Prevalence and clinical correlates of intermittent explosive disorder in Turkish psychiatric outpatients

Intermittent explosive disorder (IED) is defined as the failure to resist aggressive impulses resulting in repeated acts of verbal and/or physical aggression. Although it is frequently encountered in clinical psychiatric practice, there is a paucity of data concerning IED in the scientific literature both internationally and in Turkey. The aim of this study was to evaluate the prevalence of IED and associated sociodemographic and clinical features in a clinical setting.

A total of 406 patients who were referred to our psychiatry outpatient clinic for the first time in a six-month period were included in the study. The diagnosis of IED was made using both Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV) and DSM-5 criteria. Axis I disorder and personality disorder diagnoses were made according to DSM-5 criteria. Diagnoses were based on information from the Structured Clinical Interview for DSM-IV (SCID I) and the Structured Clinical Interview for DSM-IV personality disorders (SCID II), Symptom Checklist-90 (SCL-90), Wender Utah Rating Scale, Adult Attention Deficit Hyperactivity Disorder (ADHD) DSM-IV Based Diagnostic Screening and Rating Scale, a clinical interview conducted by the researcher, and a sociodemographic data form. In addition, participants were administered the Buss-Perry Aggression Scale and Barratt Impulsiveness Scale Version 11 (BIS-11) to assess aggression and impulsivity.

Lifetime and 12-month prevalence of IED according to DSM-5 were 16.7% and 11.3%, respectively. Mean age at onset was 16.4 years. The prevalence of lifetime IED was 3.8 times higher in males than females (95% CI = 1.9-7.5); twice as high in individuals living in rural areas compared to those living in urban centers (95% CI = 1.1-3.7); 2.7 times higher among those with lifetime suicide attempt versus those without (95% CI = 1.3-5.6); 4.5 times higher in those with lifetime self-injurious behavior compared to those without (95% CI = 2.3-8.7); and 3 times higher in individuals reporting aggression/anger problems in the family compared to those without (95% CI = 1.5-5.9). The prevalences of childhood ADHD, conduct disorder, and oppositional defiant disorder were significantly higher in the IED group.

The result of the current study has revealed that approximately one-sixth of respondents experienced lifetime IED according to DSM-5 diagnostic criteria. Statistically significant sociodemographic correlates of IED include gender, urbanicity, history of suicide attempt, history of self-injurious behavior, and family history of aggression/anger problems.