THE PROBLEM OF ACUTE MALNUTRITION
In 2000, leaders of 189 countries gathered together and adopted the United Nations Millennium Declaration, presenting eight millennium development goals to achieve within 15 years. “Eradicate extreme poverty and hunger” and “reduce child mortality” were two of these targets (United Nations General Assembly, 2000). In 2015, the efforts done worldwide were assessed. Between 1990 and 2015, the number of people living in extreme poverty and the number of undernourished people decreased by half. The same trend was observed for under-5 mortality (United Nations, 2015). Although progresses have been impressive, millions of people still live below the poverty line and suffer from food insecurity and hunger. In September 2015, another meeting with leaders from all around the world took place and resulted in seventeen sustainable development goals (United Nations Development Program, 2015b). Among them, “zero hunger” aims at fostering decrease in hunger and malnutrition rates particularly in children.
DEFINITIONS AND INDICATORS
One way of defining hunger is as an uncomfortable or painful feeling one’s have when he wants food. Another dimension of hunger is considered when talking about world hunger. In that case, hunger relates to the fact of not having enough to eat in order to cover the body energetic requirements (United Nations World Food Program, 2016), estimated for each age group and sex in a joint report of the Food and Agriculture Organization (FAO), World Health Organization (WHO) and United Nations University (UNU) (Food and Agriculture Organization, World Health Organization, & United Nations University, 2001).
Malnutrition is usually used to describe an imbalanced nutrition. It is categorized into overnutrition and undernutrition. Overnutrition won’t be developed here as it is of lesser interest for the present subject. Undernutrition is one consequence of hunger, that is to say of insufficient food intake, or results of an inadequate use by the human body of the eaten food due to illnesses (Action Contre la Faim, 2012). In this thesis, we are focusing on children’s undernutrition, and more precisely on children under 5 years old.
Undernutrition is usually measured by weight-for-age (W/A), height/length-for-age (H/A) and weight-for-height/length (W/H) ratios, respectively corresponding to underweight, chronic malnutrition and acute malnutrition. Z-scores are used to classify the severity of the three above mentioned dimensions of undernutrition (World Health Organization, 2006):
• A ratio superior or equal to -2 standard deviation (SD) of the WHO Child Growth Standard Median represents a normal anthropometry;
• A ratio comprised between -2 and -3 SD of the WHO Child Growth Standard Median corresponds to a moderate type of undernutrition;
• A ratio strictly inferior to -3 SD of the WHO Child Growth Standard Median stands for a severe type of undernutrition.
Chronic malnutrition, also called stunting, results of a slow process over time and is characterized by growth retardation. Stunted children are generally shorter than they should be. Among acute malnutrition, three clinical forms are distinguished (IASC Global Nutrition Cluster, 2011a):
• Marasmus, or wasting, is characterized by a recent and severe weight loss corresponding to fat and muscles reduction. Children suffering from marasmus are emaciated (IASC Global Nutrition Cluster, 2011a). Wasting is the most common form of acute malnutrition. In addition to Z-scores, the mid-upper arm circumference (MUAC) is used to classify wasting in three categories: absence of wasting, moderate acute malnutrition (MAM) and severe acute malnutrition (SAM). A child is considered as suffering from MAM if his/her MUAC is comprised between 115 and 125 mm (Annan, Webb, & Brown, 2014). A MUAC inferior to 115 mm refers to SAM (World Health Organization & United Nations Children Funds, 2009).
• Kwashiorkor is defined by an important loss of muscle mass and the presence of bi-lateral edemas due to water retention. A child suffering from kwashiorkor has a swelled body and may also have skin lesions. The presence of edema is a criteria to categorize kwashiorkor as SAM (IASC Global Nutrition Cluster, 2011a).
• Marasmic kwashiorkor corresponds to wasting with additional edemas. It is also a form of SAM (IASC Global Nutrition Cluster, 2011a).
Stunting and wasting have different prevalence according to the age in children under five years old. Generally, the prevalence of low weight-for-height shows a peak in the second year of life (World Health Organization, 2017), mostly around 12-15 months of age (Victora, de Onis, Hallal, Blossner, & Shrimpton, 2010). In parallel, the prevalence of low height-for-age starts to rise at about three months of age and slows down at around two to three years of age (Victora et al., 2010; World Health Organization, 2017).
Global acute malnutrition (GAM) rate is one possible measure of the nutritional status of a population. It is the sum of MAM and SAM rates (Center of research of Epidemiology of Disasters, 2016). In this thesis, a particular emphasis is put on acute malnutrition, and especially on wasting.
