Sleep, symptom-ratings and serum ferritin levels in children with ADHD

Abstract

The present study was conducted to describe sleep problems in a sample of Egyptian children with ADHD and to examine the effect of low serum ferritin levels on their sleep and symptom-ratings. The parents of 41 ADHD children, aged 6–12 years, filled out the Children’s Sleep Habits Questionnaire (CSHQ) and Conners’ Parent Rating Scale-Revised: long version (CPRS-R:L) in Arabic. Serum ferritin levels of the children were determined with the enzyme-linked immunosorbent assay method. The parents of 62 normal control children filled out the CSHQ. The ADHD group had significantly higher scores on bedtime resistance, sleep anxiety, parasomnias, sleep-disordered breathing, daytime sleepiness and global sleep disturbance (CSHQ total score) than in the control group. Children with serum ferritin levels <30 ng/mL had more disturbed sleep than children with serum ferritin levels ⩾30 ng/mL. There were significant negative correlations between sleep duration subscale, total score of CSHQ, and serum ferritin levels (p<0.05). There were no significant differences in ADHD symptoms in regard to ferritin levels (p > 0.05). Sleep problems are common among this sample of children with ADHD. This study suggests an association between low serum ferritin levels and sleep disturbances among Egyptian children with ADHD. We would like to thank the parents and the children for participation in this study. Also, we would like to thank Janssen-Cilag pharmaceutical company that paid the cost of the CPRS-R:L questionnaire.