Chapter 28. Impulse-Control Disorders

Although impulse-control disorders are often thought to be rare conditions, a recent replication of the National Comorbidity Study demonstrated a 12-month prevalence rate of 8.9%. This percentage however also included disorders such as oppositional defiant disorder (1%), conduct disorder (1%), and attention-deficit/hyperactivity disorder (ADHD) (4.1%). Intermittent explosive disorder was reported at 2.6% of the surveyed population. Intermittent explosive disorder and pathological gambling (0.2–3.3% of populations surveyed) are much more common than the other disorders in this group.

Essentials of Diagnosis

DSM-IV-TR Diagnostic Criteria

1. Several discrete episodes of failure to resist aggressive impulses that result in serious assaultive acts or destruction of property.

2. The degree of aggressiveness expressed during the episodes is grossly out of proportion to any precipitating psychosocial stressors.

3. The aggressive episodes are not better accounted for by another mental disorder (e.g., antisocial personality disorder, borderline personality disorder, a psychotic disorder, a manic episode, conduct disorder, or ADHD) and are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition (e.g., head trauma, Alzheimer's disease).

(Reprinted, with permission, from Diagnostic and Statistical Manual of Mental Disorders, 4th edn. Text Revision. Washington DC: American Psychiatric Association, 2000.)

General Considerations

Epidemiology

The National Comorbidity Study replication reported a 12-month prevalence rate of 2.6%. This is more common than previously realized.

Etiology

The outbursts associated with intermittent explosive disorder (sometimes referred to as episodic dyscontrol) were initially viewed as the result of limbic system discharge or dysfunction or even as interictal phenomena. The Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) does now exclude those patients in whom an aggressive episode was thought to be related to a general medical condition (e.g., temporal lobe seizures, delirium) or to the direct psychological effects of a substance, whether a drug of abuse or a prescribed medication. Disorders that can be identified as resulting from neurological insult or a seizure disorder are now classified elsewhere. Nevertheless, neurological soft signs, nonspecific electroencephalogram anomalies, or mild abnormalities on neuropsychological testing have been noted in patients given this diagnosis.

Psychodynamic explanations have also been proposed. Childhood abuse is thought to be a risk factor for the development of this disorder. Others postulate narcissistic vulnerability as a possible mechanism that triggers these attacks. Thus, one can conceptualize the “explosive” episodes as resulting from a real or perceived insult to one's self-esteem or as a reaction to a perceived threat of rejection, abandonment, or attack.

Genetics

Little is known about the genetics of intermittent explosive disorder. Family studies of ...