John W.L. Puntis
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WHO standard growth charts [2] (see Chapter 4.1), and basic laboratory indices (see Chapter 1.2.4) if possible. In addition, skinfold thickness and mid-upper-arm circumference measure- ments provide a simple method for estimating body composition [3] .
Nutritional Intake
Questions regarding mealtimes, food intake and difficulties with eating should be part of routine history taking and give a rapid qualitative impres- sion of nutritional intake (see Chapter 1.2.2). For a more quantitative assessment, a detailed dietary history must be taken which involves recording a food diary or (less commonly) a weighed food in- take. This would usually be undertaken in con- junction with an expert paediatric dietician. Use of compositional food tables or a computer software programme allows these data to be analysed so that a more accurate assessment of intake of energy and specific nutrients can be made. When considering whether such intakes are sufficient, dietary refer- ence values provide estimates of the range of en- ergy and nutrient requirements in groups of indi- viduals [4] . Many countries have their own values and international values have been published by the Food and Agriculture Organization/WHO/
United Nations University. Dietary reference val- ues are based on the assumption that individual requirements for a nutrient within a population group are normally distributed and that 95% of the population will have requirements within 2 stan- dard deviations (SD) of the mean (see Chapter 1.3.1). In a particular individual, intakes above the reference nutrient intake are almost certainly ade- quate, unless there are very high disease-induced requirements for specific nutrients, while intakes below the lower reference nutrient intake are al- most certainly inadequate.
Taking a Feeding History
A careful history is an important component of nutritional assessment. Listed below are some of the questions and ‘cross-checks’ that are integral to an accurate feeding/diet history:
Infant: is the baby being breastfed or formula fed?
For breastfed infants:
• How often is the baby being fed and for how long on each breast? Check positioning and technique
• Are supplementary bottles or other foods of- fered?
For formula-fed infants:
• What type of formula? How is the feed made up? i.e. establish the final energy content/
100 ml
• Is each feed freshly prepared?
• How many feeds are taken over 24 h?
• How often are feeds offered: every 2, 3 or 4 h?
• What is the volume of feed offered each time?
• How much feed is taken?
• How long does this take?
• Is anything else being added to the bottle?
For older children:
• How many meals and snacks are eaten each day?
• What does your child eat at each meal and snack (obtain 1- or 2-day sample meal pat- tern)
• How do the parents describe their child’s ap- petite?
• Where does the child eat meals?
• Are there family mealtimes?
• Are these happy and enjoyable situations?
• How much milk does the child drink?
• How much juice does the child drink?
• How often are snacks/snack foods eaten?
(Further details are provided in Chapter 1.2.2.)
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Basic Anthropometry: Assessment of Body Form
Accurate measurement and charting of weight and height (‘length’ in children <85 cm, or un- able to stand) is essential if malnutrition is to be identified; clinical examination without charting anthropometric measurements (‘eye-balling’) has been shown to be very inaccurate [5] . For premature infants up to 2 years of age, it is es- sential to deduct the number of weeks born ear- ly from actual (‘chronological’) age in order to derive the ‘corrected’ age for plotting on growth charts. Head circumference should be routinely measured and plotted in children less than 2
years old. Measurements should be made as fol- lows:
Weight:
• Weigh infants less than 2 years old naked • Weigh older children only in light clothing
( fig. 1 )
• Use self-calibrating or regularly calibrated scales
Length:
• If possible, use an infant measuring board, measuring mat (easily rolled and transported) or a measuring rod (www.gosh.nhs.uk/health- professionals/clinical-guidelines/height-mea- suring-a-child/#Rationale)
• Two people are required to use the measuring board: one person holds the head against the headboard while the other straightens the knees and holds the feet flat against the move- able footboard ( fig. 2 )
Height:
• Use a stadiometer if possible ( fig. 3 ), a device for standing height measurement comprising a vertical scale with a sliding horizontal board or arm that is adjusted to rest on top of the head
• Remove the child’s shoes
• Ask the child to look straight ahead
• Ensure that the heels, buttocks and shoulder blades make contact with the wall
Fig. 1. Weigh older children only in light clothing using regularly maintained and calibrated scales.
Fig. 2. An infant measuring board; two people are re- quired for accurate determination of length.
