Abstract
<title>Abstract</title> <p>Background: Iodine deficiency disorder (IDD) is still a public-health problem in developing countries, and children in school are particularly vulnerable, since thyroid hormones play a key role in the neuro-cognitive development. Intake of iodine is determined by household knowledge and practice, but few studies have been done on the relation between these factors and children's cognitive outcomes in rural Khyber Pakhtunkhwa (KP), Pakistan. In this study, the degree of knowledge and practices of mothers on iodized salt and the relationship between maternal knowledge and practice with nutritional status and cognitive performance of school going children was assessed in Tehsil Katlang, KP. Methods: A cross sectional study, involving 300 mother–child pairs (aged 6-12 years) from 6 schools selected by stratified systematic random sampling was conducted in the community setting. Maternal knowledge and practice on iodized salt, dietary iodine intake, physical activity, sleep quality and screen-time were collected using structured questionnaires. Nutritional status was measured using height-for-age (HAZ) and BMI-for-age (BAZ) Z-scores, and cognitive performance was measured using Raven's Standard Progressive Matrices (SPM). Independent-samples t-tests, one-way ANOVA, chi-square tests and hierarchical multiple linear regression were used (at a significant level p<0.05). Results: Children's mean age was 8.41±2.04 years (50% male); 19.3% were stunted and 14.7% were thin. The majority of children (66.0%) had an average IQ, 22.7% above and 11.3% below average. The cognition was significantly associated with HAZ, BAZ, sleep quality and maternal knowledge of using iodized-salt, with higher scores for mothers of children with above-average-IQ (5.10±1.82) than for mothers of children with below-average-IQ (3.68±1.58). Age (β=0.386), HAZ (β=0.167), BAZ (β=0.109), sleep quality (β=0.121), maternal knowledge (β=0.173) and maternal practice (β=0.117) were independent positive predictors of IQ (all p<0.05) as revealed by hierarchical regression. Conclusions: Maternal knowledge and practices about iodised salt, the nutritional status of children and sleep quality are significantly related to cognitive performance in pre-adolescent children. The improvement of maternal nutrition education and salt-iodization in the households could have beneficial effects on developmental outcomes of children in rural Pakistan.</p>