Risk factors for persistence of lower respiratory symptoms among community members exposed to the 2001 World Trade Center terrorist attacks

Abstract

ObjectivesWe studied the course of lower respiratory symptoms (LRS; cough, wheeze or dyspnoea) among community members exposed to the 9/11/2001 World Trade Center (WTC) attacks during a period of 12–13 years following the attacks, and evaluated risk factors for LRS persistence, including peripheral airway dysfunction and post-traumatic stress disorder (PTSD).MethodsNon-smoking adult participants in a case-control study of post-9/11-onset LRS (exam 1, 2008–2010) were recruited for follow-up (exam 2, 2013–2014). Peripheral airway function was assessed with impulse oscillometry measures of R5 and R5-20. Probable PTSD was a PTSD checklist score ≥44 on a 2006–2007 questionnaire.ResultsOf 785 exam 1 participants, 545 (69%) completed exam 2. Most (321, 59%) were asymptomatic at all assessments. Among 192 participants with initial LRS, symptoms resolved for 110 (57%) by exam 2, 55 (29%) had persistent LRS and 27 (14%) had other patterns. The proportion with normal spirometry increased from 65% at exam 1 to 85% at exam 2 in the persistent LRS group (p<0.01) and was stable among asymptomatic participants and those with resolved LRS. By exam 2, spirometry results did not differ across symptom groups; however, R5 and R5-20 abnormalities were more common among participants with persistent LRS (56% and 46%, respectively) than among participants with resolved LRS (30%, p<0.01; 27%, p=0.03) or asymptomatic participants (20%, p<0.001; 8.2%, p<0.001). PTSD, R5 at exam 1, and R5-20 at exam 1 were each independently associated with persistent LRS.ConclusionsPeripheral airway dysfunction and PTSD may contribute to LRS persistence. Assessment of peripheral airway function detected pulmonary damage not evident on spirometry. Mental and physical healthcare for survivors of complex environmental disasters should be coordinated carefully.

Technical standards for respiratory oscillometry

“…The short testing times and ease of administration for subjects are potential advantages in this setting. Oscillometry can be more sensitive than spirometry for detection of airways disease due to occupational exposure [48][49][50][51][52][53][54][55], but this area requires further research.…”

Characterization of Persistent Uncontrolled Asthma Symptoms in Community Members Exposed to World Trade Center Dust and Fumes

“…We defined our study population to include those with normal spirometry values. We and others have previously reported the association of small airway dysfunction with symptoms and exposures in many WTC-exposed community members with preserved spirometry [ 16 , 35 , 43 , 44 , 67 ] and we therefore hypothesized that persistent respiratory symptoms would be associated with increased small airway dysfunction in this study. The median values for all measures of forced oscillation, including those considered to assess small airway function (R5–20), were slightly elevated (abnormal) in the group as a whole.…”

“…These guidelines included step-up therapy with inhaled corticosteroids (ICS) and eventual addition of long acting bronchodilators (LABAs) to gain control of symptoms. Despite this standardized approach, many patients with WTC exposures continued to report persistent uncontrolled LRS [ 14 , 15 , 16 , 17 ]. Many had spirometry values that were within normal limits despite their continued symptoms.…”

World Trade Center Health Program: First Decade of Research

“…Although they were resolved over time in many exposed residents, symptoms persisted in significant numbers [ 16 , 26 ]. Reasons for response heterogeneity remain elusive, although a recent study of survivors suggested that peripheral airway dysfunction and PTSD may contribute to the persistence of lower respiratory symptoms [ 27 ].…”