Probable posttraumatic stress disorder among New York City firefighters exposed to the terrorist attacks on the World Trade Center towers continues to be associated with early arrival to the site, even 9 years after the disaster.
Other factors associated with persistence or onset of PTSD symptoms were subsequent decreases in exercise, increases in alcohol intake, and concurrent symptoms of respiratory or gastroesophageal illness.
Michael Rieger/FEMA News Photo
Although the 9/11 disaster was roughly a decade ago, numerous NYC firefighters may still be suffering from posttraumatic stress disorder.
The findings come from the longest follow-up to date of probable PTSD after the World Trade Center (WTC) attacks on Sept. 11, 2001, among New York City firefighters who were part of the rescue/recovery effort.
"Previous studies tracking the trajectory of PTSD after and event have ended within 6 years of follow-up," researchers led by Jackie Soo of the department of medicine at Montefiore Medical Center, New York, noted in the study, which was published online Sept. 7 (Disaster Med. Public Health Prep. 2011 [doi:10.1001/dmp.2011.48]). "Our work shows that the association between experiencing trauma and PTSD may persist well beyond that time frame."
Ms. Soo and her associates examined data from 11,006 uniformed New York City firefighters who completed 40,672 questionnaires during the 9 years after 9/11. Respondents were categorized into four groups: those who arrived during the morning of Sept. 11 (arrival group 1), those who arrived during the afternoon of Sept. 11 (arrival group 2), those who arrived on day 2 (arrival group 3), and those who arrived between days 3-14 (arrival group 4).
In years 1-4, the researchers evaluated PTSD with a modified version of the PTSD CheckList – Civilian Version (PCL), a 14-item self-reported survey that corresponds to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Respondents answered on a binary scale. In years 6-9, PTSD was evaluated with the original version of the PCL-C, which contains 17 items and which respondents answered on Likert scale.
The respondents also were asked about their change in alcohol intake since Sept. 11, change in exercise (since the individual’s last questionnaire), smoking status (at the time of the questionnaire), as well as the presence of wheeze, shortness of breath, or other aerodigestive symptoms.
Ms. Soo and her associates reported that 7.4% of the respondents met criteria for probable PTSD. By comparison, the National Comorbidity Survey Replication, administered from 2001-2003, estimated the prevalence of PTSD in the United States population to be 1.8%. Firefighters in arrival group 1 had the highest prevalence in all years, ending at 13.4% in year 9.
Longitudinal analyses revealed that a lower likelihood of recovery from probable PTSD was associated with an increasing number of aerodigestive symptoms (hazard ratio, 0.89/symptom) and reporting a decrease in exercise, whether the result of health (HR, 0.56 vs. no change in exercise) or other reasons (0.76 vs. no change in exercise).
Delayed onset of probable PTSD was associated with early arrival at the WTC (HR, 1.38 vs. later arrival), an increasing number of aerodigestive symptoms (HR, 1.45/symptoms), and reporting an increase in alcohol intake since Sept. 11 (HR 3.43 vs. no alcohol intake).
"PTSD may thus persist or may arise not solely because of the intensity of the event experienced but also because of physical injuries or illnesses sustained during the event and changes in health behaviors after the event," the researchers concluded. "A full comprehensive treatment approach that addresses the physical, behavioral, and mental health consequences of WTC exposure is of critical importance."
The researchers acknowledged certain limitations of the study, including the fact that they used two different screening instruments to establish probable PTSD: one in years 1-4 after the attacks and one in years 6-9. "Although the agreement (as measured by the kappa statistic) was high, we cannot rule out the possibility that the two versions may have produced minor inconsistencies in probable PTSD prevalence," they wrote. "In addition, because feasibility concerns required a screening rather than a diagnostic instrument for PTSD, there may be some lack of correspondence between ‘probable’ and actual PTSD."
The study also lacked information on the treatment of PTSD, "which could have influenced recovery or delayed onset of symptoms."
The study was funded by the National Institute for Occupational Safety and Health.
The researchers stated that they had no relevant financial conflicts to disclose.