assessing and managing children at primary health-care facilities to prevent overweight and obesity in the context of the double burden of malnutrition. Updates for the Integrated Management of Childhood Illness (IMCI)#
Special thanks are extended to Peggy Henderson and Karimen Leon for their assistance in preparations for the meeting, taking notes during the meetings and their contribution in drafting the guideline, including review of GRADE tables. Thanks are also due to Tania Teninge for assistance with all meeting preparations and Liesl Nicol for her assistance in presenting the systematic reviews at the guide line meetings.

# Financial support
The World Health Organization gratefully acknowledges the financial contribution of the Bill & Melinda Gates Foundation, the Government of Luxembourg and the United States Agency for International Development towards the meeting costs and development of this publication. WHO is grateful to all the individuals and institutions that contributed time and made other in-kind contributions to the guideline development process.
Donors do not fund specific guidelines and do not participate in any decision related to the guide line development process, including the composition of research questions, membership of the guideline groups, conduct and interpretation of systematic reviews, or formulation of recommendations.

# Executive summary
The global epidemic of child and adolescent obesity affects all world regions, includi ng countries where undernutrition remains common. In 2016, 155 million children were affected by stunting and 52 million children were wasted while 41 million children were overweight. Being underweight or stunted are both associated with increased child mortality and morbidity and impaired child development -about 20% of child deaths are still related to malnutrition. However, being overweight or obese also has immediate physical and mental health implications for a child or adolescent, and both are major risk factors for cardiovascular disease, diabetes and premature death in adults. Paradoxically, a history of low birth weight or stunting is a risk factor for children becoming overweight or obese and developing cardiovascular disease or diabetes in later life. The presence of both obesity and underweight in the same populations, communities and even families is commonly referred to as the "double burden of malnutrition" and highlights the life course consequences of nutrition of women in pregnancy and of children in early life with health and well-being in later life. 1

# Rationale for guideline development
The World Health Organization (WHO) Global strategy for infant and young child feeding 2 addresses the needs of all children and advocates for health workers to be empowered in order to provide effective feeding counselling that will promote, protect and support appropriate infant and young child feeding. This is especially relevant given the magnitude of the child obesity epidemic and its relationship with adult noncommunicable diseases; WHO tools therefore need to provide relevant guidance to the full spectrum of health-care providers.
Children with a history of low birth weight, stunting and inappropriate weight gain in the mid-child years (preschool and school) are known to be at greater risk of obesity in later life. 3 Recommendations regarding the prevention or treatment of moderate malnutrition should consider the long-term health consequences of interventions and not focus only on short-term outcomes. 4 WHO guidelines should be reviewed to ensure that recommendations aimed at mitigating the risks of moderate malnutrition do not inadvertently increase the risk of obesity and noncommunicable diseases in later life.
The WHO Integrated Management of Childhood Illness (IMCI) provides clinical algorithms that guide health workers at primary health-care facilities on the assessment and management of infants and children presenting with illnesses, including assessment and classification of nutritional status. Guidance in IMCI 1 on nutrition counselling has generally focused on preventing undernutrition without overweight or obesity. However, the scope of IMCI is under review, with respect to more fully addressing and including health-promotion activities. Given the scale of the global epidemic of child obesity, and the importance of improving the health status of children, it is important that IMCI provides guidance that will contribute to the global effort to end childhood obesity.
This guideline process focused on the prevention of overweight and obesity at primary health-care facilities where IMCI is implemented, including settings where undernutrition is prevalent. However, the recommendations are not comprehensive with respect to the management of children with acute malnutrition or stunting but consider only some specific nutrition-related interventions that may increase or mitigate the risk of adverse health outcomes in these children.
This guideline is intended to help Member States and their partners in their efforts to make evidence-informed decisions on assessing and managing children at primary health-care facilities, to prevent overweight and obesity in the context of the double burden of malnutrition. It will also support their efforts to achieve the Sustainable Development Goals, the global targets set by the Comprehensive implementation plan on maternal, infant and young child nutrition, and the Global strategy for women's, children's and adolescents' health 2016-2030.
The objective of the guideline is to provide guidance on appropriate assessment and management of infants and children at primary health-care facilities, in order to reduce the risk of overweight and obesity among children, including those living in settings where both undernutrition and overweight/obesity are prevalent. Three specific areas and related questions were prioritized: (i) anthropometric assessment and classification of the nutritional status of infants and children presenting to primary health-care facilities; (ii) management of infants and children with acute or chronic malnutrition presenting to primary health-care facilities; and (iii) management of children who are overweight or obese presenting to primary health-care facilities.
The guideline is intended primarily for use in low-and medium-resource settings.
The primary audience for this guideline includes: (i) national policy-makers in health ministries; (ii) development partners providing financial and/or technical support for child health programmes;
(iii) programme managers working in child health and health-worker training; and (iv) health-care providers, researchers and clinicians managing infants and children at various levels of health care; this includes physicians, nurses and auxiliary personnel providing primary health care.

