Objective: We described the patterns of asthma hospitalization among persons exposed to the 2001 World Trade Center (WTC) attacks, and assessed whether 9/11-related exposures or comorbidities, including posttraumatic stress disorder (PTSD) and gastroesophageal reflux symptoms (GERS), were associated with an increased rate of hospitalization.
Methods: Data for adult enrollees in the WTC Health Registry, a prospective cohort study, with self-reported physician-diagnosed asthma who resided in New York State on 9/11 were linked to administrative hospitalization data to identify asthma hospitalizations during September 11, 2001-December 31, 2010. Multivariable zero-inflated Poisson regression was used to examine associations among 9/11 exposures, comorbid conditions, and asthma hospitalizations.
Results: Of 11 471 enrollees with asthma, 406 (3.5%) had ≥1 asthma hospitalization during the study period (721 total hospitalizations). Among enrollees diagnosed before 9/11 (n = 6319), those with PTSD or GERS had over twice the rate of hospitalization (adjusted rate ratio (ARR) = 2.5, 95% CI = 1.4-4.1; ARR = 2.1, 95% CI = 1.3-3.2, respectively) compared to those without. This association was not statistically significant in enrollees diagnosed after 9/11. Compared to higher educational attainment, completing less than college was associated with an increased hospitalization rate among participants with both pre-9/11- and post-9/11-onset asthma (ARR = 1.9, 95% CI = 1.2-2.9; ARR = 2.6, 95% CI = 1.6-4.1, respectively). Sinus symptoms, exposure to the dust cloud, and having been a WTC responder were not associated with asthma hospitalization.
Conclusions: Among enrollees with pre-9/11 asthma, comorbid PTSD and GERS were associated with an increase in asthma hospitalizations. Management of these comorbidities may be an important factor in preventing hospitalization.
Keywords: Asthma hospitalization; World Trade Center; cohort study; comorbidity; gastroesophageal reflux; posttraumatic stress disorder.