Particulate matter is associated with sputum culture conversion in patients with culture-positive tuberculosis

• Main Authors: Chen KY, Chuang KJ, Liu HC, Lee KY, Feng PH, Su CL, Lin CL, Lee CN, Chuang HC
• Format: Article
• Language: English
• Published: Dove Medical Press 2016-01-01
• Series: Therapeutics and Clinical Risk Management
• Subjects: air pollution; chest X-ray; particulate matter; sputum culture; tuberculosis.
• Online Access: https://www.dovepress.com/particulate-matter-is-associated-with-sputum-culture-conversion-in-pat-peer-reviewed-article-TCRM

Kuan-Yuan Chen,1,* Kai-Jen Chuang,2,3,* Hui-Chiao Liu,4,5 Kang-Yun Lee,1,6 Po-Hao Feng,1,6 Chien-Ling Su,1,4 Chii-Lan Lin,1,4 Chun-Nin Lee,1,4 Hsiao-Chi Chuang1,4 1Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, 2Department of Public Health, School of Medicine, College of Medicine, 3School of Public Health, College of Public Health and Nutrition, 4School of Respiratory Therapy, College of Medicine, Taipei Medical University, 5Division of Pulmonary Medicine, Department of Internal Medicine, Sijhih Cathay General Hospital, 6Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan *These authors contributed equally to the study Abstract: Emerging risk factors for tuberculosis (TB) infection, such as air pollution, play a significant role at both the individual and population levels. However, the association between air pollution and TB remains unclear. The objective of this study was to examine the association between outdoor air pollution and sputum culture conversion in TB patients. In the present study, 389 subjects were recruited from a hospital in Taiwan from 2010 to 2012: 144 controls with non-TB-related pulmonary diseases with negative sputum cultures and 245 culture-positive TB subjects. We observed that a 1 µg/m3 increase in particulate matter of ≤10 µm in aerodynamic diameter (PM10) resulted in 4% higher odds of TB (odds ratio =1.04, 95% confidence interval =1.01–1.08, P<0.05). The chest X-ray grading of TB subjects was correlated to 1 year levels of PM10 (R2=0.94, P<0.05). However, there were no associations of pulmonary cavitation or treatment success rate with PM10. In subjects with TB-positive cultures, annual exposure to ≥50 µg/m3 PM10 was associated with an increase in the time required for sputum culture conversion (hazard ratio =1.28, 95% confidence interval: 1.07–1.84, P<0.05). In conclusion, chronic exposure to ≥50 µg/m3 PM10 may prolong the sputum culture conversion of TB patients with sputum-positive cultures. Keywords: air pollution, chest X-ray, particulate matter, sputum culture, tuberculosis