# Guideline development methodology
WHO developed the recommendations using the procedures outlined in the WHO handbook for guideline development. 2 The steps in this process included: (i) identification of priority questions and outcomes; (ii) retrieval of the evidence; (iii) assessment of the quality of the evidence and synthesis of the findings; (iv) formulation of recommendations, including research priorities; and 1 Integrated Management of Childhood Illness. Chart booklet. Geneva: World Health Organization; 2014 (). 2 WHO handbook for guideline development, 2nd ed. Geneva: World Health Organization; 2014 ().
planning for (v) dissemination; (vi) implementation, equity and ethical considerations; and (vii) impact evaluation and updating of the guideline. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) 1 methodology was followed, to prepare evidence profiles related to pre-selected topics, based on up-to-date systematic reviews.
A WHO steering committee and a 17-member guideline development group of experts was convened.
Informed by evidence reviews and other evidence summaries, the WHO steering committee developed an initial set of draft recommendations. Members of the guideline development group declared potential conflicts of interest. One potential conflict was identified; it was agreed that the member could participate in all discussions but that if a vote was required, then the participant would not be eligible to vote. Members of the guideline development group then reviewed and evaluated the quality of the evidence identified through the systematic reviews, using the GRADE method, and revised and finalized the guideline recommendations. The best practice statements and final recommendations agreed by the WHO Guidelines Review Committee are presented.

# Other related WHO recommendations
These recommendations do not reflect all WHO recommendations related to infant and child nutrition but only for those areas prioritized by the guideline development group with respect to infants and children presenting to primary health-care facilities. They highlight practices to mitigate risks in vulnerable populations, e.g. children with wasting or stunting, and interventions to reduce the risk of overweight and obesity in other children. As such, they do not represent comprehensive guidelines on the management of undernutrition but address one aspect of management that may influence the risk of noncommunicable disease and long-term health outcomes.

# Updating this guideline
This guideline will be reviewed and updated in 4-5 years, when WHO will constitute a guideline development group to review the literature and update the recommendations as needed.

# Equity and human right perspectives
The members of the guideline development group considered it important to emphasize the principle of equity and human rights within health care, and the context of infants and children presenting to primary health-care facilities within which recommendations will be implemented. The group formulated the following points:   It is the right of every child to grow normally and be healthy; WHO is committed to this principle.
  WHO recognizes that, in this guideline development process, we are primarily dealing with the child presenting with a clinical problem, and looking at the process of ill-health within a medical model only. Although ill-health is often the consequence of a broader context for health and nutrition, here, in this guideline, we are not focusing our consideration on this broader context; comprehensive solutions are, hence, beyond this guideline's immediate remit.
  Nevertheless, WHO recognizes and notes these broader considerations, and their importance for informing the wider discussions of the guideline development group.
 GUIDELINE: ASSESSING AND MANAGING CHILDREN AT PRIMARY HEALTH-CARE FACILITIES Assessing and managing children attending primary healthcare facilities in order to prevent overweight and obesity

