Objectives. What is undernutrition? What is undernutrition? What does undernutrition look like?

Transcription

1 Objectives Basics Jean-Pierre Habicht, MD, PhD Professor Division of Nutritional Sciences Cornell University Types and causes Determinants Consequences Global occurrence and progress Way forward What is undernutrition? What is undernutrition? Failure to eat enough food and absorb the essential nutrients to Perform well Be healthy Survive Energy Protein Essential fatty acids Vitamin A Vitamin C Vitamin B12 Folate Calcium Iron Iodine Zinc Etc. Deficiencies in any of these nutrients What does undernutrition look like? From: WHO From: WHO Marasmus Kwashiorkor

2 Inapparent undernutrition Inapparent undernutrition 125 cm 7 years old 103 cm 7 years old 100 cm 4 years old Causes of undernutrition Immediate causes Poor Diet Disease Underlying causes Basic causes From: UNICEF Diet From: UNICEF Breastfeeding Exclusive 0-5 months Continued 6-23 months Complementary feeding 6-23 months

3 Disease How does it happen? The infection undernutrition cycle Inadequate diet Loss of appetite Malabsorption Increased nutritional requirements Weight loss Growth faltering Lowered immunity From: UNICEF Increased incidence, severity and duration of disease and infection Sick people are more likely to get undernourished. Undernourished people are more likely to get sick. Severity is worse and duration of illness is longer in undernourished individuals. Illness causes more stunting in children consuming inadequate diet Growth (m mm) Supplemented Unsupplemented % of time ill with diarrhea From: Rivera J, et al. Archivos Latinoamericanos De Nutricion 1989; 39: 292 Illness causes more stunting in children consuming inadequate diet Illness causes more stunting in children consuming inadequate diet Growth (m mm) mm Supplemented Unsupplemented Growth (m mm) mm Supplemented Unsupplemented % of time ill with diarrhea % of time ill with diarrhea From: Rivera J, et al. Archivos Latinoamericanos De Nutricion 1989; 39: 292 From: Rivera J, et al. Archivos Latinoamericanos De Nutricion 1989; 39: 292

4 When does illness lead to undernutrition? Bottom line. Illness does not lead to undernutrition among those with adequate diets. But. When does illness lead to undernutrition? Illness leads to more and more severe undernutrition if the diet is inadequate. When does illness lead to undernutrition? The conceptual framework One can control the deterioration of nutrition by illness by assuring adequate nutrition. Good nutrition prevents cumulative pernicious effects of illness. From: UNICEF. State of the World s Children New York: 1998 The conceptual framework What are the underlying causes of undernutrition? has many inter-related causes which need to be identified in order to be effectively addressed. The conceptual framework, first developed by UNICEF in 1990, has been very important in helping people frame their ideas and discussions.

5 The conceptual framework The conceptual framework leads to Impaired physical and mental development Death in short term How does undernutrition kill? Of the deaths in children 2 days to 5 years old: kills about 50% Infectious diseases kill about 80% The 80% includes double counting of children who die because they have both undernutrition and infectious disease. How does undernutrition kill? Of the deaths in children 2 days to 5 years old: Causes of child deaths from 2 days to 5 years old Malaria 15% Pneumonia 30% Other 14% Infection alone 30% Infection AND undernutrition 50% 80% 53% Measles 6% Diarrhea 27% HIV/AIDS 5% Injuries 5% From: Caulfield LE, et al. Am J Clin Nutr 2004; 80:193.