CAUSES OF UNDERNUTRITION
The causes of acute malnutrition, and more globally of undernutrition, are multiple. In 1990, UNICEF developed a conceptual framework and categorized these causes into three levels: basic, underlying and immediate causes (UNICEF, 1990). Ever since, this framework has been used worldwide and endorsed by the humanitarian community. Figure 2 is an adaptation of this framework in the 2008 Lancet Series on Maternal and Child Nutrition (Black, Allen, Bhutta, Caulfield, de Onis, Ezzati, Mathers, & Rivera, 2008).
Two factors are considered as immediate causes of undernutrition: inadequate dietary intake and disease. A child has an inadequate dietary intake when the quantity and/or the quality of food he/she eats don’t correspond to the needs. In terms of quantity, a child may eat less than required for his/her optimal development. The composition of breastmilk and the adequacy of food given to the child with regards to his/her age, especially at food diversification time, are crucial for an adequate food quality. A child may become undernourished if the diet is not balanced or food insufficient. Disease is the second direct cause of undernutrition and forms with this latter a vicious circle (IASC Global Nutrition Cluster, 2011b; Katona & Katona-Apte, 2008; Tomkins & Watson, 1989). Indeed, a child facing illness needs more energy and selected macronutrients and micronutrients to fight infections. As such an adequate energetic intake is required. As far as macronutrients are concerned, protein intake plays a central role to answer an increased need in some particular amino acids (Biolo, Antonione, & De Cicco, 2007; Wijnands, Castermans, Hommen, Meesters, & Poeze, 2015). However, disease usually reduces appetite or sometimes even the ability to eat, leading to inadequate food intake and undernutrition. As a result, muscles and organs don’t receive the necessary energy or molecules for their satisfactory growth and functioning. In parallel, malabsorption of essentials micronutrients may occur especially when intestinal infections appear. Successive intestinal infections in young children lead to chronic intestinal dysfunction, ultimately leading to undernutrition (Guerrant, Oria, Moore, Oria, & Lima, 2008; Prentice et al., 2008). The whole situation results in increased vulnerability to infections and new episodes of disease. The vicious circle begins again. The most frequent illnesses associated with undernutrition are diarrhea, measles, malaria, acute respiratory infections, intestinal parasites and acquired immune deficiency syndrome (AIDS) (IASC Global Nutrition Cluster, 2011b; Tomkins & Watson, 1989).
Among the underlying causes of undernutrition, poverty has a central role (Black, Allen, Bhutta, Caulfield, de Onis, Ezzati, Mathers, & Rivera, 2008). Poverty is not only a lack of revenue, but also takes into account the available assets and land of the households. Poverty often results in household food insecurity, inadequate care and unhealthy environment, the three key underlying causes of undernutrition.
Food security exists “when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life.” (Food and Agriculture Organization, 1996) It embraces four dimensions: food availability, access, utilization and stability (J. L. Leroy, Ruel, Frongillo, Harris, & Ballard, 2015). Food availability refers to the presence of food in markets or in household’s stock, from the family’s own production. In this regard, agricultural and livestock farming practices have a major role in the quantity and quality of available food within the household. Food access is conditioned upon having enough resources (generally cash) to get appropriate foods for a nutritious diet (Food and Agriculture Organization, 2006). Food use is the adequate utilization of food based on knowledge of nutrition, care, water and sanitation. How the meal is prepared and cooked is particularly important for the quality of micronutrients in the food. Food stability refers to the stability of the three above mentioned dimensions over time. Household food insecurity is due to the absence of one or several of these dimensions and is responsible for an inadequate dietary intake. Positive associations were shown between food security and children’s anthropometry (Abdurahman, Mirzaei, Dorosty, Rahimiforoushani, & Kedir, 2016; Saha et al., 2009).
The second major underlying cause of undernutrition is inadequate care. “Care is the provision […] of time, attention, and support to meet the physical, mental, and social needs of the growing child and other household members.” (Patrice L. Engle, Menon, & Haddad, 1997) Proper daregiving practices include exclusive breastfeeding during the first six months of life of the baby, a step-by-step food diversification and the child stimulation, all playing a major role in the child’s nutritional status (Bentley, Wasser, & Creed-Kanashiro, 2011; Lamichhane et al., 2016; Scherbaum & Srour, 2016). Adequate care requires that the caregiver has sufficient time to dedicate to her/his child, but also that she/he has the possibility to take decision regarding child’s care. The concept of care also refers to mother and child’s mental health and psychosocial well-being, two important determinants of their nutritional status (Hadley, Tessema, & Muluneh, 2012; Surkan, Kennedy, Hurley, & Black, 2011).