# Best practice statements and Recommendations
Best practice statements 1. All infants and children aged less than 5 years presenting to primary health-care facilities should have both weight and length/height measured, in order to determine weight-for-length/height and to classify nutritional status according to WHO child growth standards. 1 Note: The measurement of mid-upper arm circumference both at health facilities and in the community can be used to identify children with severe or moderate acute malnutrition. 2 However, mid-upper arm circumference cannot be used to determine overweight or obesity, as there are no validated cut-off values as yet. The best practice statement therefore only makes reference to weight and length/height.
- Caregivers and families of infants and children aged less than 5 years presenting to primary health-care facilities should receive general nutrition counselling, including promotion and support for exclusive breastfeeding in the first 6 months and continued breastfeeding until 24 months or beyond.
Note: Against the background of best practice that caregivers of all infants and children aged less than 5 years should receive general nutrition counselling, no recommendation is made regarding providing nutrition counselling that is specific to children with stunting only.
- Routinely providing supplementary foods to moderately wasted infants and children (i.e. with acute undernutrition) presenting to primary health-care facilities is not recommended (strength of recommendation: conditional; low quality evidence).
Note: There may be a role for the provision of supplementary foods in settings where there is a high prevalence of wasting or food insecurity, 3 at community or household level, and as part of the continuum of care for the individual child that includes appropriate treatment of clinical conditions and other modifiable factors, provision of nutritional counselling and subsequent follow-up to assess response.
- The provision of supplementary foods for treating stunting (chronic under nutrition) among infants and children who present to primary health-care facilities is not recommended (strength of recommendation: conditional; low quality evidence).
- At primary health-care facilities, health workers should provide nutrition counselling to caregivers of overweight children aged less than 5 years (strength of recommendation: conditional; very low quality evidence). 4. At primary health-care facilities, health workers should provide counselling on physical activity to caregivers of overweight children aged less than 5 years (strength of recommendation: conditional; very low quality evidence).
- At primary health-care facilities, children aged less than 5 years who are identified as obese should be assessed and an appropriate management plan should be developed. This can be done by a health worker at primary health-care level, if adequately trained, or at a referral clinic or local hospital (strength of recommendation: conditional; moderate quality evidence).
Note: Against the background of best practice that caregivers of all children aged less than 5 years should receive general nutrition counselling, no recommendation is made regarding providing nutrition counselling that is specific to children with stunting only.
The global epidemic of child and adolescent obesity affects all world regions, including countries where undernutrition remains common. In 2016, an estimated 41 million children under the age of 5 years (6.0%), were affected by overweight or obesity (1), defined as the proportion of children with weight-for-length/height z-score 1 values between 2 and 3 standard deviations (SDs) and more than 3 SDs respectively above the median of the World Health Organization (WHO) Child growth standards (2). This represents an increase of about 11 million since 2000 (1). In 2016, of children under 5 years of age who were overweight, 49% lived in Asia and 24% lived in Africa (1). Between 2000 and 2016 the proportion of children who were overweight in Asia increased by 40% (14.2 million to 19.9 million) and in Africa by 48% (6.6 million to 9.8 million) (1).
In the 2012 Global Burden of Disease study (3), it was reported for the first time that more people died of overnutrition than undernutrition. Demographic and nutrition transitions are occurring within low-income countries, even where undernutrition is common. Being overweight or obese has immediate physical and mental health implications for a child or adolescent, and both are major risk factors for cardiovascular disease, diabetes and premature death in adults.
The prevalence of obesity in children reflects changing patterns towards unhealthy diets and physical inactivity. Urbanization, market liberalization, increased incomes, availability of fast foods, educational demands, increased motorized transport, television viewing and gaming have led to a rise in the consumption of foods that are high in fats, sugar and salt and lower levels of physical activity.
At the individual level, the drivers of child and adolescent obesity include factors related to nutrition in pregnancy; infant and child feeding practices; population dietary patterns, including the quality and frequency of family foods; and lifestyle issues such as decreased physical activity, increased sedentary behaviour and school and family health-promotion programmes. While there have been major public health interventions to promote improved diet and patterns of physical activity in adults, the contribution of antenatal and young-child interventions to reducing the risk of obesity in later life have not been significantly reviewed.
Paradoxically, children who were born with low birth weight, have suffered from undernutrition and/or have a low length/height-for-age (stunting) are at greater risk of developing overweight and obesity when faced by energy-dense diets and a sedentary lifestyle later in life (4). This highlights the life course consequences of nutrition of women in pregnancy and of children in early life with health and well-being in later life.
In May 2012, the 65th World Health Assembly endorsed the Comprehensive implementation plan on maternal, infant and young child nutrition, including six global nutrition targets (5), and urged Member States to put it into practice by including proven nutrition interventions relevant to their country. The political declaration of the Second Conference on Nutrition, held in Rome, Italy, in November 2014 (6), addressed the multiple challenges of malnutrition in all its forms in relation to inclusive and sustainable development and health. The normative mandate of WHO aims to strengthen the evidence base of effective and safe nutrition actions to counteract the public health effects of the dual burden of malnutrition, and to describe good practices for successful implementation.
In 2014, the WHO Commission on Ending Childhood Obesity noted the double burden of malnutrition, i.e. undernutrition and obesity coexisting, in many countries (4,7,8). The commission commented that attempts to deal with undernutrition and stunting during childhood may have led to the unintended consequence of increased obesity risk for these children (4).
Interventions to treat or prevent one form of malnutrition need to be understood and implemented in the context of other recommendations related to protecting and promoting optimal infant and child feeding in the general population. The WHO Global strategy for infant and young child feeding (9) describes the essential interventions to protect, promote and support breastfeeding and complementary feeding. In many settings where infant and child undernutrition is common, the use of commercial breast-milk substitutes and other replacement feeds is associated with significantly increased morbidity and mortality. In these settings and elsewhere, the evidence for the long-term benefits of breastfeeding for both maternal and child health outcomes, including child development and prevention of noncommunicable diseases, highlights the relevance of protecting, promoting and supporting breastfeeding in high-and low-income settings alike (10).