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 6–13 DOI: 10.1159/000360311
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Head circumference:
• Use a tape measure that does not stretch • Find the largest measurement around the mid
forehead and occipital prominence
Mid-upper-arm circumference:
• Mark the mid upper arm (halfway between the acromion of the shoulder and the olecranon of
the elbow; fig. 4 ), then use a non-stretch tape measure and take the average of 3 readings at the midpoint of the upper arm ( fig. 5 )
Skinfold thickness:
• Pinch the skin between two fingers and apply specialised skinfold callipers ( fig. 6 ); experi- ence is needed to produce accurate and repeat-
Fig. 3. A stadiometer should be used for accurate assessment of height.
Fig. 4. The mid upper arm is the point halfway between the acromi- on of the shoulder and the olecra- non of the elbow (marked with a pen).
Fig. 5. To determine mid-upper-arm circumference, take the average of 3 readings made with a non-stretch tape measure at the mid-upper-arm point.
4 5
10 Puntis
able measurements (http://healthsciences.
qmuc.ac.uk/labweb/Equipment/skin_fold_
calipers.htm); take triceps skinfold thickness readings at the mid upper arm using the re- laxed non-dominant arm; the layer of skin and subcutaneous tissue is pulled away from the underlying muscle, and readings are taken to 0.5 mm, 3 s after the application of the calli- pers; measurements can also be taken at oth - er sites (www.cdc.gov/nchs/data/nnyfs/Body_
Measures.pdf)
Growth
Growth rate in infancy is a continuation of the intrauterine growth curve, and is rapidly deceler- ating up to 3 years of age. Growth in childhood is along a steady and slowly decelerating growth curve that continues until puberty, a phase of growth lasting from adolescence onwards. Dur- ing puberty, the major sex differences in height are established, with a final height difference of around 12.5 cm between males and females.
Growth charts are derived from measurements of many different children at different ages (cross- sectional data). Data on growth of children are distributed ‘normally’ (i.e. they form a ‘bell-
shaped’ curve). These data can be expressed mathematically as mean and SD from the mean.
The centile lines delineate data into percentages:
the 50th centile represents the mean (average);
25% of children are below the 25th centile. The normal range (approx. ±2 SD from the mean) lies between the 3rd and the 97th centile.
Normal Growth: Simple Rules of Thumb Approximate average expected weight gain for a healthy term infant:
• 200 g/week in the first 3 months • 130 g/week in the second 3 months • 85 g/week in the third 3 months • 75 g/week in the fourth 3 months
• Birth weight usually doubles by 4 months and triples by 12 months
Length:
• Increases by 25 cm in the first year • Increases by 12 cm in the second year • By 2 years, roughly half the adult height is at-
tained
Head circumference:
• Increases by 1 cm/month in the first year • Increases by 2 cm in the whole of the second
year
• Will be 80% of adult size by 2 years
(N.B.: growth rates vary considerably between children; these figures should be used in con- junction with growth charts.)
Patterns of Growth
Birth weight/centile is not always a good guide to genetic potential; some infants cross centile lines in the first few months of life (‘catch down’), but from then on continue to follow along a lower centile. The maximum weight centile achieved between 4 and 8 weeks is the best predictor of weight centile at 12 months. Infants born below the 10th centile for gestational age may either
Fig. 6. Triceps skinfold thickness taken with Harpenden callipers at the mid upper arm allows estimation of fat energy stores and is useful for serial monitoring.
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 6–13 DOI: 10.1159/000360311
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have intrauterine growth retardation (IUGR) or be within the normal 10% of the population who fall below this line. Long-standing IUGR results in low weight, head circumference and length (‘symmetrically’ small); catch-up growth is un- likely. Infants with late IUGR are thin but may have head circumference and length on a higher centile, and subsequently show catch-up in weight. It should be noted that rates of growth vary in young children, and assessments should be based on serial measurements. A short-term energy deficit will make a child thin (low weight- for-height = wasting). A long-term energy deficit limits height gain (and head/brain growth), caus- ing stunting. Children who are chronically un- dernourished may be both thin and short.
