Differences associated with different prior mental disorders among earthquake-exposed treatment-seeking individuals.

Background: History of prior mental disorder, particularly post-traumatic stress disorder (PTSD), increases risk for PTSD following subsequent trauma exposure. However, limited research has examined differences associated with specific prior mental disorders among people with PTSD.

Aims: The current study examined whether different prior mental disorders were associated with meaningful differences among individuals presenting to a specialist service for severe earthquake-related distress following the Canterbury earthquakes (N = 177).

Method: Two sets of comparisons were made: between participants with no history of prior disorder and participants with history of any prior disorder; and between participants with history of prior PTSD and those with history of other prior disorders. Comparisons were made in relation to sociodemographic factors, earthquake exposure, peri-traumatic distress, life events and current psychological functioning.

Results: Participants with any prior mental disorder had more current disorders than those with no prior disorder. Among participants with history of any prior disorder, those with prior PTSD reported more life events in the past 5 years than those with other prior disorders.

Conclusions: Findings suggest a history of any prior mental disorder contributes to increased clinical complexity, but not increased PTSD severity, among people with PTSD seeking treatment. Although post-disaster screening efforts should include those with prior mental disorders, it should also be recognised that those with no prior disorders are also at risk of developing equally severe PTSD.