Highly variable recurrence of tsunamis in the 7,400 years before the 2004 Indian Ocean tsunami.
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ABSTRACT:
SUBMITTER: Rubin CM
PROVIDER: S-EPMC5524937 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Despite significant research on the effects of stress on the hypothalamic-pituitary-adrenal (HPA) axis, questions remain regarding long-term impacts of large-scale stressors. Leveraging data on exposure to an unanticipated major natural disaster, the 2004 Indian Ocean tsunami, we provide causal evidence of its imprint on hair cortisol levels fourteen years later. Data are drawn from the Study of the Tsunami Aftermath and Recovery, a population-representative longitudinal study of tsunami survivors who were living along the coast of Aceh, Indonesia, when the tsunami hit. Annual rounds of data, collected before, the year after and 2 y after the disaster provide detailed information about tsunami exposures and self-reported symptoms of post-traumatic stress. Hair samples collected 14 y after the tsunami from a sample of adult participants provide measures of cortisol levels, integrated over several months. Hair cortisol concentrations are substantially and significantly lower among females who were living, at the time of the tsunami, in communities directly damaged by the tsunami, in comparison with similar females living in other, nearby communities. Differences among males are small and not significant. Cortisol concentrations are lowest among those females living in damaged communities who reported elevated post-traumatic stress symptoms persistently for two years after the tsunami, indicating that the negative effects of exposure were largest for them. Low cortisol is also associated with contemporaneous reports of poor self-rated general and psychosocial health. Taken together, the evidence points to dysregulation in the HPA axis and "burnout" among these females fourteen years after exposure to the disaster.
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Project description:Background: Posttraumatic growth (PTG) has been reported after various types of potentially traumatic events, as a part of the personal recovery process among survivors. Even negative changes in survivors' life view, known as posttraumatic depreciation (PTD), have been identified as an additional aspect in the personal recovery processes. Objective: To examine how the type of exposure experienced by survivors of a natural disaster, the 2004 Southeast Asia tsunami, influenced self-reported PTG and PTD six years later (T2). Additionally, the study examined the relations between psychological distress and posttraumatic stress symptoms (PTSS) 14 months after the disaster (T1), to PTG and PTD, respectively at T2. Finally, the study examined whether psychological distress and PTSS (T1) could have a mediating effect on PTG and PTD at T2. Method: The participants were 848 tsunami survivors living in Stockholm, Sweden who responded to a questionnaire at 14 months (T1) and six years (T2) after the tsunami. The material was analysed using linear regression and pathway analysis. PTG and PTD were measured on separate scales. Results: The type of exposure was significant related to both PTG and PTD six years later (T2). Those experiencing a combination of various types of exposure (including threat to life and bereavement) reported higher scores for both PTG and PTD. There were significant positive correlations between PTSS at T1 and PTG /PTD at T2, and somewhat lower correlations between psychological distress at T1 and PTG/PTD at T2. Both PTSS and psychological distress at T1 were significant mediating variables for both PTG and PTD at T2. Conclusions: Studying survivors' various types of exposure and subsequent changed view of life - both PTG and PTD - resulted in a broadened understanding of the complexity of reactions and the recovery process among survivors.
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