Should we use WFH or MUAC as admission criteria in CTC

1
Should we use WFH or MUAC as admission criteria
in CTC ?

• André Briend
• World Health Organization,
• Child and Adolescent Health and Development,
  Geneva
• brienda_at_who.int

2
How to select a nutritional index as admission
criteria for CTC ?

• 1- Compare indices to a golden standard
• 2- Compare prognostic value
• 3- Compare response to treatment of selected
  children
• 4- Do a risk benefit analysis of
  misclassifications
• 5- Looking for maximum performance of CTC

3
1- Compare indices to a "gold standard"

• Good approach use as "gold standard" a reliable
  measure of nutritional status
• Wrong approach take one of the indices as "gold
  standard".
• MUAC often rejected because it poorly correlates
  with WFH considered as "gold standard".
• NONSENSE !!!

4
What do we want to measure ?

• Physiology nutritional status RATIO between
  NUTRIENT RESERVES (MUSCLE and fat) and nutrient
  requirements of ORGANS (BRAIN, liver, heart,
  kidney)
• Special role of muscle as nutrient reserve during
  infections
• Nutrient reserves in muscle 4 body weight in
  children (20 of 20 body weight)
• Weight for height relationship between body
  weight (96 unrelated to nutrient reserves) and
  height (very remotely related to nutrient
  requirements of organs)
• MUAC more directly related to muscle mass (still
  80water)

5
Using body composition as "gold standard"

• Only 1 study looked at anthropometry vs body
  composition
• Brambilla et al. Lean mass of children in various
  nutritional states. Comparison between
  dual-energy X-ray absorptiometry and
  anthropometry. Ann N Y Acad Sci. 2000
  May904433-6.
• Gold standard ratio lean mass (arms
  legs)/trunk
• Children aged 4-11 years, 10 celiac disease, 10
  healthy thin, 41 normal and 39 obese.

6
Correlation between different nutritional indices
with the lean mass ratio (arms legs)/trunk
MUAC more closely correlated with measures of
body composition by DEXA than other indices
Brambilla et al. Ann NY Acad Sc, 2000
7
Discussion of the DEXA study

• Limitations
• Age group (4-11 years) different from children
  seen in CTC, some obese children
• Main conclusion
• MUAC may better reflect body composition than WFH

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2- Compare the prognostic value
Sensitivity a/(ac) Specificty d/(bd) False
positive 1- Specificity
9
ROC curve of different nutritional indices to
assess the risk of dying in rural Senegal
1- MUAC 2- WFA 3- WFH 4- HFA
Briend et al, Eur J Clin Nutr 1989
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Result of the study comparing indices to assess
the risk of dying

• MUAC is usually among the best indices, if not
  the best, often superior to WFH
• Correcting MUAC for age or height does not
  improve the quality of the prediction

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Why MUAC is superior to assess the risk of dying ?

• Relationship with body composition and muscle
  mass (see above)
• Age effect MUAC increases with age, and a fixed
  cut off automatically selects younger children
• Both explanations are compatible malnutrition
  gives the body composition of a younger child
  (lower muscle / organ ratio)

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Age effect
MUAC selects preferentially YOUNG malnourished
children, at higher risk of death DO NOT CORRECT
MUAC FOR AGE
ENN Infant feeding in emergency
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3- Compare response to treatment

• Weight gain seems related to WFH on admission
• Young children with low MUAC but moderate wasting
  usually have moderate weight gain
• Rationale for not using MUAC for admission in a
  TFC, especially for the 6-12 months

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4- Compare risks and benefits of MUAC and WFH

• No system of selection of malnourished children
  is perfect, whatever selection criteria is used
• Whether MUAC or WFH is used, risk benefits of
  admission or rejection for treatment should also
  be made

15
4- Risk benefits of selection with WFH and MUAC
in a TFC
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4- Risk benefits of selection with WFH and MUAC
with CTC
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Will use of MUAC result in higher patient load
and higher programmes costs ?

• OPEN QUESTION
• Young children with low MUAC and high WFH will be
  "added" to the program
• BUT
• Older children with high MUAC, low WFH will not
  be included
• REMARK
• Use of both criteria (low WFH OR low MUAC) will
  increase patient load

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5- Looking for maximum performance indicators of
CTC

• MUAC selects younger children with higher
  mortality and lower weight gain
• Objective of the program ?
• "Looking good" have good weight gain, low
  mortality WITHIN the program ? GO FOR WFH
• "Doing good" target vulnerable children, have an
  impact on OVERALL mortality ? GO FOR MUAC
• Note "Doing good option" may cost a bit more
  need to brief donors

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Conclusions

• The choice between MUAC and WFH will depend on
  whether we give greater importance to the
  assessment of the risk of death or to the
  response to treatment
• However, CTC changes the risk benefit matrix.
• Need to reconsider the current use of WFH as
  admission criteria in CTC programmes Selection
  by MUAC seems more adapted to CTC.

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Last argument in favor of WFH

• Warum es einfach machen wenn es auch kompliziert
  geht ???
• German proverb