Prevalence of underweight and its determinants factors among under-five children in Democratic Republic of Congo

Abstract Background Malnutrition is the leading cause of child mortality in developing nations. Underweight children are more vulnerable to infections and impaired cognitive development. Consequently, this research seeks to evaluate the prevalence of underweight and its contributing factors among children under five years in Democratic Republic of Congo. Method Demographic and health survey data from Democratic Republic of Congo was utilized. Our analysis included a total of 6,847 children under the age of 5 years. To determine factors associated with underweight, multilevel binary logistic regression model was applied. Results The prevalence of underweight was 22.22% (95%CI: 21.20, 23.27). Child factors significantly linked to underweight included being male child (AOR = 0.65, 95%CI: 0.57, 0.74), being aged 24 to 59 months (AOR = 4.16, 95%CI: 3.26, 5.30), still breastfeeding (AOR = 1.25, 95%CI: 1.04, 1.50), average birth size (AOR = 0.68; 95% CI: 0.55, 0.84), multiple birth (AOR = 3.09, 95%CI: 2.20, 4.34), experiencing diarrhea (AOR = 1.17, 95%CI: 1.01, 1.37), and fever (AOR = 1.16, 95%CI: 1.01, 1.36) and mother- and household-related factors included normal maternal BMI (AOR = 0.52, 95% CI: 0.44–0.61), access to improved water (AOR = 0.85, 95% CI: 0.72–0.99), higher wealth (AOR = 0.68, 95% CI: 0.54–0.85), and secondary or higher maternal education (AOR = 0.67, 95% CI: 0.56–0.81). Conclusion In Democratic Republic of Congo, prevalence of underweight is notably high. Addressing both child-specific factors such as age, sex, birth size and recent illness and mother/household factors including maternal education, nutritional status, and household wealth index is critical for designing targeted interventions. Therefore, multi-sector strategies to improve child nutrition, including strengthening maternal nutrition programs, supporting multiple-birth households, and integrating WASH interventions in high-poverty areas to tackle this pressing problem in Democratic Republic of Congo.