Effect of 25 hydroxyvitamin D on attention deficit and hyperactivity in school-age children with ADHD

To observe the serum levels of 25 hydroxyvitamin D [25 (OH) D] in healthy school-age children and children with attention deficit hyperactivity disorder (ADHD) and to analyze the effects of serum 25 (OH) D on the symptoms of attention deficit and hyperactivity in school-age children with ADHD.

According to the Diagnostic and Statistical Manual of Mental Disorders DSM-IV diagnostic criteria for ADHD in children, 80 healthy children aged 6 years or less than 10 years old and children diagnosed with ADHD in the Department of Rehabilitation Medicine, Department of Pediatrics and Department of Physical Examination of our hospital were randomly selected as research subjects. The serum 25 (OH) D level, attention deficit hyperactivity (Swanson, Nolan, and Pelham, version IV [SNAP-IV] parental version) score and Conners child behavior (PSQ) index were observed and compared between the 2 groups. In addition, the children with ADHD whose serum 25 (OH) D was lower than normal were treated with supplemental VitD3, and the changes in serum 25 (OH) D, SNAP-IV parental score and PSQ index of ADHD children were observed and compared.

Serum 25(OH)D was insufficient or deficient in 26 healthy children, but the SNAP-IV score and PSQ index were normal. Serum 25(OH)D was lower than normal in 69 patients in the ADHD group, which was negatively correlated with SNAP-IV score (r = -0.3479, P = .0034) and negatively correlated with PSQ index (r = -0.3566, P = .0026). After vitamin D3 (VitD3) supplementation in 69 children with serum 25(OH)D levels lower than the normal ADHD group, it was found that the SNAP-IV score (r = -0.4654, P = .0037) and PSQ index (r = -0.5680, P = .0002) of 34 children with ADHD were negatively correlated with the increase in serum 25(OH)D. The SNAP-IV score and PSQ index of the other 35 children with ADHD showed no correlation with the increase in serum 25 (OH) D (P > .05).

Serum 25(OH)D levels lower than normal are more common in school-age children, and levels lower than normal are not the key pathogenic factor of ADHD in school-age children, but serum 25(OH)D levels lower than normal may be the upregulation factor of attention deficit and hyperactivity disorder expression in some school-age children with ADHD. The lower level of serum 25(OH)D may be closely related to the severity of ADHD symptoms in some children.