6 Causes of child deaths from 2 days to 5 years old Malaria 15% Pneumonia 30% Causes of child deaths from 2 days to 5 years old Malaria 15% Pneumonia 30% Other 14% Other 14% 53% Measles 4% Measles 6% Diarrhea 27% HIV/AIDS 5% Diarrhea 27% HIV/AIDS 5% Injuries 5% From: Caulfield LE, et al. Am J Clin Nutr 2004; 80:193. Injuries 5% From: Caulfield LE, et al. Am J Clin Nutr 2004; 80:193. and infection kill together directly Overlap of circles is proportion of deaths due to synergism between undernutrition and infection. and infection kill together directly Overlap of circles is proportion of deaths due to synergism between undernutrition and infection. Number of undernourished children who died Synergism + Number of sick children who died Number of undernourished children who died Overlap + Number of sick children who died Overlap = Number of children who died who had both undernutrition AND infection and infection kill together directly Overlap of circles is proportion of deaths due to synergism between undernutrition and infection. and infection kill together directly Overlap of circles is proportion of deaths due to synergism between undernutrition and infection. Undernourished children Become sick Die of infection because of undernutrition Undernourished children Become sick Die of infection because of undernutrition Sick children Become undernourished Die of undernutrition because of infection

7 Causes of child deaths from 2 days to 5 years old Malaria + Malaria 7% 7% Pneumonia 15% kills Other 7% Other + 7% Diarrhea 13% Diarrhea + 14% Pneumonia + 15% Measles 3% Measles + 3% HIV/AIDS 2.5% HIV/AIDS + 2.5% Injuries 5% causes more than half of all deaths among children 2 days to five years old. It kills directly not through causing more disease. From: Caulfield LE, et al. Am J Clin Nutr 2004; 80:193. Every level of undernutrition kills For an individual child, severe acute malnutrition (SAM) is more deadly than less severe undernutrition. Less severe undernutrition, however, is much more common. Therefore, globally, more deaths total occur among the less severely undernourished who appear healthy. Less children will die if the number of ill children who are undernourished decreases. if the number of children who become ill decreases. Effect of disease prevention is larger if undernutrition is prevalent. Uncertainty about proportion of children killed by undernutrition Previous to 1993, official estimates said less than 1% of child deaths were due to undernutrition. From , official estimates said slightly more than 50% of all child deaths were due to the synergism of undernutrition with infectious diseases. Uncertainty about proportion of children killed by undernutrition In 2008, new estimates were published indicating that 35% of child deaths were due to undernutrition. This 35% estimate includes neonatal (1 st day of life) deaths (37% of all child deaths) in the denominator. From: Black RE, et al. Lancet 2008;371:243

8 Causes of child deaths from 1 day to 5 years old 1 st day deaths 37% 35% Pneumonia 19% Measles 4% HIV/AIDS 3% Injuries 3% Causes of child deaths from 1 day to 5 years old 1 st day deaths 37% 35% Pneumonia 19% Other 9% Measles 4% HIV/AIDS 3% Injuries 3% Malaria 8% 53% Pneumonia 30% Malaria 8% Other 9% From: Bryce J, et al. Lancet 2005; 365:1147. Black RE, et al. Lancet 2008;371:243. Diarrhea 17% Malaria 8% Other 9% Diarrhea 17% Deaths from undernutrition Total deaths from 1 st day to 5 years old Diarrhea 17% Injuries 5% Measles 6% HIV/AIDS 5% Deaths from undernutrition Total deaths from 2 nd day to 5 years old Are 1 st day deaths relevant? Our interest is in preventing deaths by improving nutrition with infant and young child and nutrition interventions. Programs targeting children from birth to 5 years of age do not prevent the first day deaths. Such programs can prevent half of all deaths of those to whom the program is targeted. This does not include those who die at or right after birth. Proportion of preventable deaths in children 2 days to 5 years old Other 14% Diarrhea 27% Malaria 15% 53% Injuries 5% Pneumonia 30% From: Caulfield LE, et al. Am J Clin Nutr 2004; 80:193. Measles 6% HIV/AIDS 5% Points for clarification Points for clarification Perceived discrepancy in proportion of children killed by undernutrition. (53% vs. 35%) Serious discrepancies block policy. Discrepancy depends on whether 1 st day deaths are presented and part of the denominator. has a direct effect on death. Direct effect on death is important for major policy decisions. Both disease and undernutrition have equally direct effects due to synergism neither is more underlying than the other.

