title: The postdisaster prevalence of major depression relative to PTSD in survivors of the 9/11 attacks on the World Trade Center selected from affected workplaces.
abstract: BACKGROUND
  Studies of survivors of the September 11, 2001 attacks on the World Trade Center in New York City suggest that postdisaster depressive disorders may be at least as prevalent, or even more prevalent, than posttraumatic stress disorder (PTSD), unlike findings from most other disaster studies. The relative prevalence and incidence of major depressive disorder (MDD) and PTSD were examined after the 9/11 attacks relative to trauma exposures.
  
  
  METHODS
  This study used full diagnostic assessment methods and careful categorization of exposure groups based on DSM-IV-TR criteria for PTSD to examine 373 employees of 9/11-affected New York City workplaces.
  
  
  RESULTS
  Postdisaster new MDD episode (26%) in the entire sample was significantly more prevalent (p<.001) than 9/11-related PTSD (14%). Limiting the comparison to participants with 9/11 trauma exposures, the prevalence of postdisaster new MDD episode and 9/11-related PTSD did not differ (p=.446). The only 9/11 trauma exposure group with a significant difference in relative prevalence of MDD and PTSD were those with a 9/11 trauma-exposed close associate, for whom postdisaster new MDD episode (45%) was more prevalent (p=.046) than 9/11-related PTSD (31%).
  
  
  CONCLUSIONS
  Because of the conditional definition of PTSD requiring trauma exposure that is not part of MDD criteria, prevalence comparisons of these two disorders must be limited to groups with qualifying trauma exposures to be meaningful. Findings from this study suggest distinct mechanisms underlying these two disorders that differentially relate to direct exposure to trauma vs. the magnitude of the disaster and personal connectedness to disaster and community-wide effects.
authors: Program in Trauma and Disaster and Staff Psychiatrist, VA North Texas Health Care System, Dallas, TX, USA; Departments of Psychiatry and Emergency Medicine, The University of Texas Southwestern Medical Center, 6363 Forest Park Rd., Dallas, TX 75390-8828, USA. Electronic address: carol.north@utsouthwestern.edu.
authors: Carol S
authors: CS
authors: North
authors: The University of Alabama at Birmingham, Department of Social Work, College of Arts and Sciences, Birmingham, AL, USA.
authors: David E
authors: DE
authors: Pollio
authors: Washington University School of Medicine, Department of Psychiatry, St. Louis, MO, USA.
authors: Barry A
authors: BA
authors: Hong
authors: Keck School of Medicine, Department of Psychiatry and Behavioral Sciences, University of California, Los Angeles, CA, USA.
authors: Anand
authors: A
authors: Pandya
authors: Ichan School of Medicine at Mt. Sinai and The New York Harbor Health Care System - Manhattan VA, New York, NY, USA.
authors: Rebecca P
authors: RP
authors: Smith
authors: The University of Oklahoma College of Medicine, Department of Psychiatry and Behavioral Sciences, College of Medicine, Oklahoma City, OK, USA.
authors: Betty
authors: B
authors: Pfefferbaum
mesh_terms: D000293:Adolescent; D000328:Adult; D003865:Major Depressive Disorder / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D015995:Prevalence; D047851:September 11 Terrorist Attacks / Q000523:psychology*; D013313:Stress Disorders, Post-Traumatic / Q000453:epidemiology* / Q000209:etiology; D017741:Survivors / Q000523:psychology / Q000706:statistics & numerical data*; D017132:Workplace / Q000523:psychology / Q000706:statistics & numerical data*