Synergistic effects of food insecurity and open defecation on wasting among street children in East Java, Indonesia

Street children in Indonesia face multiple health challenges including malnutrition and poor sanitation. This study aimed to investigate the potential synergistic effect of food insecurity and open defecation on wasting among street children while also considering factors such as self-esteem and inflammation markers. A cross-sectional study was conducted from April to August 2023 in three urban areas of East Java Province, Indonesia, involving 116 street children aged 10–18 years. Wasting was defined as a weight-for-height Z-score (WHZ) below − 2 SDs. Food insecurity, self-esteem, and open defecation behaviors were assessed using standardized scales and questionnaires. The Neutrophil-to-Lymphocyte Ratio (NLR), an inflammation marker, was calculated as the ratio of neutrophils to lymphocytes in blood samples. Data were analyzed using descriptive statistics, Chi-square or Fisher’s exact tests, multiple logistic regression, and additive interaction analysis. The prevalence of wasting was 19.8%. Street children with low self-esteem were significantly more likely to be at risk of wasting than those with high self-esteem (adjusted odds ratio = 4.01; 95% confidence interval = 1.19–13.44). Children with abnormal NLR values had higher odds of being at risk of wasting than those with normal NLR values (adjusted odds ratio = 4.03; 95% confidence interval = 1.46–14.87). Notably, children who were both food insecure and practiced open defecation showed a substantial increase in wasting risk compared with the reference group (adjusted odds ratio = 17.08; 95% confidence interval = 2.98–35.52), demonstrating a significant synergistic effect between these factors. Food insecurity and open defecation were associated with an increased wasting risk among street children, suggesting a synergistic effect. These findings highlight the urgent need for individualized nutritional programs targeting this vulnerable population and addressing both food security and sanitation practices to improve their nutritional status and overall health.