# The Integrated Management of Childhood Illness
The Integrated Management of Childhood Illness (IMCI) is an integrated approach to child health that focuses on the well-being of the whole child (11). IMCI aims to reduce death, illness and disability, and to promote improved growth and develop ment among infants and children aged less than 5 years. IMCI includes both preventive and therapeutic elements that are implemented by families and communities as well as by health workers in facilities.
In health facilities, the IMCI strategy focuses on infants and children presenting with an illness and promotes the accurate identification of childhood illnesses in out patient settings, ensures appropriate combined treatment of all major illnesses, strengthens the counselling of caregivers, and speeds up the referral of severely ill children.
IMCI consists of numerous clinical algorithms and training materials that assist nurses and other primary health-care workers to manage sick infants and children presenting to health facilities, and were developed largely to suit low-resource settings. IMCI includes growth charts for infants aged 0-2 months and 2-59 months. Nutrition assessment is integral to the evaluation of sick infants and children and is also central to the care of the well child and promoting their health and development. IMCI therefore includes algorithms for use by health workers based at primary health-care facilities that reflect WHO recommendations on anthropometric assessment and infant and child feeding. These are summarized in Fig. 1 and Fig. 2.
However, the scope of IMCI algorithms for assessment and treatment is under review, in order to identify additional opportunities for promoting good health.
The global epidemic of childhood obesity is likely to fuel an increasing burden of cardiovascular disease and type 2 diabetes mellitus in adults. While interventions at primary health-care facilities will not in themselves reverse this trend, it is important that health workers at all levels contribute to the overall effort. Health workers therefore need guidance on how to appropriately respond as part of their daily activities.
- Interventions to treat or prevent moderate malnutrition, i.e. wasting and stunting, may increase the risk of overweight or obesity in children While moderate wasting and stunting are associated with increased morbidity and mortality in some children, there is emerging evidence that inappropriate weight gain in childhood, especially the mid-child years, is associated with increased obesity in adolescence and adulthood. It is therefore important that recommendations regarding the prevention or treatment of moderate acute malnutrition should consider the long-term health consequences of interventions and not focus only on short-term outcomes. WHO guidelines should be reviewed to ensure that recommendations aimed at mitigating the risks of moderate acute malnutrition do not inadvertently increase the risk of obesity and noncommunicable diseases in later life.
- IMCI does not provide guidance on the assessment and management of children who are already overweight or obese.
IMCI is extensively used globally as a resource for health-care workers at primary health-care level.
It is dependent on evidence-informed WHO recommendations. Despite the magnitude of the global epidemic of childhood obesity, IMCI does not make reference to assessment or management of overweight or obesity in infants and children. While a single guideline process will not be able to provide comprehensive guidelines for the prevention and treatment of overweight and obesity in infants and children, it is important to start a process whereby actions can be taken and interventions offered by primary health-care workers. It is noted that these should be complemented by actions and interventions offered at referral centres. However, these are beyond the scope of this guideline process.
While this guideline has been developed to support health workers at primary health-care facilities where undernutrition is prevalent, it does not comprehensively address the management of infants and children with acute malnutrition or stunting. The recommendations consider only some specific nutrition-related interventions that may increase or mitigate the risk of later adverse health outcomes in these children.

