Case–Control Study of Lung Function in World Trade Center Health Registry Area Residents and Workers

Abstract

This study links persistent respiratory symptoms and oscillometric abnormalities in World Trade Center-exposed residents and area workers. Elevated R₅ and R₅₋₂₀ in cases despite normal spirometry suggested distal airway dysfunction as a mechanism for symptoms.

Metabolic Syndrome Biomarkers Predict Lung Function Impairment

“…Obesity is the strongest predictor of abnormal pulmonary function (18,33). The findings are consistent with other WTC-exposed cohorts in that symptomatic cases had higher BMI than asymptomatic control subjects (34). Individual MetSyn components were stronger predictors of lung disease than the aggregate case definition.…”

Lessons From the World Trade Center Disaster

“…Conservative upper limits of normal (ULN) were selected that approximate 150% of mean data in normal subjects. 9,15,[25][26][27][28] Data obtained in our laboratory in 80 asymptomatic nonsmoking subjects with normal spirometry and without lung disease fell within these limits.…”

“…The abnormality resembled a restrictive defect, with reduced VC, FRC, and TLC and preservation of FEV 1 /VC, but parenchymal, chest wall, or The predominant spirometric abnormality following WTC dust exposure was reduced VC with normal FEV 1 /VC. [6][7][8][9][10] Studies postulated primary airway rather than parenchymal disease based on normal chest radiographs and either bronchial hyperreactivity and/or airway wall thickening and AT on CT scan examination. 7,10,12,13,29 The fall in VC in fi refi ghters from before to after September 11, 2001, correlated with degree of AT assessed by plethysmography, 12 and reduced VC and TLC was associated with AT on CT scan in other fi rst responders.…”

“…22 Resistance and reactance were calculated from airfl ow and pressure oscillations between frequencies of 5 to 35 Hz. Parameters included the following: (1) resistance at oscillation frequencies of 20 Hz (R 20 ) and 5 Hz (R 5 ), (2) fre quency dependence of resistance calculated as change in resistance between 5 and 20 Hz (R [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] ), (3) resonant frequency (Fres), and (4) reactance area (AX). Trials with stable tidal and end-expiratory volume were analyzed.…”

“…[6][7][8][9][10] Although TLC has not been consistently reported, chest radiographs have generally been normal, and parenchymal disease is not evident in the majority of subjects. Airway disease was demonstrated by bronchial hyperreactivity or presence of bronchial wall thickening and/or air trapping (AT) on CT scan.…”