Assessment of linear growth potential:
• Plot the height of both parents at the 18-year- old end of the centile chart
• Add together parental heights and divide by 2
• Add 7 cm (male child) or subtract 7 cm (fe- male) = mid parental height; mid parental height ± 8.5 cm (girl) or ± 10 cm (boy) = target height centile range
Anthropometric Indices and Definitions of Malnutrition
Weight-for-height compares a child’s weight with the average weight of children of the same height, i.e. the actual weight/weight-for-height at the 50th centile – for example, a 2.5-year-old girl with height = 88 cm and weight = 9 kg: the 50th-
centile weight of a child who, at 88 cm, is on the 50th centile for height = 12 kg; therefore, weight- for-height = 9/12 = 75% (‘moderate’ malnutri- tion).
Weight-for-height can be expressed either as percent expected weight or as z score. The z score is commonly used when statistical comparisons are made as it enables children of different sexes and ages to be compared. A value on the 50th centile would have a z score of 0, whereas values on the 3rd and 97th centiles would be –2 and +2 SD, respectively. Mid-upper-arm circumference (MUAC) provides a quick population screening tool for malnutrition; reference charts are avail- able [6] . MUAC may also be more appropriate for some children in whom body weight is mislead- ing (e.g. childhood cancer with large tumour mass, liver disease with oedema). WHO stan- dards show that in a well-nourished population there are very few children aged 6–60 months with an MUAC <115 mm; children below this
Table 1. Criteria for malnutrition
Obese Overweight Normal Mild
malnutrition
Moderate malnutrition
Severe malnutrition
Height-for-age, % 90–95 85–90 <85
Weight-for-height, % >120 110–120 90–100 80–90 70–80 <70
BMI >30 >25
Table 2. Wellcome classification of malnutrition Marasmus <60% expected weight-for-age,
no oedema
Marasmic kwashiorkor <60% expected weight-for-age, oedema present
Kwashiorkor <60–80% expected weight-for- age, oedema present
Underweight <60–80% expected weigh-for- age, no oedema
12 Puntis
cut-off have a highly elevated risk of death [7] . BMI is derived from weight in kilograms divided by the square of the height in metres (kg/m 2 ); it is an alternative to ‘weight-for-height’ as an assess- ment of nutritional status [8] . In a mixed popula- tion of hospital inpatients there will be only a slight difference in malnutrition prevalence us- ing the SD score for either BMI or weight-for- height.
Classifications of Malnutrition
There is no single, universally agreed definition of malnutrition in children [9, 10] , but the criteria shown in table 1 are commonly used. The classi- fication does not define a specific disease, but rather clinical signs that may have different aeti- ologies. Other nutrients such as iron, zinc and copper may be deficient in addition to protein and energy.
The Wellcome classification of malnutrition is based on the presence or absence of oedema and the body weight deficit ( table 2 ). Severe acute malnutrition in children aged 6–60 months is now defined by the WHO as weight-for-height below –3 SD or MUAC below 115 mm [7] .
When to Intervene
Malnutrition is a continuum that starts with a nu- trient intake inadequate to meet physiological re- quirements, followed by metabolic and function- al alterations and, in due course, by impairment of body composition. Malnutrition is difficult to define and assess because of insensitive assess- ment tools and the challenges of separating the impact of malnutrition from that of the underly- ing disease on markers of malnutrition (e.g. hy- poalbuminemia is a marker of both malnutrition and severe inflammation) and on outcome. Nu- tritional intervention may be indicated both to prevent and to reverse malnutrition. In general,
the simplest intervention should be followed, if necessary, by those of increasing complexity. For example, energy-dense foods and calorie supple- ments before progressing to tube feeding (see Chapter 3.3). Parenteral nutrition should be re- served for children whose nutrient needs cannot be met by enteral feeding (see Chapter 3.4). When simple measures aimed at increasing energy in- take by mouth are ineffective, tube feeding should be considered [11] ; the following are suggested criteria [12] :
• Inadequate growth or weight gain over >1 month in a child aged <2 years
• Weight loss or no weight gain for >3 months in a child aged >2 years
• Change in weight-for-age of more than –1 SD within 3 months for children aged <1 year • Change in weight-for-height of more than –1
SD within 3 months for children aged >1 year • Decrease in height velocity of 0.5–1 SD/year at an age <4 years, and of 0.25 SD/year at an age
>4 years
• Decrease in height velocity of >2 cm from the preceding year during midpuberty
Conclusions
• A detailed feeding history should be part of routine nutritional assessment
• Expert dietetic assistance is required for more objective assessment of nutritional intake, and for appropriate further management
• Accurate assessment of growth by careful measurement and reference to standard growth charts is essential to define and moni- tor nutritional status
• Malnutrition is a dynamic and complex pro- cess, without clearly agreed definitions
• The clinical status and particular needs of each individual child require careful evalua- tion when planning nutritional support
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 6–13 DOI: 10.1159/000360311
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9 Raynor P, Rudolf MCJ: Anthropometric indices of failure to thrive. Arch Dis Child 2000; 82: 364–365.
