Variation in time and sensitivity of Anthropometric measures of MUAC and WFH/WFL z-score for screening, admission to follow up and discharge of moderately malnourished children 6-59months on supplementary feeding program
Amegovu Kiri Andrew, Michael Mawadri, Timothy chewere, Irumba Joseph
Under nutrition is a direct causal factor of more than half of child mortality globally, reduces human productivity and cripples national economy by an estimated 10%. It is therefore imperative that malnourished children are identified and enrolled on to rehabilitation programmes. WHO recommends the use of Weight-for-Length (WLZ)/Weight-for-Height (WHZ) and Mid Upper Arm Circumference (MUAC) for the assessment of nutritional status in children. However, results from these two anthropometric measures often differ; only a proportion, 40% of malnourished children identified by one of the indicators is also identified by the other. There is also a discrepancy in the prediction of recovery, thus the follow-up time between the two indicators. Therefore, this study investigated the variation in time and error margin in the use of MUAC and WHZ for the admission, follow up and discharge of moderately malnourished (MAM) preschool children on supplementary feeding program. This was a prospective cohort study and was conducted from September 2015 to November 2015 in Moroto district, Karamoja region, North Eastern Uganda. A total of 181 MAM preschool children were recruited and followed up. MAM cases were screened in the villages using MUAC (11.5 to 12.5 cm) by VHTs who referred them to 14 different sites. At these sites, trained nutritionist rescreened the children based on MUAC and W/H criteria. Participants were provided with super cereal plus ration on a biweekly basis obtained from WFP. They were followed up weekly using MUAC and WHZ until discharge for maximum of 90 days. During follow-up, both MUAC and W/H measurements were done on each participant at each visit to determine which criterion participants responded to first. Kaplan Meir Survival analysis was done to ascertain the differences in recovery time. On admission, all the 181 participant qualified as MAM cases with MUAC >11.5cm and <12.5cm as per WHO guideline. However, on using WLZ/WHZ in z-score, 56.4% did not qualify as MAM cases as their WHZ-score is >-2SD. Only 33.7% qualified as MAM and 9.9% as Severe Acute Malnutrition (SAM) implying high sensitivity but low specificity of MUAC in identifying MAM cases during screening. The error margin or difference of 56.4% between MUAC and WHZ measure for admission could be a result of confounding by other factors such as age, ethnicity, sex, and stunting which this study did not investigate. There was no significant difference (p>0.05) in time taken on using MUAC and WHZ-score for the follow up of MAM cases admitted into SFP until discharge. Based on MUAC criteria, 59% (71/120) of the followed up participants, reached the recovery cutoff point while based on W/H criterion, only 41% (9/120) reached the recovery discharge cutoff. This equally shows MUAC as a good measure for discharge as it is for admission. There was a similarity between the average length of stay (LOS), 43 days from admission to recovery using either MUAC or WHZ. The use of MUAC as a stand-alone anthropometric measure could be recommended for admission, follow up and discharge into nutritional rehabilitation programs for MAM.