Asthma and PTSD Symptoms Persist 5-6 Years After Exposure to World Trade Center Attacks

A study published in the August 5th, 2009 issue of The Journal of the American Medical Association reported that acute and prolonged exposures to the World Trade Center (WTC) terrorist attacks were associated with a large burden of asthma and posttraumatic stress (PTS) symptoms 5 to 6 years after the attacks.

Robert M. Brackbill, PhD, MPH, of the Centers for Disease Control and Prevention, Atlanta, and colleagues of the New York City Department of Health and Mental Hygiene, and Columbia University, New York, examined the risk factors for new asthma diagnoses and event-related posttraumatic stress (PTS) symptoms among adults who were exposed to the September 11th attacks.

The longitudinal cohort study utilized data from the World Trade Center Health Registry, the largest post-disaster exposure registry in U.S. history. The Registry allows health professionals to track and investigate illness and recovery related to the WTC disaster and periodically follow-up with enrollees over a 20-year period to track changes in physical and mental health.

Wave 1 (W1) of the study enrolled of 71,437 adults in 2003-2004, including rescue/recovery workers, lower Manhattan residents, lower Manhattan office workers, and passersby eligibility groups; 46,322 adults from the W1 enrollment (68%) completed the follow-up wave 2 (W2) survey in 2006-2007.

The surveys included questions regarding symptoms of asthma following September 11 and event-related PTS symptoms indicative of probable PTSD, assessed using the PTSD Checklist (a self-report symptoms rating scale).

Of W2 participants with no stated asthma history, 10.2% reported new asthma diagnoses post-event. 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. Asthma risk was highest among rescue/recovery workers on the WTC pile on September 11 (20.5%). 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% reported PTS symptoms at either W1 (14.3%) or W2 (19.1%). Nearly 10% had PTS symptoms at both surveys, 4.7% had PTS symptoms at W1 only, and 9.5% had PTS symptoms at W2 only. At W2, passersby had the highest rate of PTS symptoms (23.2%). Event-related loss of spouse or job was associated with PTS symptoms at W2.

The researchers add that applying reported outcome rates from the follow-up survey results to the approximately 409,000 potentially exposed persons, roughly 25,500 adults are estimated to have experienced post-event asthma and 61,000 are estimated to have experienced symptoms indicative of probable PTSD.

"Our findings confirm that, after a terrorist attack, mental health conditions can persist if not identified and adequately treated and that a substantial number of exposed persons may develop late-onset symptoms. Our study highlights the need for surveillance, outreach, treatment, and evaluation of efforts for many years following a disaster to prevent and mitigate health consequences," the authors conclude.