Childhood undernutrition mediates the relationship between open defecation with anemia among Ethiopian children: a nationally representative cross-sectional study

Abstract Background Poor sanitation and/or open defecation are a significant public health problem in Ethiopia, where access to improved sanitation facilities is still limited. There is a growing body of literature about the effect of open defecation on children’s linear growth failure. However, very few studies about the effects of open defecation on child anemia exist. In this study, we examine whether childhood undernutrition (i.e. stunting, wasting, and underweight) mediates the relationship between open defecation and childhood anemia in children aged 6–59 months in Ethiopia. Methods We used pooled Ethiopia Demographic and Health Survey data (2005–2016) comprising 21,918 (weighted data) children aged 6–59 months. Anemia was defined as an altitude-adjusted hemoglobin (Hb) level of less than 11 g/deciliter (g/dl) for children under 5 years. Childhood undernutrition was assessed using height-for-age Z-scores (HAZ), weight-for-age Z-scores (WAZ), and weight-for-height Z-scores (WHZ) for stunting, wasting, and underweight respectively. Mediation effects were calculated using the bootstrap and the indirect effect was considered significant when the 95% bootstrap confidence intervals (95% CI) did not contain zero. Moreover, separate multilevel regression analyses were used to explore the statistical association between open defecation and child anemia, after adjusting for potential confounders. Results Our analysis revealed that nearly half (49.6%) of children aged 6 to 59 months were anemic, 46.8% were stunted, 9.9% were wasted, and 29.5% were underweight. Additionally, 45.1% of children belonged to households that practiced open defecation (OD). Open defecation was associated with anemia (AOR: 1.28; 95% CI: 1.18–1.39) and it positively predicted anemia with direct effect of β = 0.233, p < 0.001. Childhood undernutrition showed a partial mediating role in the relationship between OD and anemia. Analyzing the indirect effects, results revealed that child undernutrition significantly mediated the relationship between open defecation and anemia (stunting (βindirect = 0.014, p < 0.001), wasting (βindirect = 0.009, p = 0.002), and underweight (βindirect = 0.012, p < 0.001)). When the mediating role of child undernutrition was accounted for, open defecation had a positive impact on anemia with a total effect of βtotal = 0.285, p < 0.001. Conclusion Open defecation showed a significant direct effect on anemia. Child undernutrition remarkably mediated the relationship between OD and anemia that further magnified the effect. This finding has an important programmatic implication calling for strengthened, accelerated and large-scale implementation of strategies to end open defecation and achieve universal access to sanitation in Ethiopia.