Factors associated with stunting among children 0 to 59 months of age in Angola: A cross-sectional study using the 2015-2016 Demographic and Health Survey

Abstract

Stunting among children under five years of age is a serious public health problem globally, with life-long consequences to health, well-being, and productivity. Stunted growth has complex and multifactorial causes, reflecting the interaction of a broad range of conditions that determine child health. The Angola 2015-2016 Demographic and Health Survey (DHS) collected nationally representative anthropometry for 6,359 children 0 to 59 months of age in Angola, and ascertained exposure to a wide range of child, parental, socio-economic, and geographic variables. This study used a cross-sectional design to identify exposures associated with stunting among children 0 to 59 months of age in Angola, while considering the multifactorial and multi-level causes of stunting. Main outcome was prevalence of stunting, defined as proportion of children with height-for-age Z-score (HAZ) two or more standard deviations below the median. Prevalence of stunting was associated with individual, household, and area-level exposure variables, including child age and sex, birth order, birthweight, diarrhea, maternal and paternal age and education, source of water, sanitary system, and province. In conclusion, prevalence of stunting in Angola is associated with several factors previously described in the literature. Stunting is associated with exposures at the distal, intermediate, and proximal levels, in line with the framework on the causes of childhood malnutrition. This study identifies opportunities for interventions at multiple levels to decrease prevalence of stunting among children in Angola. Main limitations of this study are the potential for survival bias and residual confounding.

Fig 1. Sampling procedure used in the Angola 2015–2016 Demographic and Health Survey (DHS).

Flowchart describing sampling procedure, including stratification, stages of selection of sampling units, methods of sampling used, and number of households selected. ¹Each subset of the primary sample is equally representative of the main sample and of the country population. ² Census sections have an average of 83 households (103 in urban areas, and 63 in rural areas). Census sections with less than 30 households were combined to form secondary sampling units (SSUs) with at least 30 households. ³ Sampling resulted in 33 SSUs per province, except Luanda, where 66 SSUs were sampled; 345 SSUs were in urban areas, and 282 in rural areas.

Fig 2. Map of the Republic of Angola displaying prevalence of stunting by province.

Map shows the territory of the Republic of Angola with the 18 provinces color-coded according to prevalence of stunting among children 0 to 59 months of age estimated in the Angola 2015–2016 DHS (Table 1). Base layer map shapefile was obtained from GADM (https://gadm.org/maps/AGO.html) [40]. Terms and conditions of use available from https://gadm.org/license.html.

Fig 3. Map of the Republic of Angola displaying prevalence ratio of stunting for each province relative to Luanda.

Map shows the territory of the Republic of Angola with the 18 provinces color-coded to display adjusted prevalence ratio of stunting among children 0 to 59 months of age relative to Luanda. Adjusted prevalence ratios were obtained using fixed-effects multivariable Poisson regression model 3 (Table 2). Base layer map shapefile was obtained from GADM (https://gadm.org/maps/AGO.html) [40]. Terms and conditions of use available from https://gadm.org/license.html.