Associations between air pollutants and acute exacerbation of drug-resistant tuberculosis: evidence from a prospective cohort study

Abstract

Background: Short-term exposure to air pollution may trigger symptoms of drug-resistant tuberculosis (DR-TB) through stimulating lung tissue, damaging tracheobronchial mucosa, the key anti-mycobacterium T cell immune function, and production and release of inflammatory cytokines.

Objective: To investigate the association between acute exacerbations of DR-TB and short-term residential exposure to air pollutants (PM₁₀, PM_2.5, SO₂, NO₂, CO and O₃) based on a large prospective cohort in Anhui Province, China.

Method: Patients were derived from a prospective cohort study of DR-TB in Anhui Province. All DR-TB patients underwent drug-susceptibility testing and prefecture-level reference laboratories confirmed their microbiologies. The case-crossover design was performed to evaluate the association between the risk of acute exacerbations of DR-TB and short-term residential exposure to air pollution.

Results: Short-term NO₂ exposure was significantly related to an elevated risk of first-time outpatient visit due to acute exacerbations of DR-TB(relative risk:1.159, 95% confidence interval:1.011 ~ 1.329). Stratification analyses revealed that the relationship between the risk of acute exacerbations and NO₂ exposure was stronger in the elderly (age ≥ 65) DR-TB patients, and in individuals with a history of TB treatment.

Conclusions: NO₂ Exposure was significantly associated with an elevated risk of acute exacerbation of DR-TB in Anhui Province, China.

Keywords: Air pollutants; Drug-resistant tuberculosis; NO2.