57 Response to Iron Supplementation in Children with Autism Spectrum Disorder

Our main objective was to determine the change in serum ferritin level in response to iron supplementation in children with Autism Spectrum Disorder (ASD) seen at a tertiary level center. Our secondary objective was to document the relationship between low ferritin and low dietary iron. An open-label treatment trial was conducted with children who had previously demonstrated low serum ferritin measured during clinical diagnostic evaluations for ASD between 1998 and 2003. Diagnostic measures included the Autism Diagnostic Interview-Revised (ADI-R), Autism Diagnostic Observation Schedule (ADOS), and clinical evaluation. All children were prescribed 8 weeks of oral iron suspension or sprinkles. Dietary intake, compliance and side effects were tracked using a 3-day Food Record Form and a Nutritional Supplement Log. Serum ferritin and blood indices, including mean corpuscular volume (MCV) and hemoglobin (Hb) were measured at baseline and after 8 weeks of treatment. Thirty-three children completed the study (mean age 6 years 3 months, 35 males, 8 females); 85% had ferritin <22 μg/L and 30% had ferritin <12 μg/L. There were significantly more preschoolers with ferritin <12 μg/L (Chi2=6.9, p=.018), but there were no gender differences. Fifty-two percent of the sample had insufficient dietary iron intake; over half of these were preschoolers. Dietary sufficiency was not correlated with serum ferritin levels. Mean ferritin level increased significantly from 16 μg/L to 29 μg/L with a mean of 7 weeks of treatment (T=–5.02, p<.000). Ferritin level in 6 out of 8 preschoolers remained <12 μg/L despite treatment. At baseline, MCV was low in 42%, and Hb was below expected range for age in 9%. Mean MCV levels improved significantly with the treatment (T=–3.38, p=.002). No association was found between low ferritin and autistic symptomatology based on ADI-R or ADOS scores.

Low serum ferritin is common in children with ASD. Signs of iron-deficient erythropoeisis were common, representing a more advanced stage of iron deficiency. Although mean ferritin levels increased overall with iron supplementation, the iron stores of a minority of children (all preschoolers) remained depleted following treatment. MCV improvement suggests some benefit from the treatment; this subset may require prolonged treatment to replete iron stores. These findings emphasize the importance of recognizing and treating iron deficiency in children with ASD.