Tackling Moderate Malnutrition: The Next Frontier

TACKLING MODERATE MALNUTRITION: THE NEXT FRONTIER Malnutrition kills. Not too startling a statement, yet only a decade ago, few child-health experts appreciated that the majority of childhood deaths in the developing world were the result of the interactive effect of malnutrition and infectious diseases. Today, few remain incognizant of the link, and the subject of severe malnutrition has appropriately been the focus of much recent international attention, resulting in improved understanding of the problem, new approaches being developed and tested, and stronger partnerships being established (1,2). However, many child health practitioners remain oblivious to one key fact: more than 83% of malnutrition-related deaths are the consequence of mild-to-moderate rather than severe malnutrition (3). Strategies involving only the screening and treatment of the severely malnourished will do little to address this problem. Children who are mildly underweight (Z score between −1 and −2) have about a two-fold higher risk of death than do those who are better nourished. This risk increases to fivefold to eightfold in moderately (Z scores between −2 and −3) to severely (Z score < −3) underweight children (4). These children betray no outward signs of malnutrition to the casual observer and thus are frequently ignored or missed by health services, aid agencies and development programs. In this issue of the Journal, an article by Maleta et al. (5) is a valuable addition to the scant literature specifically examining interventions involving food supplementation for moderately malnourished children. In a randomized trial of moderately malnourished children, maize and soy flour (an indigenous diet) were compared to ready-to-use food (RTUF) in a 3-month, home-treatment program. Both of their main conclusions, while not unexpected, are important and worthy of further deliberation. First, both supplements resulted in modest weight gain, but the effects lasted longer after RTUF supplementation; and second, despite providing supplements at no cost to participants and delivering them to the home, less than half of both supplements were consumed by the children. Commercial supplementary foods have been studied previously and have generally had a favorable influence on growth. The intervention used in this study, a recently developed spread (the RTUF) has attractive qualities. It has a very high energy density (23 kJ/g), is micronutrient fortified, does not need to be cooked before consumption, has excellent storage (bacteriostatic) properties, and importantly, is considered palatable by children (6). It has been successfully used at therapeutic feeding centers and in emergency relief situations. Two major disadvantages are its limited availability and its cost. However, even these constraints have been successfully overcome in a Malawian setting similar to the one in which the study by Maleta et al. was conducted. An almost identical RTUF, with similar anthropometric and health benefits, was produced locally at about a third of the cost of the imported product (7). The improved weight gain in the RTUF group for three months after the supplementation period ended is somewhat puzzling. The researchers' hypothesis that the children may have had a better appetite as a consequence of the correction of micronutrient deficiency is plausible but was not confirmed in a Beninese study (8) and requires further investigation. The lack of a significant effect on linear growth can be explained by the relatively short duration of the trial. Because weight responds faster to intervention than does length, a longer period might have resulted in detectable differences. The poor consumption of the supplements provided at no cost is of concern, but the phenomenon has been described in previous studies. In one study of growth retarded children whose energy intake did not meet requirements, as much as 25% of food offered was not consumed (9). The researchers attribute the poor compliance noted during the fortnightly 24-hour recall to possible “domestic diversion” or the premature exhaustion of supplies. The relative roles of morbidity-induced anorexia, micronutrient deficiency, and palatability in the appetite of young children are not known. It is well known that zinc deficiency depresses appetite, and the same may be true for other nutrient deficiencies. Improving dietary quality, rather than quantity, may be key to successful supplementary food diets. Further, the findings support the argument that although poverty may be the chief contributor to malnutrition, the problem should be seen as poor health, rather than simply low food consumption. The reduced consumption of staple foods when supplementary or complementary foods are provided is also a recognized consequence of supplementation programs. Previous studies have shown reduction in consumption of usual foods as a result of supplementation (10,11). The accelerated weight gain noted in the study, despite the apparent lack of increase in energy intake, points to a possible underestimation of intake by the 24-hour recall method. It is noteworthy that staple food intake was not compromised in the RTUF group, signifying that RTUF was viewed as a supplement, rather than a “food,” probably because of its small volume and ready-to-use design The study has several limitations. The small sample size limits its ability to identify significant differences between the two intervention arms. Its dependence on two-weekly, 24-hour dietary recalls seriously compromises the validity of the compliance data. The human immunodeficiency virus (HIV) status of the children was