# Scope and purpose of the guideline
This guideline aims to provide guidance on the appropriate assessment and management of infants and children at primary health-care facilities, in order to reduce the risk of overweight and obesity among children, including those living in settings where both undernutrition and overweight/ obesity are prevalent. Recommendations from the guideline will be used to update WHO-related tools and training materials, in particular IMCI.
The guideline addresses the following three areas:
  anthropometric assessment and classification of the nutritional status of infants and children presenting to primary health-care facilities;
  management of infants and children with acute or chronic malnutrition presenting to primary health-care facilities;
  management of children who are overweight or obese presenting to primary health-care facilities.
The guideline is intended primarily for use in low-and medium-resource settings.
The primary audience for this guideline is (i) national policy-makers in health ministries; (ii) development partners providing financial and/or technical support for child health programmes;
(iii) programme managers working in child health and health-worker training; and (iv) health-care providers, researchers and clinicians managing infants and children at various levels of health care. This includes physicians, nurses and auxiliary personnel providing primary health care.
It will also inform revisions to current WHO training and reference materials, including: Integrated Management of Childhood Illness (12); Infant and young child feeding counselling: an integrated course (13); Essential newborn care course (14); and Caring for newborns and children in the community: a training course for community health workers, which includes courses on Caring for the newborn at home, Caring for the sick child and Caring for the child's healthy growth and development (15)(16)(17).
This guideline should not be considered as comprehensive guidance for the management of either undernutrition or overweight/obesity. Additional guidance will be developed by WHO in the future to complement and expand this guideline.
Successful implementation will require appropriate training and capacity development of healthcare workers, to enable them to acquire the necessary skills. Systematic monitoring and evaluation of programmes will also be needed to identify and document challenges to implementation.
At a higher level, the guideline will contribute to the efforts of Member States and their partners to make informed decisions on the appropriate nutrition actions to achieve the Sustainable Development Goals (SDGs), the global targets set in the Comprehensive implementation plan on maternal, infant and young child nutrition (5) and the Global strategy for women's, children's and adolescents' health (2016-2030) (18).

# Population of interest
This guideline focuses on infants and children aged less than 5 years and their caregivers presenting to primary health-care facilities in settings where the IMCI approach is in place.
Complementary guideline processes will address guidance on prevention and treatment of overweight and obesity at referral centres and in older populations of children and adolescents.

# Programmatic questions for review
The following questions were identified as priorities where existing recommendations, especially those incorporated in IMCI should be reviewed and updated, or new guidance developed. Prior to the guideline meeting, the WHO steering committee decided not to include question 4 in the review process, as the evidence and programmatic issues related to the question were deemed too complex to address within the timeline of the guideline meeting and it was felt that they should be considered as a stand-alone exercise.
For each question, outcomes that were deemed to be either "Critical" or "Important" were evaluated.
In preparation for the meeting, and to inform the guideline development group:   each priority guideline question was described in terms of the population, intervention, comparison and outcome (PICO; Annex 5) and systematic reviews were commissioned to examine the available evidence;
  a meta-analysis of demographic and health survey data was commissioned to provide relevant contextual data (Annex 1);   a survey of IMCI chart booklets and clinical algorithms used in different countries was conducted to inform the guideline development group regarding current uptake and adaptations of IMCI at national level -information from the survey is included in relevant sections of the decisionmaking information presented for each recommendation.
The guideline process is more fully described in the Methods section.

# Equity and human right perspectives
The members of the guideline development group considered it important to emphasize the principle of equity and human rights within health care, and the context of infants and children presenting to primary health-care facilities within which recommendations will be implemented.
The group formulated the following points: Children with severe wasting or severe acute malnutrition have significantly increased mortality risk, though appropriate treatment significantly reduces mortality (19,20). Children with moderate wasting and/or stunting also have increased mortality risk, although less than for severe wasting or wasting and stunting combined (21).
  It
In an individual patient meta-analysis of 53 607 participants and 1306 deaths, the risk of allcause mortality was elevated among children with one, two or three anthropometric deficits. In comparison with children with no deficits, the mortality hazard ratios were 3.4 (95% confidence interval : 2.6 to 4.3) among children who were stunted and underweight but not wasted; 4.7 (95% CI: 3.1 to 7.1) in those who were wasted and underweight but not stunted; and 12.3 (95% CI: 7.7 to 19.6) in those who were stunted, wasted and underweight (21).
In children, moderate acute malnutrition (moderate wasting) may be transient and experienced by children in the course of an acute illness. Moderate wasting may also be due to chronic illnesses such as tuberculosis (TB) or HIV, or can also be the result of food insecurity and inadequate dietary intake. Management of moderate wasting should include a range of essential nutrition actions such as breastfeeding promotion and support, education and nutrition counselling for families, and other activities that identify and prevent the underlying causes of malnutrition, including nutrition insecurity. Interventions to improve food insecurity include the provision of conditional or nonconditional cash transfers and support to agriculture, such as crop diversification (22). Children with moderate wasting need nutrient-rich foods to meet their extra needs for full recovery (22). In the context of food insecurity, food supplements may have a role and food programmes have been established in many humanitarian crises or other settings of chronic food insufficiency.
Historically, anthropometric assessments and nutrition classifications in IMCI focused on identifying infants and children with undernutrition because of the associated health consequences. The classification of undernutrition included in IMCI focused on assessing weight-for-age because it is simpler to measure than the length or height of children. Children whose weight-for-age was less than the third percentile were classified as "very low weight". However, this classification did not necessarily reflect the relevant risks of morbidity and mortality. For example, one child may have a very low weight-for-age because he or she is stunted or has a history of low birth weight. In contrast, another child who is taller may have the same weight-for-age and is wasted because he or she has suffered a recent acute or serious illness. Similar considerations are relevant for children and classifications for overweight and obesity.
Therefore, with respect to both wasting and overweight and obesity, it is important to relate a child's weight-for-age to their length/height, in order to correctly interpret their nutritional status.
In the context of the double burden of malnutrition, it is therefore important that a public health approach, such as IMCI, correctly identifies children who are at risk of clinically important undernutrition (severe or moderate wasting, or severe acute malnutrition) and also children who are at risk of overweight and obesity.

