Prevalence and correlates of DSM-IV and DSM-5 Intermittent Explosive Disorder amongst Myanmar refugees living in Malaysia: a population-based study

AIMS: We investigate the prevalence and risk factor profiles of Intermittent Explosive Disorder (IED) and comparison between two diagnostic measures for IED in a large population-based study of three ethnic groups of refugees (Chin, Kachin and Rohingya) from Myanmar resettled in Malaysia. METHODS: Trained field personnel interviewed in total 2058 refugees, applying a clustered, probabilistic, proportional-to-size sampling framework and using the DSM-IV and DSM-5 criteria to diagnose IED. We used descriptive and bivariate analyses to explore associations of IED (using DSM IV or DMS 5) with ethnic group membership, sociodemographic characteristics and exposure to premigration traumatic events (TEs) and postmigration living difficulties (PMLDs). We also examined associations of IED with other common mental disorders (CMDs) (depression, anxiety and posttraumatic stress disorder) and with domains of functional impairment. Finally, we compared whether IED measured using DSM IV or DSM 5 generated the same or different prevalence. RESULTS: For the whole sample (n = 2058), the 12-month prevalence of DSM-IV IED was 5.9% (n = 122) and for DSM-5, 3.4% (n = 71). Across the three ethnic groups, 12-month DSM-5 IED prevalence was 2.1% (Chin), 2.9% (Rohingya) and 8.0% (Kachin), whereas DSM-IV defined IED prevalence was 3.2% (Chin), 7% (Rohingya) and 9.2% (Kachin). Being single, and exposure to greater premigration TEs and PMLDs were each associated with IED. Over 80% of persons with IED recorded one or more comorbid CMDs. Persons with IED also showed greater levels of functional impairment compared with those without IED. CONCLUSIONS: The pooled IED prevalence was higher than global norms but there was substantial variation in prevalence across the three study groups.