TABLE 1

General Characteristics of and Blood Micronutrient Levels in Subjects With ADHD and Control Subjects

ADHD Cases (n = 60)Controls (n = 60)P
Sex, % male (n)56.7 (34)56.7 (34)
Age, y9.3 (2.8)9.3 (2.8)
Height, cm136.5 (16.8)138.6 (17.3).496
Weight, kg38.1 (16.2)36.4 (14.5).536
BMI19.6 (4.3)18 (3.3).042*
BMI z score0.69 (1.1)0.25 (1.1).027*
Body weight at birth, %
 <2.5 kg13.35.0.114
 >2.5 kg86.795.0
Physical activity,a kcal/d1248.3 (824.6)861.4 (483.3).013*
Maternal smoking pregnancy, %22.08.3.037*
Breastfeeding, %66.783.3.035*
Breastfeeding length,b mo5.8 (5.7)5.7 (5.9).931
Maternal educational level,c %63.388.3<.001*
Paternal educational level,c %55.076.7.012*
Biological father living with family, %81.796.7.008*
Marital status of parents,d %18.35.0.023*
Nutrient plasma levels
 Iron, μg/dL80.1 (32.5)85.4 (32.1).366
 Transferrin, mg/dL266.2 (29.9)265.7 (27.9).922
 Ferritin, μg/L36.2 (21.0)42.2 (36.9).273
 Zinc, μg/L988.6 (182.0)975.5 (162.0).680
  • Data are presented as means (SDs) unless otherwise indicated. —, not applicable.

  • a Measured with the actigraphy accelerometer ActiSleep.

  • b Calculated for those who breastfed.

  • c More than primary school.

  • d Separated/divorced.

  • * P < .05.