Aggression Tied to Serotonergic, Structural Deficits: Intermittent Explosive Disorder. (Adult Psychiatry)
MacReady, Norra, Clinical Psychiatry News
SANTA FE, N.M. -- A growing body of research suggests that intermittent explosive disorder, characterized by regular impulsive, aggressive acts, is the result of childhood abuse combined with biological predisposition, Dr. Emil F. Coccaro said at a clinical psychiatry symposium sponsored by the University of Arizona.
He cited the Dunedin (New Zealand) Multidisciplinary Health and Development Study, which examined the effects of maltreatment in 26-year-old New Zealand men with a polymorphism of the gene that codes for the synthesis of monoamine oxidase A (MAOA).
Of 163 men with low MAOA activity, about 28% of those who had experienced probable maltreatment and about 32% of those who had experienced severe maltreatment between the ages of 10 and 18 had been convicted of a violent offense by the time they were 26 years old. Those percentages were significantly higher than those seen in the 279 men with high MAOA activity, even if they'd been exposed to severe maltreatment as boys (Science 297 :851-854, 2002).
Recently, researchers in the Dunedin study reported finding a link between the 5-HT T gene, depression, and stressful events (CLINICAL PSYCHIATRY NEWS, August 2003, p. 8).
For his part, Dr. Coccaro and his colleagues found a correlation coefficient of 0.77 between high scores on the Buss-Durkee Hostility Inventory and a blunted prolactin response to a challenge with 60 mg fenfluramine, which is a measure of central serotonergic function. They studied 45 men with major affective disorder (n=25) or personality disorder (n=20), and their results suggested that serotonergic function was low in both groups of patients, compared with a healthy control group.
In another study, Dr. Coccaro and his colleagues examined the relationship between aggression and levels of arginine vasopressin (AVP), which has been shown in animal studies to facilitate aggressive behavior. They found a statistically significant correlation coefficient of 0.41 between a life history of general aggression and the level of AVP in the cerebrospinal fluid of 18 men and 8 women who had a variety of Axis I and Axis II personality disorders, including intermittent explosive disorder (lED) in 3 patients, and a lifetime history of generalized aggression. …