The last underlying cause of undernutrition is unhealthy household environment and lack of health services. An healthy environment can be defined as an environment “with clean air, clean water, safe food, and minimal exposure to harmful chemicals“ (World Health Organization & United Nations Environment Programme, 2010) This notion encompasses all actions allowing for the reduction of environmental contaminants for the families, such as adequate hygiene, proper sanitation and water related equipment, bed nets, etc. Having a healthy environment for the whole family is one key factor helping to prevent the spread of illnesses, particularly diarrhea, while access to water of good quality is essential to prevent child’s undernutrition (Checkley et al., 2004; Esrey, 1996; Sharghi, Kamran, & Faridan, 2011). The presence of functional and quality health services is a prerequisite to treat and cure illnesses, including acute malnutrition. Access and utilization of health centers have to be feasible for both preventive and curative care.
The basic causes of undernutrition take roots at the country level. The state’s social, political, ideological and economic contexts play a critical role on the type of resources available (IASC Global Nutrition Cluster, 2011b). The available natural resources and their monitoring at the global level are key determinants of the country’s wealth. The way the state handles revenues, taxes assets, food and merchandises and the country’s level of corruption also has a direct impact on the country’s economy and the redistribution of resources to the population. For example, social protection policy directly depends on the available state’s budget, on the will of leaders to implement such policies and the country’s capacity to handle them. Developing and maintaining decent national infrastructures such as public schools, roads and health centers are prerequisites to low rates of undernutrition. Indeed, roads of good quality allow for markets supply and efficient redistribution of food within the country; school permits caregiver’s education; and functional health centers are essential to provide adequate care to patients. Besides, politics implemented at country level determine the extent of people’s liberties and the rights of the most vulnerable. In this respect, women’s rights and freedom can directly be linked to maternal and child health, as well as religious and racial discrimination. Instable political contexts, civil violence or internal displacement of population can also be cited as basic causes of undernutrition. From a social point of view, population customs and habits in terms of feeding and care practices play a major role on child nutrition.
Next to the causes described in Figure 2, three transversal aspects can be cited as modulators. First, individual factors, such as genetic predispositions, may modulate the resistance a child has to undernutrition (Ahmed, Haque, Shamsir Ahmed, Petri, & Cravioto, 2009). Secondly, seasonality may differently affects the above mentioned causes, exacerbating vulnerabilities during some key periods of the year and leading to peaks of undernutrition, and more particularly acute malnutrition (Hillbruner & Egan, 2008; Kinyoki et al., 2016). Children’s morbidities are largely impacted by seasonal variations in temperature and rainfalls. During the rainy season, access to good quality water is reduced and the number of water-related diseases increases. In the meantime, some localities are cut from the rest of the countries because of floods, closing the access to health centers or markets. As far as food security is concerned, availability of food is lessened before the harvest period. Time dedicated to care practices also varies with the caregiver’s workload, often depending on the agricultural work (Morwenna Sullivan, 2013). Finally, climate change is also known to intensify hunger and undernutrition, particularly through food insecurity (Food and Agriculture Organization, 2016; Phalkey, Aranda-Jan, Marx, Hofle, & Sauerborn, 2015; World Food Program & Met Office, 2012). Indeed, climate is known to have a crucial importance in food crop productivity. Recurrent floods or droughts negatively affect the soil quality and its hydrological balance, leading to reduced agricultural productivity.
IMPORTANCE OF THE PHENOMENON AT THE INTERNATIONAL LEVEL
Although important progresses have been made since two decades in reducing the burden of childhood undernutrition (Black, Victora, Walker, Bhutta, Christian, de Onis, Ezzati, Grantham-McGregor, Katz, Martorell, Uauy, Bhutta, et al., 2013; Food and Agriculture Organization, International Fund for Agricultural development, & World Food Program, 2015), it remains a public health issue at the international level. Ten years ago, the International Food Policy Research Institute (IFPRI) created the global hunger index (GHI) as a broad measure of hunger in the world and by regions. This index combines four indicators, three focusing on children under 5 years old and one reporting on the global population: undernourishment (or insufficient caloric intake) of the population, child stunting, child wasting and child mortality. The 2015 GHI founds 52 countries with serious or alarming states of hunger. Among them, sub-Saharan countries and South Asian states were the worst in terms of hunger (International Food Policy Research Institute, Concern Worldwide, & Welthungerhilfe, 2015). In absolute numbers, 795 million people were reported as undernourished in 2014-2016 by FAO (Food and Agriculture Organization et al., 2015). This represents one person out of nine in the world. This proportion gets worse in Sub-Saharan Africa, where almost one out of four people was undernourished in 2014-16 (Food and Agriculture Organization et al., 2015).
95 million of under 5 years-old children living in developing countries were categorized as underweight in 2014. This corresponds to one child out of seven living in less developed regions or 16% (World Health Organization, 2016a). The highest prevalence of child underweight were found in Southern Asia (28%) and Western Africa (21%) (Food and Agriculture Organization et al., 2015; World Health Organization, 2016a). Data from 2011 published in the 2013 Lancet Series on Maternal and Child Nutrition estimated that 165 million children aged under 5 years old were stunted, most of them also living in South Asia and Sub-Saharan Africa (Black, Victora, Walker, Bhutta, Christian, de Onis, Ezzati, Grantham-McGregor, Katz, Martorell, Uauy, Bhutta, et al., 2013). In 2015, this number slightly decreased to reach 156 million: nearly one child out of four was stunted (World Health Organization, 2016b).
