Context: The World Trade Center Health Registry provides a unique opportunity to examine long-term health effects of a large-scale disaster.
Objective: To examine risk factors for new asthma diagnoses and event-related posttraumatic stress (PTS) symptoms among exposed adults 5 to 6 years following exposure to the September 11, 2001, World Trade Center (WTC) terrorist attack.
Design, setting, and participants: Longitudinal cohort study with wave 1 (W1) enrollment of 71,437 adults in 2003-2004, including rescue/recovery worker, lower Manhattan resident, lower Manhattan office worker, and passersby eligibility groups; 46,322 adults (68%) completed the wave 2 (W2) survey in 2006-2007.
Main outcome measures: Self-reported diagnosed asthma following September 11; event-related current PTS symptoms indicative of probable posttraumatic stress disorder (PTSD), assessed using the PTSD Checklist (cutoff score > or = 44).
Results: Of W2 participants with no stated asthma history, 10.2% (95% confidence interval [CI], 9.9%-10.5%) reported new asthma diagnoses postevent. Intense dust cloud exposure on September 11 was a major contributor to new asthma diagnoses for all eligibility groups: for example, 19.1% vs 9.6% in those without exposure among rescue/recovery workers (adjusted odds ratio, 1.5 [95% CI, 1.4-1.7]). Asthma risk was highest among rescue/recovery workers on the WTC pile on September 11 (20.5% [95% CI, 19.0%-22.0%]). Persistent risks included working longer at the WTC site, not evacuating homes, and experiencing a heavy layer of dust in home or office. Of participants with no PTSD history, 23.8% (95% CI, 23.4%-24.2%) reported PTS symptoms at either W1 (14.3%) or W2 (19.1%). Nearly 10% (9.6% [95% CI, 9.3%-9.8%]) had PTS symptoms at both surveys, 4.7% (95% CI, 4.5%-4.9%) had PTS symptoms at W1 only, and 9.5% (95% CI, 9.3%-9.8%) had PTS symptoms at W2 only. At W2, passersby had the highest rate of PTS symptoms (23.2% [95% CI, 21.4%-25.0%]). Event-related loss of spouse or job was associated with PTS symptoms at W2.
Conclusion: Acute and prolonged exposures were both associated with a large burden of asthma and PTS symptoms 5 to 6 years after the September 11 WTC attack.