Factors associated with anemia among school-going adolescents aged 10-17 years in Zanzibar, Tanzania: a cross sectional study.

BACKGROUND: Anemia among adolescents (ages 10-19 years) is a leading cause of morbidity and mortality in low- and middle-income countries and carries long-term health and economic consequences. To address the issue, policymakers and programmers require evidence of the burden of anemia among adolescents in specific contexts, as well as an understanding of the factors associated with anemia in this population. METHODS: We conducted a cross-sectional survey as a baseline assessment to determine the prevalence and factors associated with anemia in secondary school students, as part of a cluster-randomized effectiveness trial testing different micronutrient supplementation strategies in addressing anemia among adolescents in Zanzibar. Between March 7th to 25th, 2022 the survey was conducted on 2,479 school-going adolescents aged 10-17 years from 42 schools on the island of Zanzibar, Tanzania. Hemoglobin concentration was measured along with the collection of socio-demographics, health, food frequency, and water, sanitation and hygiene data. RESULTS: Based on the World Health Organization cutoffs for anemia, 53.3% of the sample had anemia (mild, moderate, or severe). Using chi-square tests and logistic regressions, we determined that females had higher odds of anemia than males (Adjusted OR = 1.47; 95% CI: 1.24, 1.74), those in the highest wealth quintile had lower odds of anemia than those in the lowest wealth quintile (Adjusted OR = 0.7; CI: 0.54, 0.91), stunted adolescents had higher odds of anemia than non-stunted students (Adjusted OR = 1.38; 95% CI: 1.06,1.81), and those who used shared toilets had higher odds of moderate or severe anemia than those with private toilet access (Adjusted OR = 1.68; CI: 1.07, 2.64). CONCLUSIONS: The high prevalence of anemia in this sample indicates an urgent need to address anemia among adolescents in Zanzibar, and the factors associated with anemia point to the importance of water, sanitation, and hygiene interventions in addition to dietary and nutritional support. TRIAL REGISTRATION: NCT05104554, registered 03/11/2021.

Scaling-up high-impact micronutrient supplementation interventions to improve adolescents' nutrition and health in Burkina Faso and Tanzania: protocol for a cluster-randomised controlled trial.

INTRODUCTION: Adolescence is a critical time for growth and development, but this age group is often neglected in research and development of nutrition interventions. Despite recommendations from the WHO to provide nutrient supplements to adolescents, evidence remains scarce on the most effective supplementation strategy. This study aims to compare weekly iron and folic acid (IFA) supplementation with daily multiple micronutrient supplements (MMSs) in prevention of anaemia and improvement of school outcomes among adolescents in Burkina Faso and Tanzania. METHODS AND ANALYSIS: A three-arm cluster-randomised, school-based supplementation trial will be conducted among 84 schools (42 schools per site) and roughly 4500 students aged 10-17. Schools will be matched on three characteristics: number of students, school ranking profile, distance to main road (Tanzania) or distance to city council (Burkina Faso). Each school will be randomised to receive either weekly IFA, daily MMSs or serve as a control. Supplements will be delivered to students by teachers, who will provide monitoring data to the study team. Baseline and endline surveys will be conducted prior to and after each supplementation cycle (12 weeks in Burkina Faso; 1 year in Tanzania) to assess haemoglobin, anthropometry and sociodemographic variables. The primary outcome of haemoglobin will be analysed continuously using linear regression, and anaemia status will be analysed using logistic or multinomial regression, depending on categorisation level of the outcome. Secondary analyses of school performance indicators will also be conducted with either logistic or linear regression. ETHICS AND DISSEMINATION: This protocol has been approved by the Institutional Review Board of the Harvard TH Chan School of Public Health (IRB20-1108) and the Research Ethics Committees for the Ministries of Health in Tanzania (Zanzibar) and Burkina Faso. Results will be disseminated during meetings with the Ministries of Health and the participating communities as well as through peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT04657640; NCT05104554.