Faculty Bibliography

Rationale: Exposure to World Trade Center (WTC) dust and fumes is associated with onset of asthma-like respiratory symptoms in exposed community members including local workers, residents and clean-up workers. Although abnormal spirometry measurements are often not detected in these patients, impulse oscillometry (IOS) suggests abnormalities localized to the smaller airways. Peripheral C-reactive protein (CRP) is a marker of systemic inflammation. Since an association between CRP and asthma has been reported, we hypothesized that levels of CRP would be associated with lung function abnormalities as assessed by spirometry and IOS measurements in community members exposed to WTC dust/fumes and gasses. Methods: The WTC Environmental Health Center (EHC) is a treatment program for community members, with presumed WTC-related symptoms. Patients undergo a standardized evaluation including questionnaires and routine blood work, spirometry and IOS measurements. Between 10/1/2009 and 9/29/2011, a measurement of CRP was included for patients undergoing standardized visits. Measurements of lung function were compared utilizing the Wilcoxon test between subjects with normal vs. elevated CRP and further analyzed using linear regression models with log(CRP) as a continuous predictor. Regression analyses were adjusted for potential confounding factors including Body mass index (BMI), exposure category, and smoking history. Results: 208 WTC-exposed individuals met inclusion criteria. Valid spirometry and IOS data were available in 204 and 189 patients, respectively. Mean age was 49 years, 53% were female. Exposure categories (local workers, clean-up workers, residents) were associated with normal/elevated CRP levels (P=0.01). Smokers had a larger portion of elevated CRP (P=0.048). BMI was higher among the high CRP group (Wilcoxon test, P<0.001). FEV₁ and FVC were lower for the high CRP group (P=0.016, P=0.033). However, CRP level was not associated with the ratio FEV₁/FVC (P=0.58). The IOS measurements (R₅, R_5-20, AX ) were higher (P=0.01, P=0.003, P=.001, respectively) among the high CRP group. Multiple regression analysis confirmed that log(CRP) values were inversely correlated with % of predicted FEV 1 (P=0.009) and positively correlated with log(R₅) (P=0.02) and log(AX) (P=0.0045) after adjustment for log(BMI). Conclusions: Peripheral CRP was negatively correlated with levels of FEV₁ and positively correlated with IOS measurements in community members with WTC dust/gas/fume exposure. These data suggest a relationship between systemic inflammation, as reflected by CRP, and both large and small airway abnormalities in a WTC- exposed population

INTRODUCTION: We have previously shown improvement in spirometry parameters in symptomatic WTC dust exposed community members enrolled in the WTC Environmental Health Center treatment program. Additionally, impulse oscillometry (IOS) has demonstrated evidence for distal lung injury not apparent on spirometry. We hypothesize that longitudinal change of spirometry will differ based on presence or absence of distal airway injury and its response to bronchodilator at baseline. METHODS: 810 patients were identified with more than one spirometry and IOS assessment. IOS parameters included resistance at 5 and 20Hz (R₅ and R₂₀) and frequency dependence of resistance assessed as the difference between these parameters (R_5-20). Linear mixed effects modeling evaluated longitudinal changes in IOS parameters, FVC and FEV₁ for the entire population. Separate models were fit for subgroups categorized based on normal vs. abnormal baseline spirometry and normal vs. abnormal baseline IOS (R₅>3.96 cmH2O/L/s). Analyses were adjusted for confounding factors (age, gender, BMI, race/ethnicity, smoking, exposure category and dust cloud exposure). RESULTS: Mean age was 50yr. Patients were mostly female (52%) and had diverse race/ethnicity. At baseline, mean FVC was 91+/-17% predicted and FEV₁ was 88+/-18% predicted. A normal spirometry pattern was noted in the majority (67%; n=542). Despite normal spirometry, IOS revealed abnormalities in 67% (n=364). Longitudinal analysis of IOS parameters (R₅, R₂₀, R_5-20) over time revealed no significant trends for the entire population and for subgroups categorized by baseline spirometry pattern. In contrast, the longitudinal change in spirometry variables differed based on presence of IOS abnormality. In patients with normal spirometry, FEV₁ increased more rapidly in patients with abnormal baseline IOS compared to those with normal IOS (0.76 vs. 0.52 % predicted/yr; Table 1). For patients with abnormal baseline spirometry, FVC increased more rapidly in the abnormal vs. normal IOS patients (1.73 vs. 1.02 % predicted/yr). Patients with IOS response to bronchodilator (highest quartile for improvement of R₅ post bronchodilator) demonstrated a more rapid longitudinal increase in FEV₁ compared with patients without bronchodilator response (lowest quartile)(0.88 vs. 0.53 % predicted/yr,; Table 2). CONCLUSIONS: Spirometry parameters demonstrated improvement over time, while improvement in IOS parameters was not evident, suggesting potential irreversible injury in the distal lung. However, assessment of baseline distal airway function and its acute response to bronchodilator predicted longitudinal response of spirometry in patients enrolled in a treatment program. (Table Presented)

OBJECTIVE: : To describe pathologic findings in symptomatic World Trade Center-exposed local workers, residents, and cleanup workers enrolled in a treatment program. METHODS: : Twelve patients underwent surgical lung biopsy for suspected interstitial lung disease (group 1, n = 6) or abnormal pulmonary function tests (group 2, n = 6). High-resolution computed axial tomography and pathologic findings were coded. Scanning electron microscopy with energy-dispersive x-ray spectroscopy was performed. RESULTS: : High-resolution computed axial tomography showed reticular findings (group 1) or normal or airway-related findings (group 2). Pulmonary function tests were predominantly restrictive. Interstitial fibrosis, emphysematous change, and small airway abnormalities were seen. All cases had opaque and birefringent particles within macrophages, and examined particles contained silica, aluminum silicates, titanium dioxide, talc, and metals. CONCLUSIONS: : In symptomatic World Trade Center-exposed individuals, pathologic findings suggest a common exposure resulting in alveolar loss and a diverse response to injury

OBJECTIVE: To describe physical symptoms in those local residents, local workers, and cleanup workers who were enrolled in a treatment program and had reported symptoms and exposure to the dust, gas, and fumes released with the destruction of the World Trade Center (WTC) on September 11, 2001. METHODS: Symptomatic individuals underwent standardized evaluation and subsequent treatment. RESULTS: One thousand eight hundred ninety-eight individuals participated in the WTC Environmental Health Center between September 2005 and May 2008. Upper and lower respiratory symptoms that began after September 11, 2001 and persisted at the time of examination were common in each exposure population. Many (31%) had spirometry measurements below the lower limit of normal. CONCLUSIONS: Residents and local workers as well as those with work-associated exposure to WTC dust have new and persistent respiratory symptoms with lung function abnormalities 5 or more years after the WTC destruction