Impulsivity May Be Significant Factor in Childhood Aggression.
Impulsive aggression is a concept that cuts across diagnostic categories and may lead to research of the relationship between biologic and behavioral variables in youth violence, said Dr. Armenteros of the university.
Although aggression can take many forms--for defense, dominance, predation, or sexuality--impulsive aggression has more serious implications. It maybe evoked at significant personal and financial cost, often to the detriment of interpersonal relationships. And, it can lead to substantial work and school dysfunction, and even criminal, penalties.
In impulsive aggression, the impulsiveness, which is primary, triggers aggression. "The aggressive act per se is the observable manifestation of underlying impulsivity," Dr. Armenteros said.
Impulsive aggression is ubiquitous in psychiatry. It may appear in the context of attention-deficit hyperactivity disorder, personality disorders, conduct disorder, substance use disorders, manic episodes, and psychotic disorders and is a defining element of intermittent explosive disorder. "There is no diagnostic category for impulsive aggression, but we find it everywhere," he said at the meeting, which was also sponsored by the Florida Psychiatric Society.
Environmental factors, such as childhood exposure to aggression or parental dysfunction, may play a role in impulsive aggression. Accumulating biologic evidence suggests that the serotonergic neurotransmitter system is involved, probably reflecting genetic factors.
In a study of 36 impulsive and nonimpulsive male violent offenders, cerebrospinal fluid levels of a serotonin metabolite (cerebrospinal fluid 5-hydroxyindoleacetic acid [CSF 5-HIAA])) were significantly lower among the impulsive offenders.
Of the impulsive offenders, 20 were diagnosed with intermittent explosive disorder and 7 had antisocial personality disorder. Of the nonimpulsive offenders, nine had paranoid and passive aggressive personality disorder. No differences in CSF levels of other neurotransmitter metabolites were found between the groups, Dr. Armenteros said.
In another study comparing 29 children and adolescents with disruptive behavior disorders to 43 with obsessive-compulsive disorder, a relationship was found between lower concentrations of CSF 5-HIAA and disruptive behavior--particularly aggression, he said.
Some of the pharmacologic interventions that have been successful for managing impulsive aggression affect the serotonin system. For example, lithium indirectly increases serotonergic activity, and selective serotonin reuptake inhibitors increase it directly.
More systematic attention to impulsivity might improve treatment effectiveness and promote more fruitful research. "We've been using various drugs clinically without defining what population would benefit," Dr. Armenteros said.
|Printer friendly Cite/link Email Feedback|
|Publication:||Clinical Psychiatry News|
|Date:||Jul 1, 2001|
|Previous Article:||Soccer Heading Doesn't Impair Cognitive Function.|
|Next Article:||Children Often Are Direct Victims in Families Reported for Violence.|