PLASMA-CORTISOL AND AGGRESSION IN BOYS WITH ADHD

Objective: The results of several studies suggest an inverse relations hip between cortisol secretion and aggressive behavior. This study exa mined basal plasma cortisol levels in aggressive and nonaggressive boy s with attention-deficit hyperactivity disorder (ADHD). Method: The su bjects were 23 aggressive and 27 nonaggressive boys with ADHD, aged 7 to 11 years. After 3 days of a low monoamine diet and an overnight fas t, an indwelling catheter was inserted into a forearm vein. Samples fo r plasma cortisol levels were obtained 105 and 115 minutes after inser tion of the catheter. Results: A one-way analysis of covariance (ANCOV A) controlling for body mass revealed no significant difference in pla sma cortisol between the aggressive and nonaggressive boys. Furthermor e, when the children were alternatively divided on the basis of the pr esence or absence of a DSM-III-R diagnosis of conduct disorder, a one- way ANCOVA again revealed no significant difference in cortisol levels . Conclusions: The hypothesized inverse relationship between cortisol secretion and aggressive behavior in boys with ADHD was not found. The se findings are consistent with a large body of literature indicating that the biological substrate of aggression is complex and that the id entification of biological laboratory markers of aggressive behavior i s not a clinically useful strategy at this time.