Association Between Hydration Status, Nutrition, and Cognitive Performance in School‐Age Children in Kumasi, Ghana: A Cross‐Sectional Study

Background Adequate hydration is essential for maintaining good health and optimal cognition in school‐age children. Adequate water intake enhances metabolic and physiological processes, yet school‐age children are vulnerable to dehydration. Aim This cross‐sectional study investigated the associations between hydration status, nutritional anthropometry, and cognitive performance among 200 school‐age children (aged 6–13) in Kumasi, Ghana. Method Ethical approval, parental consent, and child assent were obtained. Hydration status was assessed via urine specific gravity (USG) and categorized as well‐hydrated (USG ≤ 1.010) or dehydrated (USG ≥ 1.011). Nutritional status was evaluated using BMI‐for‐Age Z‐score (BAZ), mid‐upper arm circumference (MUAC), and height‐for‐age Z‐score (HAZ) based on WHO growth reference charts. Cognitive performance was measured using Raven's Colored Progressive Matrices. Linear and binary logistic regressions examined associations between hydration status, nutritional indicators and cognitive performance. Results The sample comprised 37.5% males and 62.5% females. Mean Z‐scores for BAZ (−0.13) and HAZ (−0.11) indicated generally normal growth, though 17.5% of children were overweight/obese and 8.5% were stunted. Notably, 89% of participants were dehydrated, while 70% passed the cognitive test. Multilinear regression revealed an inverse association between BAZ and continuous USG ( β = −0.273, p = 0.005) and a positive association between HAZ and USG ( β = 0.189, p = 0.01). In binary logistic regression, only HAZ remained significantly associated with categorized hydration status (OR = 0.58, 95% CI: 0.36–0.93, p = 0.02). No direct associations were found between hydration status and cognitive performance. Conclusion Dehydration was highly prevalent among school‐age children in Kumasi and was significantly associated with height‐for‐age. These findings emphasize the need for integrated nutrition and hydration assessments in pediatric health programs.