Characteristics of ADHD subtypes in Japanese children and the association with obesity based on BMI-SD score

In order to clarify the characteristics of attention deficit hyperactivity disorder (ADHD) subtypes in Japanese children and the association with obesity based on body mass index (BMI)-standard deviation (SD) score, we conducted a clinical survey of pediatric patients with ADHD.

We collected data for 115 patients diagnosed with ADHD. The patients were retrospectively divided into three groups according to subtype. Group 1 consisted of patients with predominantly inattentive ADHD (ADHD-I: n = 41, 35.7 %), Group 2 consisted of patients with predominantly hyperactive-impulsive ADHD (ADHD-HI: n = 6, 5.2 %), and Group 3 consisted of patients with a combined subtype (ADHD-C: n = 68, 59.1 %). The clinical features were analyzed for each group.

The most common ADHD subtype was ADHD-C, followed by ADHD-I and ADHD-HI. At the time of diagnosis and at the most recently follow-up, the ADHD-Rating Scale (RS) scores for total in Group 3 were higher than those in Group 1 or Group 2, and trouble score (TS) at the time of diagnosis and the frequency of patients requiring ADHD drugs medicine were higher in Group 3. Further, the BMI-SD scores in children with ADHD were high at 0.38 ± 1.1. The frequency of patients with a BMI-SD score above 2.0 was 7.3 % (n = 3) in Group 1, 16.7 % (n = 1) in Group 2, and 8.8 % (n = 6) in Group 3, and 8.7 % in all patients.

These results suggest that more careful follow-up is necessary for patients with ADHD-C than for those ADHD-I and ADHD-HI, and it is important to monitor the progress of ADHD children with obesity with the aim of improving their condition.