162 Intermittent Explosive Disorder (312.34)

Intermittent explosive disorder, also known as IED, is characterized by the failure to resist aggressive impulses, which result in serious assaults or property destruction (American Psychological Association, 2000). The degree of aggression displayed during these outbursts is grossly out of proportion with the events that provoke them. (Bayer, 2000). The short-lived episodes of aggression provide a way for the person with IED to vent his or her anger and frustration (Bayer, 2000). These verbal or physical outbursts are much more intense than normal anger, and the individual with IED is unable to control them (Bayer, 2000). The aggression the individual feels is often ego-dystonic, so they may feel regret or guilt after committing the aggressive act (Bayer, 2000; Blankenship, 2008). IED is not the same as aggression that is purposeful and premeditated, and it does not arise out of personal motives, such as revenge, social dominance, or monetary gain (Blankenship, 2008).

History of IED:

• The name of this disorder has changed over time and so has the diagnostic criteria listed in the DSM. In the DSM-I, IED was called passive aggressive personality, aggressive type; in the DSM-II, it was renamed explosive personality disorder.
• The term intermittent explosive disorder was first used in the DSM-III, and the diagnostic criteria excluded individuals with antisocial personality disorder and generalized aggression or impulsivity (Blankenship, 2008).
• In the DSM-III-R, individuals with borderline personality disorder were also excluded (Blankenship, 2008).
• The current diagnostic criteria for IED no longer excludes generalized aggression or impulsivity (Blankenship, 2008).
• For an individual to be diagnosed with IED, the outbursts cannot be triggered by other disorders or medication. However, people with IED very likely to abuse drugs (Bayer, 2000).

IED and suicide:

• A study assessing the prevalence rates of suicidal and self-injurous behavior among individuals with IED found that approximately 17% of patients exhibited self-aggressive behavior, 12.5% had attempted suicide, and 7.4% had performed non-suicidal, self-injurous behavior (McCloskey, Ben-Zeev, Lee & Coccaro, 2008).
• It was also found that women were at an increased risk for self-injurous behavior overall (McCloskey et al., 2008).
• Furthermore, individuals with major depressive disorder were found to be at a higher risk of self-aggressive behaviors, including suicide attempts (McCloskey et al., 2008).

DSM-IV-TR criteria

• A. Several discrete episodes of failure to resist aggressive impulses that result in serious assaultive acts or destruction of property.
• B. The degree of aggressiveness expressed during the episodes is grossly out of proportion to any precipitating psychosocial stressors.
• C. 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 Attention-Deficit/Hyperactivity Disorder) 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)

Associated features

Some individuals see their impulses as stressful and destructive before, during, and after they react to these impulses. Episodes may be associated with affective symptoms (racing thoughts, rage, etc.) during the aggressive acts and rapid onset of depressed mood after the acts. Some episodes may be preceded by tingling, tremors, palpitations, chest tightness, hearing an echo, or head pressure (Bayer, 2008). These reactions can cause problems socially in their relationships, school, and/or jobs. Individuals with IED can sometimes suppress their anger, to an extent, and react in a less destructive manner. Signs of impulsivity or aggressiveness may be present between episodes (Bayer, 2008). They may report problems with anger and “sub-threshold” episodes. Individuals with narcissistic, obsessive, paranoid, or schizoid traits may be especially prone to having explosive outbursts of anger when under increased stress.

Child vs. adult presentation

Children may react with a temper, hyperactivity, or destructive actions such as tearing up objects, setting objects on fire, or taking from others. There is no exact age of when IED begins, however it is believed to occur from childhood to late teens or twenties.

Gender and cultural differences in presentation

This episodic violent behavior is more frequent in men than women (Bayer, 2008). One form of aggression, known as amok, is characterized by acute, unrestrained violence, typically associated with amnesia. This is primarily seen southeastern Asia but has also been seen in Canada and the United States. Unlike IED, Amok does not occur frequently but in a single episode.

Epidemiology

• Very little is known about the epidemiology of intermittent explosive disorder.
• Studies have found that IED may be present in over 5% of the population (Kessler, Coccaro, Fava, Jaeger, Jin & Walters, 2006).
• One study found that from 3.4% to 10.4% of patients in a psychiatric facility had IED characteristics at some point in their lives (Grant, Levine, Kim & Potenza, 2005).
• There is limited data on age at onset, but it appears to be between childhood and the early twenties (Bayer, 2008). The onset may be abrupt with no prodromal period, and the course varies (Bayer, 2008). The course is chronic in some individuals and episodic in others (Bayer, 2008).

Etiology

Developmental problems or neurological symptoms maybe a cause. There may be an imbalance of serotonin or testosterone levels. However, if a physician believes it is due to physiological problems, it may be diagnosed as a general medical condition instead. It may also be caused at a young age due to exposure in family situations where explosive behavior, verbal, or physical abuse were frequent. Exposure to violence at an early age makes it more probable for them to show the same traits as they mature. A genetic factor may also be the cause, allowing the disorder to be passed down.

Empirically supported treatments

Few controlled studies involving treatments for IED exist. Some patients respond to treatments with certain medications such as anti-convulsion, anti-anxiety, mood regulators, anti-depressants, antipsychotics, beta-blockers, alpha(2)-agonists, or phenytoin. Also, some forms of group therapy, such as anger management, may be helpful. Treatment can include also cognitive behavioral therapy that helps the person identify triggers for outbursts and avoid them.