10 Puntis JWL: Malnutrition and growth.
J Pediatr Gastroenterol Nutr 2010;
51:S125–S126.
11 Braegger C, Decsi T, Dias JA, et al: Prac- tical approach to paediatric enteral nutrition: a comment by the ESPGHAN Committee on Nutrition. J Pediatr Gastroenterol Nutr 2010; 51: 110–122.
12 Joosten KFM, Hulst JM: Malnutrition in pediatric hospital patients: current issues. Nutrition 2011; 27: 133–137.
References
1 Olsen IE, Mascarenhas MR, Stallings VA: Clinical assessment of nutritional status; in Walker WA, Watkins JB, Duggan C (eds): Nutrition in Pediatrics.
London, Decker, 2005, pp 6–16.
2 Wright CM: The use and interpretation of growth charts. Curr Paediatr 2002; 12:
279–282.
3 Brook C: Determination of body compo- sition of children from skinfold mea- surements. Arch Dis Child 1971; 46: 182–
184.
4 British Nutrition Foundation: Nutrient requirements. 2014. www.nutrition.org.
uk/nutritionscience/nutrients/nutrient- requirements.
5 Cross JH, Holden C, MacDonald A, Pearmain G, Stevens MC, Booth IW:
Clinical examination compared with anthropometry in evaluating nutritional status. Arch Dis Child 1995; 72: 60–61.
6 Frisancho AR: New norms of upper limb fat and muscle areas for assessment of nutritional status. Am J Clin Nutr 1981;
34: 2540–2545.
7 WHO: The WHO child growth stan- dards. 2006. www.who.int/childgrowth/
standards.
8 Hall DMB, Cole TJ: What use is the BMI? Arch Dis Child 2006; 91: 283–286.
1 Specific Aspects of Childhood Nutrition
Key Words
Assessment of an individual child ã Barriers to intake ã Barriers to absorption ã Detailed diet history ã Tailored advice ã Monitoring
Key Messages
• Assessment of dietary intake is essential in under- standing the nutritional status of an individual child • Assessment of the barriers to intake and absorption
is integral to this process
• Assess food and drink intake in the individual child by taking a detailed dietary history, usually from the parent and child together
• Use information gained to tailor treatment and ad- vice
• This is a skilled job requiring training to perform and expertise to interpret; use a dietician or experi- enced clinician, if possible © 2015 S. Karger AG, Basel
Introduction
This chapter will deal with methods to use for the assessment of an individual child who has pre- sented with a problem that may have a dietary origin. The fact that we are dealing with an indi- vidual child in need of diagnosis and treatment
or advice dictates the methods to be used. In as- sessing the nutritional status of a child, it is im- portant to ascertain whether their likely needs are being covered by their dietary intake. This will include the assessment of any barriers to intake or absorption of nutrients from the foods con- sumed.
For children below the age of 8–10 years (de- pending on the individual child’s maturity), par- ents or caregivers will be the main source of reli- able information. Children below this age do not have the cognitive skills necessary to answer questions about foods eaten accurately enough for assessment [1] . Even with older children, it is best to obtain corroboration and expansion of child- supplied information from parents, although this process needs careful handling. Interviewing the child and parent together in a collaborative way is probably the way to start. If conflict arises at this stage, this may be an important indicator of the source of any dietary problems found.
To carry out this process is a skilled job re- quiring a high level of expertise to achieve the desired result of discovering the presence of like- ly dietary problems and to formulate recommen- dations for improvement. If available, a dietician will have the training and expertise to carry out
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 14–18 DOI: 10.1159/000367877
1.2 Nutritional Assessment