Comparison of Clinical Characteristics and Treatment Outcomes of Children Selected for Treatment of Severe Acute Malnutrition Using Mid Upper Arm Circumference and/or Weight-for-Height Z-Score

Abstract

ObjectivesDebate for a greater role of mid-upper arm circumference (MUAC) measures in nutritional programming continues, but a shift from therapeutic feeding programs admitting children using MUAC and/or weight-for-height Z (WHZ) to a new model admitting children using MUAC only remains complicated by limited information regarding the clinical profile and response to treatment of children selected by MUAC vs. WHZ. To broaden our understanding of how children identified for therapeutic feeding by MUAC and/or WHZ may differ, we aimed to investigate differences between children identified for therapeutic feeding by MUAC and/or WHZ in terms of demographic, anthropometric, clinical, and laboratory and treatment response characteristics.MethodsUsing secondary data from a randomized trial in rural Niger among children with uncomplicated severe acute malnutrition, we compared children that would be admitted to a therapeutic feeding program that used a single anthropometric criterion of MUAC< 115 mm vs. children that are admitted under current admission criteria (WHZ< -3 and/or MUAC< 115 mm) but would be excluded from a program that used a single MUAC< 115 mm admission criterion. We assessed differences between groups using multivariate regression, employing linear regression for continuous outcomes and log-binomial regression for dichotomous outcomes.ResultsWe found no difference in terms of clinical and laboratory characteristics and discharge outcomes evaluated between children that would be included in a MUAC< 115 mm therapeutic feeding program vs. children that are currently eligible for therapeutic feeding but would be excluded from a MUAC-only program.ConclusionsA single anthropometric admission criterion of MUAC < 115 mm did not differentiate well between children in terms of clinical or laboratory measures or program outcomes in this context. If nutritional programming is to use a single MUAC-based criterion for admission to treatment, further research and program experience can help to identify the most appropriate criterion in a broad range of contexts to target children in most urgent need of treatment.

Weight-for-height and mid-upper-arm circumference should be used independently to diagnose acute malnutrition: policy implications

“…Thus, the present data suggest that the two indicators are complementary and additive rather than alternative measures that compete to identify the same individual children at increased risk of death. This is supported by the observation that children with both a deficit in MUAC and WHZ have a worse prognosis that those with a single anthropometric deficit [16]; furthermore addition of other deficits such as a low height-for-age or weight-forage progressively increase the risk of death confirming the additive effect of such deficits [39].…”

“…These analyses show that MUAC has a better sensitivity and specificity than WHZ in predicting subsequent all-cause mortality of the individual child [37]. There are other cogent reasons for favouring MUAC such as its ease of use in the community [16]. However, both low MUAC and low WHZ are associated with an increased risk of subsequent death; albeit at least half the deaths are not related to anthropometric status [1,16,38] and deaths due to accidents such as drowning are more likely in active well-nourished children.…”

“…There are other cogent reasons for favouring MUAC such as its ease of use in the community [16]. However, both low MUAC and low WHZ are associated with an increased risk of subsequent death; albeit at least half the deaths are not related to anthropometric status [1,16,38] and deaths due to accidents such as drowning are more likely in active well-nourished children. The slightly superior power of MUAC to predict which children will die would only be a strong argument for using only MUAC for identification of SAM and GAM children if they were both proxies for the same deficit and predicted the death of the same children.…”

“…Myatt et al explains the lower prevalence using the MUAC criterion in pastoralist communities on this basis [15] and suggests that they are at relatively low risk of death and therefore can safely be excluded from treatment. However, recent evidence indicates that those with deficits in MUAC or WHZ carry the same risk of death, with those with both deficits having a higher risk [16]. On the other hand, because MUAC increases with age, when absolute-MUAC, un-standardised for the size of the child, is used as the criterion younger/smaller children will be more likely to be selected and older children who are also at risk of death may be excluded from treatment.…”

Identifying acute malnutrition – do we have an answer for policy makers?

“…Grellety et al [12] published a study from Sudan indicating that MUAC only identified more severely malnourished children with a higher risk of mortality but failed to identify a third of the children who died. A study by Isanaka et al [13] investigated differences in children identified for therapeutic feeding by MUAC and/or WHT in terms of demographic, anthropometric, clinical, and laboratory and treatment response characteristics and found that using MUAC only identified younger and more female children but did not well differentiate children in terms of other measures of nutritional vulnerability. There are also clear population differences, highlighted by Dasgupta et al [14] in their study when using either MUAC and WHT in India.…”