Air pollution and tuberculosis

A cross-sectional study of 1,073 patients aged 19 to 90 years, recruited from the chest department clinic of a TB center in Taipei, Taiwan, was conducted from April 2014 to November 2022. Most participants were male (59.9%), with an average age of 64.7 years and a mean BMI of 21.45 kg/m². Alcohol consumption was reported by 10.4% of participants, while smoking status included 13.2% current smokers, 20.0% ex-smokers, and 66.7% non-smokers. The average annual family income was $30,493 USD. Daily mean ambient PM2.5 levels over 1, 7, and 30 days ranged from 16.81 to 17.15 µg/m³.[1] See also: Lin TB Lab Taiwan

Patients with pulmonary nontuberculous mycobacteria (NTM) displayed distinct characteristics compared to other groups, including higher age, a lower proportion of males, shorter height, lower smoking rates, reduced income, and fewer chest X-ray (CXR) abnormalities. Pulmonary NTM patients were exposed to lower PM2.5 levels over 1- and 7-day periods in both regional and lobar lung deposits, while pulmonary multidrug-resistant TB (MDR-TB) patients were exposed to lower PM2.5 levels over 30 days.[1]

A 1 µg/m³ increase in ambient PM2.5 was linked to a higher risk of pulmonary MDR-TB infections and increased lung abnormalities, particularly in the upper and middle lobes. PM2.5 deposition over 1-, 7-, and 30-day periods showed significant exposure-response relationships with radiographic severity in TB, MDR-TB, and NTM patients. While PM2.5 exposure reduced nodules and cavities in some regions, it increased abnormalities in others. Overall, higher PM2.5 levels were strongly associated with worsened lung conditions and greater TB infection risks.[1]

A systematic review and meta-analysis found that the association between household use of solid fuels and tuberculosis (TB) is supported by very low levels of evidence. Burning solid fuels can pose serious health risks, particularly when stoves are inefficient, and ventilation is poor. These conditions contribute to acute lower respiratory infections in children under five, chronic obstructive pulmonary disease (COPD), and lung cancer. Pollutant concentrations from burning solid fuels vary depending on the stove type, burning location, and ventilation quality. These factors play a critical role in quantifying pollutant levels.[2]

Respirable risk factors, such as active and passive smoking and indoor air pollution from biomass, may impair airway defense mechanisms, increasing the risk of tuberculosis (TB). High levels of ambient air pollution in developing countries are associated with persistently high TB rates, highlighting the need for further research into its impact on global TB control. Fine particles and traffic-related pollutants, including nitrogen dioxide, nitrogen oxides, and carbon monoxide, have been linked to an increased risk of active TB. Laboratory and ecological studies indicate a positive association between ambient air pollution and TB incidence. However, the true relationship may be underestimated due to potential residual confounding by area-level socioeconomic factors.[3]

Tobacco smoking and indoor air pollution from solid fuel use are key risk factors for COPD, lung cancer, and tuberculosis (TB), particularly in developing countries. Reducing these risks through measures like tobacco taxation, cleaner fuel adoption, and targeted programs could significantly lower disease mortality and TB incidence. These diseases disproportionately affect low-income communities, imposing economic burdens through healthcare costs and reduced productivity. Revenue from tobacco taxes could fund TB treatment programs, clean energy initiatives, and nutritional support, improving health outcomes in marginalized populations.[4]

References:

1. Makrufardi, F., Chuang, H.C., Suk, C.W., Lin, Y.C., Rusmawatiningtyas, D., Murni, I.K., Arguni, E., Chung, K.F. and Bai, K.J., 2024. Particulate matter deposition and its impact on tuberculosis severity: A cross-sectional study in Taipei. Science of the Total Environment, 924, p.171534.

2. Lin, H.H., Suk, C.W., Lo, H.L., Huang, R.Y., Enarson, D.A. and Chiang, C.Y., 2014. Indoor air pollution from solid fuel and tuberculosis: a systematic review and meta-analysis. The International journal of tuberculosis and lung disease, 18(5), pp.613-621.

3. Lai, T.C., Chiang, C.Y., Wu, C.F., Yang, S.L., Liu, D.P., Chan, C.C. and Lin, H.H., 2016. Ambient air pollution and risk of tuberculosis: a cohort study. Occupational and environmental medicine, 73(1), pp.56-61.

4. Lin, H.H., Murray, M., Cohen, T., Colijn, C. and Ezzati, M., 2008. Effects of smoking and solid-fuel use on COPD, lung cancer, and tuberculosis in China: a time-based, multiple risk factor, modelling study. The Lancet, 372(9648), pp.1473-1483.