Serotonergic functioning and trait-impulsivity in attention-deficit/hyperactivity-disordered boys (ADHD): influence of rapid tryptophan depletion.
OBJECTIVE
The present study investigated the effects of rapid tryptophan depletion (RTD) and the ensuing reduction of central nervous levels of serotonin (5-HT) on reactive aggression with respect to personality factors comprising aspects of trait-impulsivity and -aggression in boys with attention-deficit/hyperactivity-disorder (ADHD).


METHODS
Twenty-two male adolescent patients with ADHD received the RTD test on one day, and, on another day a tryptophan balanced placebo in a double-blind within-subject crossover design. Impulsive personality factors and trait-impulsivity were assessed in advance of the study. Aggression was provoked using a competitive reaction time game 270 min after RTD/placebo intake.


RESULTS
RTD had a significant effect on increased aggressive behaviour with which low-grade impulsive patients responded. High-grade impulsive patients were not affected by RTD or even responded with increased aggressive behaviour while receiving placebo treatment.


CONCLUSIONS
The present study supports the hypothesis that 5-HT functioning in ADHD patients influences reactive aggression depending on aspects of trait-impulsivity. Future studies are necessary in order to detect the specific influence of ADHD as regards the relevance to 5-HT-induced changed aggressive responding.
Zepf
Florian Daniel
FD
Department of Child and Adolescent Psychiatry and Psychotherapy, J.W. Goethe University of Frankfurt a.M., Germany. F.Zepf@med.uni-frankfurt.de
Stadler
Christina
C
Demisch
Lothar
L
Schmitt
Marcus
M
Landgraf
Meike
M
Poustka
Fritz
F
D000374:Aggression; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications; D002648:Child; D018592:Cross-Over Studies; D004038:Diet, Reducing / Q000009:adverse effects*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D006801:Humans; D007175:Impulsive Behavior / Q000209:etiology / Q000378:metabolism*; D008297:Male; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000502:physiology; D012701:Serotonin / Q000378:metabolism*; D014364:Tryptophan / Q000172:deficiency*
D012701:Serotonin; D014364:Tryptophan