Trends and determinants of anemia in children 6–59 months and women of reproductive age in Chad from 2016 to 2021

Abstract Background Hemoglobin assessments in children and women have been conducted annually in Chad since 2016 through the Standardized Monitoring and Assessment of Relief and Transitions (SMART) cross-sectional surveys. This analysis aims to characterize national and sub-national trends in anemia among children under five and women of reproductive age from 2016 to 2021 and to compare risk factors for anemia before and during the COVID-19 pandemic. Methods Hemoglobin concentrations were measured in approximately half of the 12,000 to 15,000 included households each year, except for 2020 when hemoglobin tests were omitted. For children 6 to 59 months of age, anemia was defined as hemoglobin less than 11.0 g/dL. Anemia was defined as hemoglobin less than 11.0 g/dL and 12.0 g/dL for pregnant women and non-pregnant women, respectively. Trends were stratified by agroecological zone, and tests of proportions were used to assess statistical significance. Simple and multivariate logistic regression models were conducted for 2019 and 2021 to identify risk factors for anemia. Results Reductions in anemia over the 6-year period were significant among women (47.6–30.8%, p = 0.000) and children (68.6–59.6%, p = 0.000). The Sudanian zone had consistently higher rates, particularly in children, compared to the Sahelian and Saharan zones. Significant declines in women’s anemia were observed in all zones from 2019 to 2021, but this global decline was not observed among children, where rates in the Saharan zone significantly increased. In 2019, only minimum dietary diversity significantly reduced the odds of anemia in children (AOR: 0.65, 95%CI: 0.46–0.92), whereas in 2021, improvements in all diet indicators were associated with lower odds of anemia. Improved household socio-economic factors, including head of household literacy, were associated with lower odds of anemia in children (2019 AOR: 0.76, 95%CI: 0.67, 0.88) and women (2019 AOR: 0.75, 95%CI: 0.65, 0.87; 2021 AOR: 0.81, 95%CI: 0.70, 0.93). Conclusions Anemia declined significantly in Chad among women of reproductive age and children from 2016 to 2021, but the national prevalence of 60% among children remains unacceptably high. Sub-national differences in anemia rates underline the need to identify and address regional causes of anemia while strengthening national level programs.