In 2011, 52 million of under 5 years-old children were suffering from wasting according to the above mentioned Lancet Series (Black, Victora, Walker, Bhutta, Christian, de Onis, Ezzati, Grantham-McGregor, Katz, Martorell, Uauy, Bhutta, et al., 2013). In 2015, this number was reduced to 50 million, representing 7% of all children of this age group worldwide (World Health Organization, 2016b). Figure 3 presents the prevalence of wasting for children aged less than 5 years old, according to the latest available data. Countries of South-Eastern Asia, Sub-Saharan Africa and East Africa are the more affected by under 5 child wasting.
CONSEQUENCES OF UNDERNUTRITION
As shown in Figure 2, two types of consequences of suboptimal energetic or nutrient intake can be distinguished: the short-term complications and the long-term ones, corresponding roughly to diseases and developmental delays.
The short-term consequences of acute malnutrition, and more globally of undernutrition, are morbidity, disability and mortality (Black, Allen, Bhutta, Caulfield, de Onis, Ezzati, Mathers, & Rivera, 2008). Indeed, a child suffering from acute malnutrition, or undernutrition, has a weaker immune system compared to his/her well-nourished peer. This low immunity makes him/her more sensitive to infections, such as diarrhea, measles, malaria and tuberculosis (Katona & Katona-Apte, 2008; U. E. Schaible & S. H. Kaufmann, 2007). Ultimately, this may leads to mortality. A study from 1994 evaluated the risk of dying according to the severity of undernutrition: a severely malnourished child was 8 times more likely to die compared to a non-malnourished child (Pelletier, Frongillo, Schroeder, & Habicht, 1994). At the beginning of the year 2000, Caulfield assessed the risk of dying from a low weight-for-age by cause of death in ten cohort studies. More than 50% of all child deaths were due to low underweight. If a child died because of diarrhea, this percentage increased to nearly 61% (Caulfield, de Onis, Blossner, & Black, 2004). In 2006, the World Bank estimated that undernutrition is associated with almost 60% of all child mortality. Mildly underweight children also faced twice the risk of dying compared to children with adequate nutritional status (The World Bank, 2006). Nowadays, 45% of all deaths among under 5-years old children, or 3.1 million deaths annually, are attributable or caused by nutritional disorders, namely wasting, stunting, vitamin A and zinc deficiencies, fetal growth restriction and inadequate breastfeeding (Black, Victora, Walker, Bhutta, Christian, de Onis, Ezzati, Grantham-McGregor, Katz, Martorell, Uauy, Bhutta, et al., 2013; World Health Organization, 2016a).
Table of contents :
Chapter 1: General introduction
1. Outline of the PhD thesis
2. The problem of acute malnutrition
2.2. Definitions and indicators
2.3. Causes of undernutrition
2.4. Importance of the phenomenon at the international level
2.5. Consequences of undernutrition
2.6. Treatment versus prevention of acute malnutrition
3. Existing interventions to prevent acute malnutrition
4. Cash transfers to prevent acute malnutrition
4.2. Cash transfer and undernutrition
Chapter 2: The unconditional and seasonal aspect of cash transfers for the prevention of acute malnutrition: a critical review of the literature
3. Material and methods
Chapter 3: The MAM’Out study
1. Objective and hypotheses of the research
2. Presentation of the MAM’Out research area
2.1. Burkina Faso
2.2. The Tapoa Province
3. The MAM’Out project: a randomized controlled trial to assess multiannual and seasonal cash transfers for the prevention of acute malnutrition in children under 36 months in Burkina Faso
3.3. Methods / Design
4. Methodological precisions
Chapter 4: Beneficiaries’ Perceptions and Reported Use of Unconditional Cash Transfers Intended to Prevent Acute Malnutrition in Children in Poor Rural Communities in Burkina Faso: Qualitative Results from the MAM’Out Randomized Controlled Trial
Chapter 5: Unconditional seasonal cash transfer increases intake of high nutritional value foods in young Burkinabe children: results of 24-h dietary recall surveys within the MAM’Out randomized controlled trial
Chapter 6: Unconditional cash transfers do not prevent children’s undernutrition in the MAM’Out cluster randomized controlled trial in rural Burkina Faso
Chapter 7: General discussion and conclusion
2. Main findings
2.1. Qualitative results
2.2. Quantitative results
3. Strengths and limitations of the research
4. Public health implication of the research
4.1. Seasonal UCT to improve child diets
4.2. Integrated approach for the prevention of child wasting
5. Further research perspectives