Intermittent Explosive Disorder (IED)

Defining intermittent explosive disorder

Intermittent explosive disorder is psychiatric condition in which there are "discrete episodes of failure to resist aggressive impulses resulting in serious assaults or destruction of property" (Diagnostic and Statistical Manual, 4th Edition, (DSM-IV) produced and published by the American Psychiatric Association).

The DSM-IV criteria for making a diagnosis of intermittent explosive disorder includes the condition that the magnitude of the aggressive outbursts is out of proportion to whatever triggered it.

The DSM-IV also stipulates that in order to make a diagnosis of intermittent explosive disorder, all other psychiatric disorders that might account for the aggression has been ruled out. These include manic episode, conduct disorder, anti-social personality disorder, borderline personality disorder, or attention deficit hyperactivity disorder.

Common characteristics of intermittent explosive disorder

Individuals with intermittent explosive disorder may show signs of generalized impulsivity or aggressiveness between the episodes of explosive aggression. They are likely to experience problems at school, at work, and in interpersonal relationships.

Serious cases of aggression can result in hospitalization due to retaliation by the victim, or legal actions and possible incarceration.

The onset of intermittent explosive disorder usually occurs in early adolescence with a mean onset age of just 14 years (Kessler et al, 2006).

There was little correlation between socio-demographic variables such as socioeconomic status and the occurrence of intermittent explosive disorder. It was also found that intermittent explosive disorder was significantly comorbid with “most DSM-IV mood, anxiety, and substance disorders” (Kessler et al, 2006).

Explosive episodes has similarities to manic periods: the high rate of lifetime comorbid of bipolar disorder and intermittent explosive disorder, and the usefulness of mood-stabilizing drugs to control explosive episodes.

Because of the similarities, it has been suggested that intermittent explosive disorder may be linked to bipolar disorder in some way e.g. a similar underlying biochemical mechanism (McElroy, 1999).

Lifetime prevalence

The most recent estimate of the lifetime prevalence of intermittent explosive disorder was found to be 7.3% (Kessler et al, 2006).

However a previous study (Kessler 2005) which compared all of the impulse control disorders found a lifetime prevalence of just 5.2%. In this study it was the least prevalent of the impulse control disorders outranked in decreasing order of lifetime prevalence by conduct disorder at 9.5%, oppositional defiant disorder at 8.5%, and attention deficit hyperactivity disorder at 8.1%.

The DSM-IV, published in 1994, states that intermittent explosive disorder is "apparently rare".

However, the lifetime prevalence of 7.3% obtained in the most recent research (Kessler et al,2005) is comparable to the lifetime prevalence found for posttraumatic stress disorder and drug abuse and so can hardly be considered rare.

This discrepancy may be due to an increase in prevalence over time or to differences in assessment procedures. In the conclusion of the 2006 study by Kessler and his colleagues, it is stated "Intermittent explosive disorder is a much more common condition than previously recognized”.

Treatments Suggested

The treatment of intermittent explosive disorder has received relatively little attention by mental health researchers as evidenced by the paucity of publications on this topic in the professional journals. Only four approaches could be found:

  • Pharmacological. Although there is a deficit in properly controlled research studies on the effectiveness of medications for intermittent explosive disorder, there is evidence that “mood stabilizers, antipsychotics, β-blockers, α2-agonists, phenytoin and antidepressants may be useful” (Olvera, 2002).
  • Behavioral interventions may be valuable as part of the overall treatment of intermittent explosive disorder (Olvera, 2002).
  • Group Cognitive Behavioral Therapy (McCloskey, Noblett, & Gollan, 2004).
  • Combined treatments. In a recent review of the treatment of intermittent explosive therapy, the authors, Coccaro and McCloskey (2006), discuss a variety of treatment approaches including medication and cognitive behavioural therapy.

References

American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders. (4th ed.) Washington, DC: Author.

Coccaro, E. F., & McCloskey, M. S. (2006). Hothead Harry, gnome assassin: Combined treatment of intermittent explosive disorder. In R. L. Spitzer, M. B. First, J. B. W. Williams, & M. Gibbon (Eds.), DSM-IV-TR® casebook: Experts tell how they treated their own patients ( Vol. 2, pp. 364-375). Arlington, VA: American Psychiatric Publishing.

Kessler, R. C., Berglund, P., Demler, O., Jin, R., Merikangas, K. R., Walters, E. E., (2005). Lifetime Prevalence and Age-of-Onset Distributions of DSM-IV Disorders in the National Comorbidity Survey Replication. Archives of General Psychiatry, Vol. 62(6), 593-602.

Kessler, R. C., Coccaro, E. F., Fava, M., Jaeger, S., Jin, R., & Walters, E. (2006). The Prevalence and Correlates of DSM-IV Intermittent Explosive Disorder in the National Comorbidity Survey Replication. Archives of General Psychiatry, 63(6), 669-678.

Olvera, R.L. (2002). Intermittent explosive disorder: Epidemiology, diagnosis and management. CNS Drugs, 16(8), 517-526.

McElroy, S. L. (1999). Recognition and treatment of DSM-IV intermittent explosive disorder . Journal of Clinical Psychiatry, Vol. 60(Suppl 15), 12-16.

McCloskey , M. S. Noblett , K. L. Gollan , J. K. (2004). The Efficacy of Group Cognitive Behavioral Therapy in Reducing Anger Among Patients with Intermittent Explosive Disorder: A Pilot Study. Poster presented at the 2004 annual meeting of the Association for the Advancement of Behavior Therapy, New Orleans, LA.