Association of Hair Zinc Level with Cognitive and Language Delays in Children Aged 9–24 Months Old

Background: The delay in cognitive and language development can be caused by multifactor, including chronic deficiency of micronutrient, zinc. Level of zinc serum is influenced by food intake which can cause bias. There are inconsistencies in previous studies between zinc levels and the development caused by differences of sample or subjects. This study using hair as sample in analyzing the association between zinc level on cognitive and language delays in children aged 9-24 months old. AIM: To find out that low hair zinc level is associated with delayed of cognitive and language development in children 9-24 months old. Method: This analytical observational study with case-control design. Case group consisted of 69 children with cognitive and language development delays, based on CAT/CLAMS scores < 85 subjects aged 9-24 months meanwhile the control group consist of 69 children with normal cognitive and language development. Chi-square test was used to assess the association between zinc levels and the incidence of cognitive and language delays. Multivariate analysis was performed by logistic regression. Results: Univariate analysis showed no association between low zinc level and delayed of cognitive and language development in children aged 9-24 months (OR 1.263; 95% CI 0.64-2.46; p=0.495). Logistic regression was performed for other variables and screen time > 2 hours and lack of stimulation were risk factors for cognitive and language development delays (adjusted OR 2.78; 95% CI 1,284-6.058; p=0.010 and adjusted OR 3.96; 95% CI 1.833-8.581; p<0.001). Conclusion: There is no relationship between low hair zinc level and delays in cognitive and language development in children age 9-24 months, but there is an association between screen time more than two hours per day and lack of stimulation with delays in cognitive and language development in children 9-24 months 24 months.