Stimulant medications decrease energy expenditure and physical activity in children with attention-deficit/hyperactivity disorder.

Abstract

To determine the effect of stimulant medications used to treat children with attention-deficit/hyperactivity disorder (AD/HD) on energy expenditure, fuel utilization, and physical activity. Energy expenditure and physical activity were measured, respectively, by room respiration calorimetry and microwave motion detectors in 31 children with AD/HD (26 boys and 5 girls; ages 6 to 12 years) both while they were receiving their prescribed stimulant medication and after the medication had been discontinued for at least 24 hours. Fuel utilization was calculated from calorimetry data. Total and awake energy expenditure including energy expended while doing schoolwork, riding a stationary bicycle, resting, and watching a movie were from 4% to 8% lower when the children were receiving their prescribed stimulant medication. Total and awake activity were also lower while they were receiving medication (16% to 22%) and accounted for the lower rates of energy expenditure. Sleeping metabolic rate, basal metabolic rate, and fuel utilization were unaffected by medication. Stimulant medications decrease physical activity, and hence, decrease the activity component of total daily energy expenditure in children with AD/HD.