# Summary of the evidence
Three reviews of relevant information were completed to contextualize the environment in which recommendations may be implemented and to assist the guideline development group to make informed decisions. Details of the review teams and references are presented in Annex 1, Annex 2a and Annex 2b.
  A meta-analysis of epidemiological anthropometric data of infants and children from different regions. This shows regional differences in rates of undernutrition and stunting in infants and children (23).
  A systematic review of the relationship between anthropometric measures in childhood and short-and long-term health outcomes (24).
Note: Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tables (25) were not developed but comprehensive tables summarizing the evidence for associations between anthropometric measures in early childhood and anthropometric and health outcomes in adulthood are included in the report.
  A survey of IMCI chart booklets and clinical algorithms used in different countries, reporting current uptake and adaptations of IMCI at national level (26).
The first, an epidemiological analysis of surveys conducted in 63 low-and middle-income countries (1993-2012) (23) reported that between 0.4% and 18.6% of children (aged 6-59 months) would be classified as "very low weight", i.e. weight-for-age more than 3 SD below the WHO child growth standards (2) (Bangladesh 14.1%, Chad 15.7%, India 18.6%, Niger 16.3%, Timor Leste 16%). The vast majority of these children are also stunted (low length/height-for-age). The proportion who were "very low weight" and also wasted varied by region. In Central and South American and Caribbean countries, 0.4-2% of stunted children were concurrently wasted, whereas in Africa and South Asia 0.5-11% were also wasted (see distributions by regions in Annex 1 (23)). The analyses highlight the regional differences in rates of undernutrition and stunting in infants and children, and the importance of correct classification of nutritional status for individual-based recommendations.
The second, a systematic review (24), analysed data from 52 studies (36 cohorts or longitudinal studies) that reported data on the association of anthropometric measures during infancy and childhood and the risk of developing obesity in later life (childhood, adolescence or adulthood).
A meta-analysis using a random-effects model showed a significant inverse association of correlation coefficients. The pooled analysis of BMI showed a decreasing trend when tracked from early childhood (3-6 years) to mid childhood (9-11 years; r = 0.79, 95% CI: 0.71 to 0.87), adolescence (12-18 years; r = 0.66, 95% CI: 0.53 to 0.78), adulthood (19-40 years; r = 0.39, 95% CI: 0.29 to 0.50) and late adulthood (>40 years; r = 0.26, 95% CI: 0.18 to 0.34); mid childhood (9-11 years to adolescence (12-18 years; r = 0.81, 95% CI: 0.73 to 0.88), adulthood (19-40 years; r = 0.58, 95% CI: 0.50 to 0.66). BMI tracking showed similar trends in low-and middle-income countries and high-income countries.
Thirteen studies showed that high BMI in childhood or adolescence was associated with a high risk of overweight or obesity in later life. The majority of the studies predicted a high risk of becoming overweight or obese with higher weight status during infancy and childhood.
Rapid weight gain in infancy and childhood was also strongly associated with the risk of overweight or obesity in adolescence or adulthood. Evidence from cohort studies showed that children who gained excess weight in "mid-child years" (age 4 years in four of the birth cohorts and age 8 years in one birth cohort) are at significant risk of obesity, diabetes and cardiovascular disease in adult life (27).
Eleven articles (including two consortia) from 13 cohorts discussed the associations of various anthropometric measures during infancy or childhood and cardiovascular morbidity and mortality in later life.
Four cohort studies showed that higher BMI during childhood was associated with cardiovascular disease morbidity and mortality during adult life. One cohort study (Helsinki Birth Cohort) showed that lower BMI during early childhood was associated with higher risk of cardiovascular disease during adult life. However, this finding was not consistent across all cohort studies. Two cohort studies, one each from Great Britain and the United States of America, did not find any association between childhood BMI and adult cardiovascular disease. The pooled results from three British cohorts found a significant relationship between being persistently overweight throughout childhood until adult life and coronary artery disease in later life. Pooled results from three historical British birth cohorts attributed minimal risk for ischaemic heart disease when childhood BMI was high. One cohort study (Helsinki) showed that lower weight and/or shorter length at 1 year of age increased the morbidity and mortality due to cardiovascular disease in adult life. Low weight-forage at 1 year may have been due to low birth weight or being small for gestational age.
Findings regarding associations between childhood weight and height and systolic and diastolic blood pressure were not consistent. Among 29 283 subjects in 12 cohorts, 9 studies reported positive associations between BMI in childhood (2-12 years) and adolescence (12-18 years) and raised adult systolic and diastolic blood pressure measured between 19 and 50 years. One study, however, reported no association after adjusting for adult BMI.
In summary, there were strong correlations between high weight-for-length/height/BMI (and other markers of adiposity such as skinfold thickness) in early to mid-childhood and the prevalence of obesity, cardiovascular disease and diabetes in adolescents and adults (24).
The third review was a brief survey carried out by WHO in 2015 for the purpose of this guideline process (26), which found that anthropometric assessment of infants and children in the national IMCI chart booklet had been updated in 19 countries. In these versions, the combination of measurement most frequently included to assess nutritional status was weight-for-age + weightfor-length/height + mid-upper arm circumference, whereas in previous versions only assessments of weight-for-age were included. Clinical signs were used more frequently than anthropometric measurements to define acute malnutrition; "visible severe wasting" is still being used as a criterion in 39 countries despite no longer being recommended by WHO since 2013.
A separate growth-monitoring programme is carried out in 39 countries, mostly together with routine immunizations. Growth monitoring is most commonly performed in children below the age of 5 years. The anthropometric measurement used most frequently for growth monitoring was weight-for-age, then weight-for-length/height and length/height-for-age. Data on coverage of growth monitoring among children (up to 12 months of age) were available in 23 countries; high coverage of growth monitoring (80-100%) was reported in 12 countries (26).

