If the BMI is indicator that measures underweight in adults, what are the indicators that conventient for measuring wasting and stunting in adults?
WH and HA Z-Score, they are statistically proven. But the problem is that the reference values are still the NCHS ones. I have no Idea, if WHO has developed some country specific for the adults. The NCHS reference values for adults are, though, applicable for most of the countries, however, they are controversial for children under five.
Thanks.
Tariq Khan
Answered:
10 years agoThanks.
Atif
Answered:
10 years agoBMI is not a good indicator because (1) it is (unless corrected) severely affected by body shape; (2) it is difficult to apply to older people, disabled people, people with difficult standing, and pregnant / lactating women; (3) you need to account for oedema / ascites; (4) height varies throughout day and the 'height-squared' term amplified this variation; and (5) height varies naturally with age meaning that the sensitivity of BMI thresholds reduces with increasing age (i.e. increasing vulnerability). BMI should probably be limited to population-level assessments of chronic undernutrition in within-population before and after assessments. Note that BMI is a W/H measures and all W/H measures have the same problems.
You have to be careful using termes from childhood malnutrition such as "stunting" and "wasting". The absence of linear growth in adults (it reaches a peak in early adulthood and subsequently declines at about 1.25 cm / decade) means that "stunting" (a process) is "stuntedness" (an outcome) that cannot be corrected but gets "worse" (only apparently) because of age-related height loss. All this means that measuring H/A is measuring an type of "lagging indicator" (i.e. you measure something that happened as a result of something that happened years or decades previously) ... not very useful if it cannot be treated and cannot (without a time-machine) be prevented.
As you might expect from me ... MUAC is a good indicator. I think this [url=http://www.brixtonhealth.com/RNIS.Adults.pdf]this RNIS report[/url] provides a useful review (I would ... I wrote some of it).
Note : Z-scores are a statistically proven technique but this does not mean that they are practically proven to be applicable to all problems. I prefer indicators that that reflect function and MUAC reflects that better (not fantastically well but better) then BMI, HAZ, WAZ, &c. There are also practical and philosophical problems with the use of reference populations. Indicators designed to represent ideal growth may not be ideal for the purpose of identifying individuals, or populations, requiring emergency nutrition interventions. Proponents of the use of reference populations, in my opinion, tend to mistake "non-ideal" for "pathological".
I hope this is of some use.
Mark Myatt
Technical Expert
Answered:
10 years ago