Changes of urine dihydroxyphenylglycol to norepinephrine ratio in children with attention-deficit hyperactivity disorder (ADHD) treated with atomoxetine

• Published in: Journal of child neurology Vol. 26; no. 1; p. 31
• Main Authors: Montoya, Alonso, Escobar, Rodrigo, García-Polavieja, María J, Lachno, D Richard, Alda, José Ángel, Artigas, Josep, Cardo, Esther, García, Marta, Gastaminza, Xavier, Gilaberte, Inmaculada
• Format: Journal Article
• Language: English
• Published: United States 01.01.2011
• Subjects: Adolescent; Adrenergic Uptake Inhibitors - therapeutic use; Atomoxetine Hydrochloride; Attention Deficit Disorder with Hyperactivity - drug therapy; Attention Deficit Disorder with Hyperactivity - urine; Child; Double-Blind Method; Female; Humans; Male; Methoxyhydroxyphenylglycol - analogs & derivatives; Methoxyhydroxyphenylglycol - urine; Norepinephrine - urine; Pilot Projects; Propylamines - therapeutic use; Treatment Outcome
• DOI: 10.1177/0883073810371981

This study investigated changes in the urine dihydroxyphenylglycol to norepinephrine ratio in patients with attention-deficit hyperactivity disorder (ADHD) treated with atomoxetine. The possible relationship with clinical response was also explored. Newly ADHD diagnosed, treatment-naïve children or adolescents were double-blindly randomized (2:1) to atomoxetine (n = 28) or placebo (n = 13). The dihydroxyphenylglycol to norepinephrine ratio decreased in both groups, showing significantly greater changes with atomoxetine than with placebo at week 6 (-42% versus -14%; P = .001), when dosed at 1.2 mg/kg/day, than at week 2 (-20% versus -2%; P = .118) with a dose of 0.5 mg/kg/day. Although the significant dihydroxyphenylglycol to norepinephrine ratio decrease with atomoxetine indicated norepinephrine transporter blockade, no association with ADHD clinical response (ADHD Rating Scale-IV-Parent:Investigator) was found. Therefore, dihydroxyphenylglycol to norepinephrine ratio might be a useful pharmacodynamic/pharmacokinetic biomarker, although not sufficiently sensitive to predict clinical efficacy. It remains a possibility that this ratio might have value to facilitate personalized atomoxetine pharmacotherapy in ADHD patients.