# Best practice statement
With respect to anthropometric assessment of infants and children presenting to primary healthcare facilities, a statement on best practice was agreed.
Best practice statement: All infants and children aged less than 5 years presenting to primary health-care facilities should have both weight and length/height measured, in order to determine weight-for-length/height and to classify nutritional status according to WHO child growth standards (2).
Note: The measurement of mid-upper arm circumference both at health facilities and in the community can be used to identify children with severe or moderate acute malnutrition (19). However, mid-upper arm circumference cannot be used to determine overweight or obesity, as there are no validated cut-off values as yet. The best practice statement therefore only makes reference to weight and length/height.
The guideline development group considered that the statement did not constitute a recommendation that could be supported by comparative clinical studies. Instead, they considered it is self-evident that a child with acute undernutrition or who is overweight or obese must be identified, in order for appropriate interventions to be provided. No evidence was presented regarding the ability of health workers to effectively measure and interpret length/height and weight measurements to appropriately classify children. While growth monitoring is a common part of child health services, it is often challenging to do accurately (28,29).
The group agreed, however, that they should make a formal statement that assessment of anthropometric status is important and provides the critical background against which several other important care and treatment decisions would be made. The group therefore decided that it was appropriate to formulate and present a best practice statement.
The group noted that using weight alone to inform clinical decisions leads to significant misclassification of nutritional status. One way to minimize this misclassification would be to standardize measurement of length/height in the context of IMCI. With this information, health workers would be able to provide appropriate nutrition counselling, e.g. information about food quality, and avoid inappropriate guidance such as advising parents whose children are underweight but of low length/ height (therefore normal weight-for-length/height) to eat more.
An evidence base on health outcomes associated with reduced weight-for-length/height is available but there is no evidence on the impact of performing the assessment in routine conditions. Some members of the guideline development group felt that measuring length/height is not useful unless it is done properly. Also, it may not always be possible to measure length/height, and it could be an extra task carried out at the expense of some other health-worker activity.
Countries in the WHO Region of the Americas measure length/height routinely. Implementation was done with sensitization and advocacy for its importance, which has helped to put it into practice.
The arguments in favour of a recommendation were that if there were a recommendation to measure length/height routinely, then the strategy for implementation, including training, would be established.
Suggesting a "best practice" was considered to give flexibility to countries and reflect that measuring length/height may not always be possible.

