a 3-fold rise in annual health care costs (26), whereas in the United States, childhood obesity alone is estimated to cost US$14 billion annually in direct health expenses (27). As the determinants of childhood overweight and obesity are multifactorial (Fig. 2), the intervention strategies should be organized at individual, household, institutional, community, and health care levels (25). Policymakers and education leaders need to consider the affect of childhood obesity on government budgets at all levels over the long term. School- and community-based interventions are warranted to combat the childhood obesity epidemic.
Priority 3: Education
Access to the Internet has increased considerably in Asia and Africa. Because real-life training courses are difficult to organize and can be expensive, Internet-based interactive modules on the management of childhood malnutrition should be developed and promoted.
Priority 3: Research
Recently there has been a resurgence in the interest on EE as a major contributor to childhood malnutrition. EE is a subclinical condition of the small intestine characterized by villous atrophy, crypt hyperplasia, increased permeability, inflammatory cell infiltrate, and malabsorption (14,28). The condition is caused by fecal bacteria ingested by young children living in conditions of poor sanitation and hygiene. It is believed that EE results when T cells in the intestine are hyperstimulated by abnormally high concentrations of ingested fecal bacteria in the small intestinal lumen. It is imperative that EE be identified at the community level using simple but reliable techniques/biomarkers. Such techniques/biomarkers having high sensitivity and specificity will enable estimation of the burden of EE and in finding out appropriate strategies for its control. This will ultimately have a positive effect on child nutritional status.
Experimental and human studies have shown that gut microbiota play an important role in formation of the obesity phenotype. Predominance of either the Firmicutes or the Bacteroidetes phyla in the gut could predict whether individuals on isocaloric diets will become obese or remain lean. Whether the opposite pattern is true for undernutrition remains to be investigated. Should microbiota play a role in the etiology of undernutrition, special diets, prebiotics, or probiotics can be designed to modulate the gut environment to the benefit of the individual child. Single nucleotide polymorphisms have also been detected for the obesity phenotype. With the advent of inexpensive high-throughput sequencing, genome-wide association scan should also be done to see whether a condition such as stunting has a genetic basis.
HOW DO WE ACHIEVE THE GOALS?
Scaling Up Nutrition Interventions to Reduce Low Birth Weight and Stunting
To eliminate stunting and low-birth-weight child from a country in the longer term, basic nutrition interventions should be supplemented by improvements in the underlying determinants of undernutrition, such as poverty, poor education, disease burden, and lack of women's empowerment. Successful and sustainable scale-up of basic nutrition interventions rests on a number of critical factors (7):
1. Government leadership and championship: Strong government leadership not only helps coordinate the efforts of government ministries, but also establishes norms for the private sector that oblige them to participate in and comply with public programs. There should be sustained national efforts dedicated to the process of policy formulation, including agenda setting and commitment building, choice and design of actions, quality of implementation, and adjustment of actions based on monitoring and assessment, and human and institutional capacity building (7).
2. Clear public health policy and law enforcement: Strong government leadership must be supported by public policies and programs that are tailored to reach those who are most in need of nutrition interventions. Legislation is useful, but will not be sufficient without accompanying regulations and enforcement (12).
3. Focusing on appropriately targeted public programs: Even achieving high coverage is not enough if the process of scaling up either systematically excludes the people in need or wastefully misdirects services to those who cannot benefit or are not in need (12). To address this situation, government, policymakers, public health officials, and the private sector must tailor programs and marketing campaigns to the hardest to reach peoples with geographical isolation, gender inequality, low purchasing power, social exclusion, and illiteracy (7).
4. Multisectoral collaboration: As nutrition often falls within the mandate of several ministries/departments, the packages of nutrition interventions need to be implemented in conjunction with relevant health and water/sanitation with clear roles and responsibilities (2).
5. Public-private partnership: The involvement of the private sector can ensure the availability of appropriate and affordable products, such as high-quality foods for complementary feeding and supplementary feeding, and micronutrient-fortified staple foods and supplements (7). With its extensive access to populations, the private sector also has a role in encouraging behavior change that promotes healthy lifestyles and good nutrition.
6. Effective advocacy and communications: Experience shows that effective large-scale communication campaigns and community involvement are key conditions for programs that seek to improve child care and nutrition and promote behavioral change. Regular support and counseling of caregivers at the community level in a comprehensive manner, with messaging on feeding, care, hygiene, and disease prevention and treatment, can lead to positive outcomes (7).
7. Multiyear resource commitment: Scaling up national nutrition interventions requires a significant investment of finances, administration, and human capital. Successful sustainable nutrition program can be ensured through long-term financial resource availability that should come from both the public and private sources, and from domestic as well as external sources (7).
8. Monitoring and feedback mechanisms: Monitoring helps to focus on measure in areas of lower performance (7). To combat this situation strong emphasis should be given on quality implementation of planned activities at the community level with supportive supervision and continuous monitoring and evaluation with feedback mechanisms.
Action against malnutrition is needed more than ever; however, it is not so easy to invest a huge amount of money to combat undernutrition by the resource-constrained countries where 90% of the undernourished children live. An additional US$10.6 billion/year is required from public resources that can successfully prevent >1.1 million child deaths. Indeed, these core interventions offer among the highest rates of return feasible in international development.
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