Prevalence and duration of PTSD in survivors 6 years after a natural disaster

•Long-term studies of PTSD after disasters are lacking.•We assessed PTSD in 142 disaster survivors with low levels of risk factors.•Post-disaster prevalence of PTSD was 11.3% and current prevalence was 4.2%.•Suicidal ideation and comorbidity was common among cases with PTSD.•Benign circumstances may affect prevalence but not the course or burden of PTSD.

The present study aimed to examine the prevalence of posttraumatic stress disorder (PTSD) in survivors with low levels of risk factors for PTSD. The sample included 142 adults (58% women, 54% university education, 93% employed/students/retired) on vacation in Southeast Asia during the 2004 Indian Ocean disaster. Semi-structured clinical interviews (SCID-I) were performed after 6 years including PTSD, depression, specific phobia, and alcohol abuse. The 6-year prevalence of PTSD was 11.3% and the current prevalence was 4.2%, with onset mainly within 1 month and remission within 3 years post-disaster. Suicidal ideation and comorbidity were common in PTSD cases. Lifetime prevalence of depression was 19%, specific phobia 7%, and alcohol abuse 4%. The findings suggest elevated levels of PTSD but not other disorders as compared with general population samples, but still lower levels than other disaster samples. Despite benign circumstances, however, the course and burden of PTSD were comparable to similar studies.