undetermined. In this setting, it would not be unexpected that at least a quarter to a third of childhood undernutrition could be associated with HIV, thus undermining the potential benefit of food supplementation (7). The study also concentrated on children older (42–60 months) than those at highest risk of malnutrition (6–24 months). It is expected that nutritional gains from food supplementation would be less marked in the age group studied here (12). The focus on technological interventions, such as the use of RTUF in this study, as a solution to what is fundamentally a geopolitical and socioeconomic problem continues to be a valid criticism of scientific work in this area. In defense, although more vigorous and enthusiastic attention to distal determinants such as poverty, the physical environment, poor literacy, inequities in food security, and ailing health systems is critical, identifying feasible and sustainable short- and medium-term solutions to the more proximal determinants of child malnutrition, and particularly those that can be delivered through the health sector, remains equally important. The traditional biomedical approach to the management of moderate malnutrition depends primarily on an assessment of feeding practices and the provision of feeding advice, both of which are time-consuming and for which there is limited evidence of efficacy. Recent studies from China (providing culturally appropriate nutrition education) (13) and Brazil (use of modified Integrated Management of Childhood Illness [IMCI] nutrition counseling guidelines) (14) indicate that more focused nutritional counseling and training can influence the diet and growth of children, partly by improving maternal knowledge, infant feeding practices and physician performance. A number of factors interfere with the success of nutrition counseling, including the intensity of intervention, the complexity of behaviors to be changed, timing considerations, and the existence of external constraints such as low food availability. It is likely that interventions targeted at the entire community, rather than at individual mothers, will have more impact (15). The value of food supplementation compared with nutritional counseling alone or in combination has yielded conflicting results. Can or should Maleta et al's study findings be applied more widely? There are many obstacles to effectively scaling up the successful experience of small-scale local projects such as this one. These include identifying eligible children, funding the program, and ensuring efficient and effective delivery of the intervention. A recent technical meeting deliberated in detail on the development of new approaches to providing complementary food supplements designed to achieve micronutrient adequacy in infants and young children (16). Age and anthropometric criteria are often used to select children for supplementary feeding programs in populations similar to the one in this study. Validation of the anthropometric screen to define and measure moderate malnutrition is an area that requires further development. In most populations with mild to moderate malnutrition, death as the outcome to be prevented probably is better proxied by children with stunting than those with wasting (which is a more useful indicator of severe malnutrition). Rather than using risk screens for a deleterious outcome such as death, the most useful screen would identify children who would predictably benefit most from the nutrition and other interventions proposed (17). The authors have not addressed cost-benefit or effectiveness issues in the article. Implementation of new strategies such as RTUF cannot be undertaken without more resources devoted to health care. External donor funding is an oft-touted solution but may not be forthcoming. The European Union and the United States pledged to reverse years of declining aid to developing countries when they promised an extra $12 billion for development at the 2002 United Nations summit in Monterrey, Mexico. Despite this, the United States is proposing to spend one-third less on international maternal and child health in the next federal budget (18). Finally, are efforts better directed at preventing moderate malnutrition rather than its treatment? There is insufficient evidence to answer this question. In Guatemala, supplementary feeding of children aged 6 to 24 months in populations with inadequate dietary intakes prevented the onset of wasting in a large proportion of children (19). Four Brazilian nutrition programs were more effective at curing, than at preventing, malnutrition and were better at improving weight than height (20). Depending on the resources available, the cost of screening, and other considerations, a feeding program for all children 6 to 24 months of age might be preferable, rather than selecting a subgroup for supplementation. A possible argument against universal supplementation is that children in the upper range of the weight-for-length distribution who receive supplements might become obese. In 2002, as part of the development of health goals for the millennium, all 189 United Nations member nations pledged to ensure a two-thirds reduction in child mortality, a halving of global hunger, and a one-third decrease in malnutrition among children younger than 5 years of age, by the year 2015 (21). Biological, behavioral, and health system interventions tackling moderate malnutrition are critical to achieving these lofty goals. Is it foolhardy to hope that new research agendas directly involved in determining, implementing and evaluating solutions to the problem will attract an enthusiastic response from national and international sponsors?