9 Take-away message is the major single cause of death in the world whether or not deaths in the first day are counted. More deaths can be prevented by preventing undernutrition than by preventing any other cause of death. Lifelong impact of undernutrition has a lifelong negative impact on physical and mental development and leads to: Reduced school performance Reduced productivity and income-earning capacity in adult life Low birth weight in offspring What is malnutrition? Assessment of nutrition status Types Acute (SAM*, MAM) Chronic (stunting) Micronutrient* Measures Underweight (weight-for-age) Stunting (length or height-for-age) Wasting (weight-for-height) Overnutrition Types Overweight Obese Something Measures Body mass index (BMI) Stunting (length or height-for-age) Wasting (weight-for-height) Anthropometry Child size is a reflection of health and nutritional status when it is limited by undernutrition Not interested in size per se in contrast to those who raise livestock Biochemical i indices Levels of nutrient in blood Clinical assessment Physical examination to detect symptoms of undernutrition Dietary assessment Useful for counseling but not assessing nutritional status Anemia Vitamin A deficiency From: WHO. Worldwide prevalence of anemia Geneva: 2008 From: WHO. Global prevalence of vitamin A deficiency in populations at risk Geneva: 2009

10 Iodine deficiency Z-scores (weight or height of subject) median reference value standard deviation of reference population From: WHO. Iodine status worldwide. Geneva: 2004 Reference population Undernourished population Major downward shift of entire weight-for-height distribution during severe famine in southern Sudan, March, WHO. Physical Status: The Use and Interpretation of Anthropometry. Geneva: 1995 Undernourished population Extent of undernutrition = distribution of undersized children The WHO Global Database on Child Growth Moderate undernutrition: Z-score < -2 SD Severe undernutrition: Z-score < -3 SD Major downward shift of entire weight-for-height distribution during severe famine in southern Sudan, March, WHO. Physical Status: The Use and Interpretation of Anthropometry. Geneva: 1995

11 195 million children under 5 suffer from stunting Number of children under 5 years old who are moderately or severely stunted (2008) Equity gaps in stunting prevalence Sub-Saharan Africa South Asia Middle East, North Africa Latin America, Caribbean Europe, Central Asia Prevalence gap between the poorest (red) and richest (blue) quintiles (%) UNICEF. Tracking Progress on Maternal and Child Nutrition; New York: 2009 From: Gwatkin DR, et al. Socio-economic differences in health, nutrition, and population. Washington, DC: The World Bank, 2007 n of children <5 o are stunted Proportion years wh Prevalence of stunting has declined.. Around Around Under-5 mortality declined between 1990 and 2008 Sub-Saharan Africa South Asia Middle East and North Africa East Asia and the Pacific Latin America and Caribbean CEE/CIS* Industrialized countries Developing countries World UNICEF. Tracking Progress on Child and Maternal Nutrition; New York: Under-five mortality rate (per 100,000 live births) *Central and Eastern Europe/Commonwealth of Independent States From: UNICEF. Progress for Children 2010; New York: 2010 Unequal progress in under-5 mortality rate (U5MR) 2/3 of the progress made in reducing mortality has been made at the expense of equality. Way forward: setting priorities From: UNICEF. Progress for Children 2010; New York: 2010

12 Z-scores (WH HO) The window of opportunity for optimal IYCF practices to prevent undernutrition Age (months) Height for age (HAZ) Cost-effective proven interventions are known Maternal and child undernutrition is the underlying cause of 1.5 million deaths and 25% of the disease burden in children younger than five years. Black RE et al. The Lancet Series Child Survival Neonatal Survival Maternal Survival Sexual and Reproductive Health Child Development Maternal and Child From: Victora CG, et al. Pediatrics 2010;125:e473. Take-away message Most of undernutrition happens during the window of opportunity in a child s life. Infant and Young Child Feeding (IYCF) is of greatest importance. Need to focus on scaling up practical, cost-effective, community-based interventions that are best designed to reach the women and children in greatest need. This training course was jointly developed by the Infant and Young Child Feeding Unit, Nutrition Section, UNICEF Headquarters, and Cornell NutritionWorks, Division of Nutritional Sciences, Cornell University. We acknowledge the cooperation of the United Nations University. Copyright 2011