Identifying territorial inequalities in the population-level double burden of child malnutrition in Argentina: A...

The double burden of malnutrition (DBM) at the population level, the coexistence of undernutrition and overnutrition within the same region, is a growing public health challenge in many low- and middle-income countries. Historically, its components (i.e. stunting and overweight) have been analysed independently, limiting the identification of overlapping spatial patterns. We studied territorial inequalities in population-level DBM among children under five in Argentina by jointly modelling the spatial distribution of stunting and overweight. We conducted a cross-sectional study using 2019 anthropometric data from 970,516 children under five with public healthcare coverage across 513 departments. Stunting and overweight were defined using the WHO growth standards. Bayesian spatial joint models were fitted under the INLA framework, studying structures with independent and shared spatial effects for each outcome. The mean departmental proportions were 11.4 % for stunting and 14.2 % for overweight, with geographic location explaining 55.0 % and 41.7 % of their respective variances. The shared spatial structure accounted for 47.9 % of the total random variation. Departments with the highest DBM proportion were located in southwestern Patagonia and the Central and Northern region. This study provides the first department-level mapping of DBM in Argentina, providing a comprehensive view of its spatial distribution while simultaneously estimating the distinct spatial patterns of each indicator. These findings are essential for identifying high-risk areas and guiding integrated strategies to reduce inequalities. Although limited to children with public coverage and potentially introducing ecological bias, the departmental scale likely mitigated these issues, yielding robust, policy-relevant estimates.