Omitting edema measurement: how much acute malnutrition are we missing?

BACKGROUND Acute malnutrition is a major public health issue in low-income countries. It includes both wasting and edematous malnutrition, but the terms wasting and acute malnutrition are often used interchangeably. Little is known about the burden of edematous malnutrition, and few large-scale surveys measure it. OBJECTIVE Most acute malnutrition might be captured by the measurement of wasting alone, but this is unknown. This article aims to fill this gap. DESIGN This article presents a secondary data analysis of 852 nutrition cross-sectional survey data sets of children aged 6-59 mo. The data sets assembled included surveys from East, West, South, and Central Africa; the Caribbean; and Asia. The overlap between edematous malnutrition and wasting was assessed, and the impact of including/excluding edema on acute malnutrition prevalence estimates was evaluated. RESULTS The prevalence of edematous malnutrition varied from 0% to 32.9%, and children were more likely to have bilateral edema in Central and South Africa (OR: 4; 95% CI: 2.8, 5.6). A large proportion of children with edematous malnutrition were not wasted [62% and 66% based on midupper arm circumference (MUAC) and weight-for-height (WFH), respectively], and most were not severely wasted (83% and 86% based on MUAC and WFH, respectively). When wasting and global acute malnutrition prevalence estimates as well as severe wasting and severe acute malnutrition prevalence estimates overall were compared, the differences between estimates were small (median of 0.0% and mean of 0.3% based on WFH and MUAC for global estimates and slightly higher median of 0.1% and mean of 0.4% based on MUAC and WFH, respectively, for the severe forms), but the picture was different at the regional level. CONCLUSIONS The terms acute malnutrition and wasting should not be used interchangeably. The omission of the measurement of edema can have important repercussions, especially at the nutrition program level.