Differences in vulnerability to traumatic stress among patients with psychiatric disorders: One-year follow-up study after the Great East Japan Earthquake

Abstract

Aims: The aim of this study was to evaluate differences in vulnerability to traumatic stress and the 1-year course of post-traumatic stress symptoms among patients with pre-existing psychiatric disorders after the Great East Japan Earthquake.

Methods: The Impact of Event Scale-Revised (IES-R) was used to assess post-traumatic stress symptoms in 612 patients with schizophrenic (ICD-10 F2; n = 163), mood (F3; n = 299), or neurotic disorders (F4; n = 150) at 1-4 months and again at 13-16 months after the disaster (retention rate: 68%).

Results: The mean IES-R total score for all diagnostic groups was 18.6 at index and 13.4 at follow up. The mean IES-R total score for patients with neurotic disorders (22.5) was significantly higher than that of patients with mood disorders (18.1) and schizophrenic disorders (15.9). At follow up, these scores decreased for all groups and inter-group differences were not observed.

Conclusions: Vulnerability to traumatic stress after a disaster was most severe in patients with neurotic disorders, followed by mood disorders, and, lastly, schizophrenic disorders. This difference among the three diagnostic groups was not found 1 year after the disaster.

Keywords: Great East Japan Earthquake; disaster; longitudinal study; post-traumatic stress disorders; psychiatric patient.