Development of breath test for pneumoconiosis: a case-control study

Hsiao-Yu Yang,Ruei-Hao Shie,Pau-Chung Chen,Che-Jui Chang

doi:10.1186/s12931-017-0661-3

Abstract

BackgroundLipid peroxidation plays an important role in the pathogenesis of pneumoconiosis. Volatile organic compounds (VOCs) generated from lipid peroxidation might be used to detect pneumoconiosis. The objective of this study was to develop a breath test for pneumoconiosis.MethodsA case-control study was designed. Breath and ambient air were analysed by gas chromatography/mass spectrometry. After blank correction to prevent contamination from ambient air, we used canonical discriminant analysis (CDA) to assess the discrimination accuracy and principal component analysis (PCA) to generate a prediction score. The prediction accuracy was calculated and validated using the International Classification of Radiographs of the Pneumoconiosis criteria combined with an abnormal pulmonary function test as a reference standard. We generated a receiver operator characteristic (ROC) curve and calculated the area under the ROC curve (AUC) to estimate the screening accuracy of the breath test.ResultsWe enrolled 200 stone workers. After excluding 5 subjects with asthma and 16 subjects who took steroids or nonsteroidal anti-inflammatory drugs, a total of 179 subjects were used in the final analyses, which included 25 cases and 154 controls. By CDA, 88.8% of subjects were correctly discriminated by their exposure status and the presence of pneumoconiosis. After excluding the VOCs of automobile exhaust and cigarette smoking, pentane and C5-C7 methylated alkanes constituted the major VOCs in the breath of persons with pneumoconiosis. Using the prediction score generated from PCA, the ROC-AUC was 0.88 (95% CI = 0.80—0.95), and the mean ROC-AUC of 5-fold cross-validation was 0.90. The breath test had good accuracy for pneumoconiosis diagnosis.ConclusionThe analysis of breath VOCs has potential in the screening of pneumoconiosis for its non-invasiveness and high accuracy. We suggest that a multi-centre study is warranted and that all procedures must be standardized before clinical application.

Highlights

IntroductionLipid peroxidation plays an important role in the pathogenesis of pneumoconiosis
After excluding five subjects with a medical history of asthma with fractional exhaled nitric oxide (FeNO) greater than 50 ppb on the examination day and 16 subjects using steroids or taking nonsteroidal anti-inflammatory drugs (NSAIDs) on the examination day, a total of 179 subjects were included in the final analysis, which included 25 cases and 154 controls
Lipid peroxidation plays an important role in the pathogenesis of pneumoconiosis

Summary

Introduction

Lipid peroxidation plays an important role in the pathogenesis of pneumoconiosis. Pneumoconiosis is an important occupational lung disease that primarily consists of silicosis and asbestosis. Silicosis results from inhaling silica, which is a common component of rock and sand. Ceramic workers, quarry workers, miners, tunnel drillers, sand blasting workers, sand casting workers, and construction or demolition workers are at high risk for inhaling silica at work [1]. Asbestosis results from inhaling asbestos fibres that cause diffuse interstitial pulmonary fibrosis. The high-risk population includes shipyard workers, construction workers, asbestos textile workers, manufacturing brake lining workers, and asbestos miners or millers [1]. Asbestos has been gradually banned in many countries, mortality due to asbestos exposure continues to increase in many developed countries. The development of new diagnostic methods for pneumoconiosis is warranted

Objectives

Methods

Results

Discussion

Conclusion