Zinc deficiency in children with attention-deficit hyperactivity disorder

Abstract

Background Attention-deficit hyperactivity disorder (ADHD) is a common behavioral disorder in children that may persist into adulthood. Insufficient nutritional supply and deficiency of trace elements and other components including various minerals have been suggested to play a role in the development of ADHD symptoms. Zinc in particular was found to be significantly deficient in patients with ADHD compared with healthy controls, so it was concluded that zinc deficiency might play a role in the etiopathogenesis of ADHD. Objectives The aim of the work is to investigate the association of serum zinc levels with ADHD diagnosis, its symptom domains, and severity. Patients and methods A total of 75 children aged from 6 to 14 years with Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) diagnosis of ADHD were enrolled in this study. All children were assessed using Colored Progressive Matrices IQ test, Kiddie Schedule for Affective Disorders and Schizophrenia for School Age Children Present and Lifetime version (K-SADS-PL), the Working Memory Index (WMI) of Wechsler Intelligence Scale for Children (WISC-III), and Conner’s Parent Rating Scale − Revised − Long version (CPRS-R-L). Serum zinc level was measured in all children using atomic absorption spectroscopy. Results Overall, 52% of children with ADHD (n=39) had forthright zinc deficiency with serum zinc levels less than 60 μg/dl. Five children only had marginal zinc levels, with serum zinc level ranging between 60 and 80 μg/dl. Serum zinc levels were lower in children living in rural areas. Zinc-deficient children showed lower IQ scores than non-zinc-deficient group.