The coherence and correlates of intermittent explosive disorder amongst West Papuan refugees displaced to Papua New Guinea.

Questions remain about the nosological status of intermittent explosive disorder (IED) as a universal diagnosis. Cross-cultural studies are needed to establish whether IED symptoms form a coherent pattern and are distinguishable from other related symptom constellations. A study amongst a refugee population also allows further inquiry of the relationship between exposure to potentially traumatic events (PTEs) and other adversities with the IED constellation. In the present study amongst West Papuan refugees residing in Port Moresby, Papua New Guinea, we apply culturally adapted interview modules to assess symptoms of IED, post-traumatic stress disorder (PTSD), and depression, as well as the potentially traumatic events (PTEs) of conflict and ongoing adversity in the post-migration environment. Latent class analysis yielded a PTSD class (23%), a posttraumatic depressive class (14%), an IED class (12%), and a low/no symptom class (49%). Compared to the low/no-symptom class, the PTSD class had high levels of exposure to all PTE domains including childhood-related adversities, witnessing murder, human rights trauma, and traumatic losses, as well as ongoing adversity relating to displacement and separation from families, safety concerns, and lack of access to basic needs and health care. The posttraumatic depression class had greater exposure to traumatic losses and childhood-related adversities, higher levels of stress relating to material loss and deprivation, as well as to displacement and separation from families. In contrast, the IED class was distinguished only by the ongoing stress of displacement and separation from families in the homeland. Our findings provide support for the phenomenological distinctiveness of IED symptoms in this transcultural setting. Although not exclusive to IED, conditions of long-term displacement and separation appear to be a source of ongoing anger and explosive aggression amongst this population.