The psychological impact of terrorist attacks: examining a dose–response relationship between exposure to 9/11 and Axis I mental disorders

Background: Previous research has suggested a dose–response relationship between exposure to the 9/11 terrorist attacks and posttraumatic stress disorder (PTSD) and depression. However, this relationship has not been examined with other Axis I mental disorders. This study examined whether the incidence of Axis I mental disorders was associated with level of exposure to the 9/11 terrorist attacks. Method: Data came from the Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC‐2; N =34,653, ages 20+) collected between 2004 and 2005. This survey utilized a fully structured face‐to‐face interview to assess the presence of DSM‐IV Axis I disorders since Wave 1 of the NESARC, collected between 2001 and 2002. Multiple logistic regression analyses were employed to examine the relationship between the level of exposure to 9/11 and the prevalence of Axis I disorders since Wave 1. Results: In adjusted models, higher levels of exposure increased the odds of having new onset PTSD, any anxiety disorder, and any mental disorder. Compared to participants who were not exposed to 9/11, those who directly experienced 9/11 had six times the odds of having PTSD, 2.5 times the odds of having any anxiety disorder, and nearly twice the odds of having any mental disorder. Conclusions: Results suggest that there is a dose–response relationship between level of exposure to the 9/11 attacks and PTSD. Furthermore, higher levels of exposure increase the odds of having any anxiety disorder and any Axis I mental disorder. Depression and Anxiety, 2010. © 2010 Wiley‐Liss, Inc.