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

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, PM2.5, 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.

Determining Mycobacterium tuberculosis Drug Resistance and Risk Factors for Multidrug-Resistant Tuberculosis in Sputum Smear-Positive Tuberculosis Outpatients in Anhui Province, China, 2015-2016.

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB) is currently a major problem in China. The prevention and treatment work for MDR-TB patients started late in Anhui province. To determine the prevalence of MDR-TB in sputum smear-positive TB patients (SSPTBPs) and analyze the risk factors for MDR-TB in Anhui province, we conducted an investigation of drug resistance among SSPTB outpatients from September 2015 to August 2016. METHODS: A stratified cluster-randomized sampling method was used to obtain a representative sample. It was estimated that 2290 new cases and 440 previously treated cases of SSPTBPs needed to be recruited from 40 survey sites. Isolates were tested for resistance to six first-line and second-line anti-TB drugs. Information from patient questionnaire survey was used to identify factors linked to MDR-TB. RESULTS: Finally, a total of 3047 SSPTBPs were recruited from 40 survey sites; of these, 2530 specimens were successfully cultured and had drug susceptibility testing done. The proportions of rifampin resistant (RR)-TB were 11.42% (289/2530, 95% CI: 10.18-12.66%), 7.64% (163/2133, 95% CI: 6.38-8.62%) and 31.74% (126/397, 95% CI: 27.38-36.60%) in all cases, new cases and previously treated cases, respectively, and the proportions of confirmed MDR-TB were 7.63% (193/2530, 95% CI: 6.59-8.66%), 4.97% (106/2133, 95% CI: 4.05-5.89%) and 21.91% (87/397, 95% CI: 17.83-26.00%), respectively. The ofloxacin resistance rate in previously treated SSPTBPs reached 21.66% (95% CI: 17.33-26.75%). Patients who had received two or more anti-TB treatment courses were significantly associated with MDR-TB compared to patients who have received one anti-TB course. CONCLUSION: MDR-TB prevalence was high among SSPTBPs in Anhui province, and past anti-TB treatment course was associated with MDR-TB.

Epidemiological characteristics of pulmonary tuberculosis in Anhui Province, Eastern China from 2013 to 2018.

OBJECTIVE: Pulmonary tuberculosis (TB) is a severe infectious respiratory disease, the burden of which remains high in China. To provide scientific evidence for developing more targeted prevention and control strategies, this study aimed to determine the incidence trends and explore the epidemiological characteristics of pulmonary TB in Anhui Province, Eastern China between 2013 and 2018. METHODS: The retrospective study analyzed information regarding pulmonary TB cases reported by the National Infectious Disease Reporting System and census data collected from the Anhui Provincial Bureau of Statistics. RESULTS: Overall, 211,892 cases of TB patients were reported in Anhui Province, China between 2013 and 2018, with an average annual reported incidence rate of 57.7 per 100,000 persons. A significant decrease in the incidence rate of pulmonary TB (p < 0.001) was observed during the study period. Men had a higher incidence rate of pulmonary TB than women (p < 0.001). The highest annual average reported incidence rate was 204.2 per 100,000 persons in those aged 70-74 years. The number of farmers with pulmonary TB, i.e., 155,415, accounted for 73.4% of all cases. Moreover, the peak period of reported cases was from January to March. Four cities along the Yangtze River-Anqing, Tongling, Chizhou, and Wuhu-reported significantly higher incidence rates of pulmonary TB than other cities (p < 0.001). CONCLUSIONS: From 2013 to 2018, there was a significant decline in the incidence rate of pulmonary TB in Anhui Province, with peaks occurring from January to March. Prevention and control strategies targeting men, people aged 70-74 years, farmers, and the four cities along the Yangtze River should be strengthened.