Iron Deficiency Parameters in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder

Abstract

The aim of this study is to compare iron deficiency parameters in patients with stimulant-naive attention-deficit/hyperactivity disorder (ADHD) and healthy controls, to investigate whether there are differences among the ADHD presentations, and to evaluate the relationship between ADHD symptom severity and serum ferritin levels. In addition, ADHD-Predominantly Inattentive (ADHD-PI) patients with restrictive hyperactivity/impulsivity symptoms were evaluated as a separate group with "restrictive inattention presentation" (ADHD-Rest) and were compared with other groups. Patients with ADHD-Rest are typically defined as having six or more symptoms of inattention and fewer than three symptoms of hyperactivity/impulsivity. A total of 200 ADHD cases consisting of 100 ADHD-Combine (ADHD-C) and 100 ADHD-PI and a total of 100 healthy control cases were included in the study. The Schedule for Affective Disorders and Schizophrenia for School Age Children-Present and Lifetime Version was performed in a semi-structured interview during the diagnosis. The Turgay DSM-IV-Based Child and Adolescent Behavior Disorders Screening and Rating Scale, the Conners' Rating Scale-Revised: Long Form (Parent-Teacher) (CPRSR:L, CTRS-R:L) were used for clinical evaluation. Hemogram, serum iron, iron binding capacity and serum ferritin levels were assessed. There were no significant differences between the ADHD patients and the healthy control cases in terms of iron deficiency parameters. Further, there were no significant differences among the ADHD presentations in terms of the same parameters, nor were there any significant differences when the groups were examined after the identification of the ADHD-Rest. The CPRS-R:L Hyperactivity and the CTRS-R:L Hyperactivity scores were negatively correlated with serum ferritin level in the ADHD group. To our knowledge, our current study is the first to compare serum ferritin levels in ADHD-Rest with other presentations of ADHD, and included the largest number of patients that were classified by ADHD presentations. Elucidation of these findings is important for both the etiology and treatment of ADHD.

Iron Status in Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analysis

“…The number of participants varied across studies, and ranged from 27 to 1260. Four studies were conducted in Europe [8, 13, 14, 18], one in the USA [11], one in Egypt [19], one in Brazil [20], and four in Asia [10, 21–23]. With the exception of three studies [8, 22, 23], all included studies reported medication use in the patients.…”

“…Similarly, Adisetiyo et al [11] found that medication-naïve patients with ADHD had lower estimated brain iron in the striatum and thalamus than did healthy controls. However, other authors have failed to find a relationship between serum ferritin and ADHD [12–14]. …”

Vitamin B12 and haemoglobin levels may be related with ADHD symptoms: a study in Turkish children with ADHD

“…Moreover, the results of the case control studies searching ferritin levels differ from each other. Donfrancesco et al [18], Menegassi et al [19] and Perçinel et al [17] did not find significant differences in ferritin levels between groups. On the contrary, some other studies detected lower ferritin levels in ADHD subjects [12,44,45].…”

“…We found a positive correlation between psychosomatic subscale of CPRS and ferritin. Other studies reported the relationship between the ADHD hyperactivity scores on Conners scale and low ferritin levels in their ADHD group [15][16][17]. Moreover, the results of the case control studies searching ferritin levels differ from each other.…”

“…On the other hand, the results of the studies investigating the role of iron deficiency and anaemia in ADHD are controversial [11]. Some studies have revealed that the severity of ADHD symptoms was related with low serum ferritin levels [12][13][14][15][16][17]. However, some other studies challenged these results and claimed that brain iron should be investigated in this kind of studies instead of serum ferritin levels [18,19].…”