ESSENTIAL TRACE ELEMENTS: POSSIBLE ROLE IN THE ETIOPATHOGENESIS OF AUTISM SPECTRUM DISORDER AND SPEECH DEVELOPMENT DELAY IN CHILDREN OF DIFFERENT AGES

An imbalance of trace elements plays a significant role in the etiopathogenesis of Autism Spec-trum Disorder (ASD) and Speech Development Delay (SDD). The aim of the study was to analyze an essential trace elements content in the hair samples of children with ASD and SDD for better understanding age and gender related diversity. The study included 258 children with ASD and 239 children with SDD. Control group consisted of 620 healthy children of similar age. All children were divided into two age categories (1.5 to 3 years old and 4 to 13 years old). It was shown that girls with ASD had more deviations in hair essential trace elements levels than boys. Children with ASD and SDD (1.5 to 3 years old) had significantly decreased hair iodine level (by 48-58%, p < 0.0001). Low iodine level can be a significant indicator of mental and speech development delay. Normalization of hair iodine level in older boys with ASD accompanied by significant decrease in hair cobalt level (by 24%, p = 0.0001) may reflect age-related characteristics of iodine and cobalt metabolism. Low hair manganese level (by 12-44%, p < 0.05) was observed in all groups of children. It’s possibly associated with decreased manganese excretion from the body and can provoke manganese-induced neurotoxicity. The decrease in copper levels in girls of different ages (by 9-17%, p < 0.01) is probably influenced by hormonal status and earlier onset of puberty.