Concurrent wasting and stunting among children 6-59 months: an analysis using district-level survey data in Mozambique

Background: In the past it was believed that wasting and stunting were independent of each other. Recent work has shown that they can occur concurrently in a child and that increases considerably the risk of mortality. Concurrent wasting and stunting (WaSt) is currently defined as WHZ < -2 AND HAZ < -2. Wasting is measured by WHZ and MUAC and evidence shows that they tend to identify different sets of children. Our study aimed to look at the effect of adding MUAC on the prevalence and burden of WaSt, and to assess diagnosis of WaSt with a single measurement.

Methods: We analyzed population-based anthropometric surveys from 37 districts in Mozambique conducted by the Government of Mozambique between 2017 and 2019. We proposed a new case-definition for WaSt that includes MUAC in acknowledgement of the different children with wasting diagnosed by WHZ and MUAC. We estimated how many WaSt cases are eligible to be included in the existing treatment program in Mozambique by calculating the True Positive and False Positive Values of WaSt using our proposed case-definition against the wasting admission criteria. AUC of ROC curves used for MUAC and WAZ and optimal cut-offs were determined using Youden's Index.

Results: Including MUAC in the concurrent WaSt case-definition identified more children with WaSt compared to the original case-definition and more younger children and girls were identified. Using both MUAC and WHZ and enrolling severe and moderate wasting is already picking up most of the WaSt cases: 100% in health facilities and 79.40% with MUAC mass screenings at community level. Cut-off values from the ROC curve for the proposed case-definition were MUAC ≤133 mm and WAZ ≤ 2.145 Z-scores, however, they yielded many false positive values.

Conclusion: WaSt case-definition should include MUAC. WaSt should commence to be reported in surveys and Mozambique should also start monitoring and treating children with WaSt. A cost-effective approach to identify all children with WaSt without adding too many false positive is needed, as well as understanding how to achieve optimal treatment outcomes within existing programs.