# Implementation considerations
Considerable initial training and feedback will be required to establish good measurement processes at health-care facilities.

# Research priorities
A better understanding of the use and feasibility of biomarkers present in childhood to predict obesity and the risk of cardiovascular disease or diabetes mellitus in adolescence and adulthood.

# Care of infants and children with acute or chronic malnutrition presenting to primary health-care facilities

# Programmatic questions
a. Should primary health-care workers counsel caregivers of, or otherwise intervene among, infants and children who are moderately wasted?
b. Should primary health-care workers counsel caregivers of, or otherwise intervene among, infants and children who are stunted?
Children with a history of low birth weight, or acute or chronic undernutrition, are at increased risk of morbidity and mortality during childhood (21) and are also at increased risk of overweight, obesity and cardiovascular disease in later life (30). They are also at greater risk of metabolic syndrome, including type 2 diabetes mellitus (31). The basis for the additional risk is not fully understood; however, it is thought that infants born with low birth weight have adapted to an in-utero environment in which fetal nutrition is suboptimal, such that their energy needs in infancy and childhood are reduced (32,33). However, later, if presented with high-energy diets containing sugar or fat, these children may gain excess adipose tissue without gaining additional lean tissue or achieving improved linear growth (34). This concept is sometimes referred to as the developmental origins of health and development. Infants who experience moderate degrees of wasting and become stunted for whatever reason, may similarly have altered energy requirements in early childhood.
For these reasons, there is a potential, inadvertent risk of promoting overweight and obesity, or inappropriate gains in adipose tissue, if high-energy food supplements are given in response to stunting in childhood populations, or as part of efforts to treat or prevent moderate wasting.
The management of children presenting with moderate wasting is further complicated by the range of conditions that may decrease normal dietary intake or increase catabolic, physiological processes that can cause wasting. Acute illnesses may cause a child to lose their appetite and experience transient losses in weight. As such, children who experience moderate wasting may fully recover both nutritionally and functionally, as long as they receive adequate, high-quality nutrient-dense foods (22). If illnesses are severe or recurrent, then acute wasting may follow. Chronic infections such as TB or HIV infection may increase metabolic demands and also result in acute wasting. If appropriate anti-tuberculous or antiretroviral treatment is not given, then these children may experience severe wasting and are at high risk of death. Moderate wasting may also be the result of food insecurity and prolonged periods of inadequate dietary intake. In crisis settings, where there is a high prevalence of wasting or food insecurity (7), at community or household level, family food programmes may be implemented to avert increased infant and child mortality.
IMCI has historically emphasized dietary counselling as part of routine care of all infants and children presenting to primary health-care facilities with an illness. When the nutritional status of a child is normal, a mother is encouraged and reminded of good infant and child feeding practices, including exclusive and continued breastfeeding, appropriate complementary foods and family foods (see Figs. 1 and 2). If a child is found to have severe acute malnutrition, he or she is assessed for complications and either treated with therapeutic foods as an outpatient or admitted for additional treatment if found to have signs of sepsis. There has been no explicit guidance for health workers when they identify a child with moderate wasting and stunting.

# Summary of the evidence
  A systematic review was commissioned for this guideline and contributed to the GRADE tables and evidence for this question (see Annex 2c) (35).
Note: The summary of evidence presented next reflects the terminology used by authors of the original scientific publications.

# Counselling of caregivers of children with moderate wasting
One randomized controlled trial (RCT) reported on outcomes related to the effect of counselling and education to caregivers versus no education (36). The study methods were poorly described and hence the risk of bias is unclear. The authors investigated the effect of a home-based nutritioneducation programme versus no education on the growth and psychological performance of moderately underweight (72% of expected weight-for-age without oedema or 79% of expected weight-for-age with oedema) children aged 7-36 months. The nutrition-education programme was provided to the mothers for a few months. The authors did not report on the short-term outcomes of the investigation, but instead on the growth and psychological functioning of the children 3 years later. The counselling did not address breastfeeding practices in younger children. There were no statistically significant differences in physical growth or psychological functioning of the children whose mothers had or had not received the nutrition-education programme.
 GUIDELINE: ASSESSING AND MANAGING CHILDREN AT PRIMARY HEALTH-CARE FACILITIES

# Counselling of caregivers of children who are stunted but not wasted
No studies were identified that reported on the effectiveness of providing nutrition counselling to caregivers of children with stunting but no wasting.